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TRACE® 700

1. 6 176 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN Printing used library members Combining files 1 If a project file is open click Close on the File menu 2 Click New and then New File Based On on the File menu 3 Enter a name for the NEW combined file and click Open VERY IMPORTANT If an existing file name Is selected THE FILE WILL BE ERASED 4 Select the existing projects to be merged Highlight the first file to be merged and then hold down the Ctrl key while clicking on the other file s to be merged CDS PRMOO0O1 EN TRACE 700 User s Manual When working on large projects it is often useful to divide the model into separate files and then combine the individual projects into one merged file The New File Based On feature allows this to be done Note It is VERY IMPORTANT to back up data before attempting the merge process TRACES TOO for esoclusive use bey ky Miura Lirama Hie Pee orien Oper Oleh 2 TRACER TO Lari irii TRAE M alien Hi Arrie iri Sum Exhling kandis Hajr Fi eitir ri Iipat F Tuahoraed Sathirsys LEW tora care EO re PEDA E e A Erirgy Tutcri ety e tut asi LockinfoaPoects dege T enpad L Ewein te CF LEren z Trice F Complesed Tarorinak ara jema ro E Tinoriats u EF Ceiplased Tassrialihak T F Tec oe ve 2 Tuteriaeres T Enege Tutorial ee SP TRAC EOD
2. cc ceececeececeeeeeeeeeeeeeeeeeeeans 3 59 Domestic hot water assigned to a boller 00005 3 62 Alrto air heat OUMP SYSTEM cccceecceccee sees eeee esse seen 3 64 Watersource heat OUMP SYSTEM cceecceeeeee cece nena 3 68 Ground source heat pUMp SYSTEM ccccceeeeseeeeeeeeeees 3 72 Central geothermal Chillers cece ccccecceeeceeeeeenan eens 3 76 Variable refrigerant flow SYSTEM ccccecccseeceeeeeeeeeeen es 3 81 Chapter4 System Design Options Desiccant dehumidification sick cee cna eee 4 2 Coil loop for exhaust air energy recovery ccceeeeeee eee 4 8 Total energy enthalpy Wheel cccccececceeeeseeeen eens 4 15 Fixed plate heat ExChanQel ccccceccceceeneeeeeeeeeeneeens 4 21 FICE PIDE sorat aa A E n e eatin 4 27 SEM DIEWE iea a e T n 4 34 Direct and indirect evaporative COOIING cccccceeeeeee 4 40 Dedicated outdoor air SYSTEMS ss eiiesisreerrrrerrere 4 45 iv Contents TRACE 700 User s Manual e CDS PRM001 EN Dual Path Air Handler Split Dehumidification Unit 4 67 systems with 100 outdoor alf 4 73 COLAO SEO UO eieae ea a eA 4 76 Chilled Dea S esusen a a a a 4 79 Underilogr adis tribUUO Mesero aryna 4 84 Displacement ventilatie eunan aea teens 4 88 ASHIRAE Standard 62 1 xiscics 2805 Svea naaa aa 4 91 Chapter5 System Control Strategies FIPSIG ES SCOMOMUIZENS eae a 5 2 Pall CYCO nee ea puraahautshuyianteiab
3. For Help press F1 Completing the analysis After calculating the baseline alternative the proposed and baseline results should be compared The LEED Energy Performance Summary Report provides results in a format similar to the EAp2 and EAc1 templates for both version 2 2 and version 3 If the baseline energy cost is less than the proposed further analysis is required Consider these three basic steps when determining potential causes m identify areas where the baseline consumes more energy e g space heating space cooling fans m Verity inputs for these areas e g crosscheck ASHRAE 90 1 2007 requirements m Verify proposed design inputs e g schedules envelope If the baseline alternative energy cost is greater verify the unmet hours for both alternatives comply with the ASHRAE 90 1 2007 requirement If the unmet hours do not comply with the requirement review the following for methods of reducing or eliminating them Unmet hours Unmet load hours are triggered in TRACE when space conditions are outside the thermostat setpoints Unmet hours occur for a wide variety of reasons They are restricted to hours when the excess load on a coil is at least 1 percent greater than the design coil capacity and at least one room attached to that coil is in excess of 1 5 F of the thermostat setpoint for that hour CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 101 Modeling for LEED
4. Tver Fan Dodie Duci VAV UFAD VAV w Ratebosd Heater Underfloor Air Distribution SFPVAY Unt Heaters Unt Vertiaice Vanable Retageiart Voke Venable enopecaise Cornlart Voire 2 On the Dedicated OA System dercrotion VAM and DOAU Veisbk Vome Plehest 300 Min Flow Delak tab select the type of i 2 Coniiguration Dehu nony or Cod Hem Cardiol method Frond Selpr dedicated ventilation unit Cocirea Hawting Design Setporti Cooling Heating Segan Listi to be modeled In this Cooling neck order tub F Supply ai dy bulb high imi example the dedicated i 5 dy Supiy am chy bad oer he ventilation unit will supply Conlin SA dew point kow init F low dew point air not reheated in cooling a ei P bea Ceeabrnag cso evelsble 100 Deed Petar uiden Dueck mode and air at a specific Hewirgend favor Se evel Stee z dry bulb in heating mode Opona py retene O Therefore Dehumidify 2 priority or Cool Heat Sectors _ Dedicated A None no dedicated ventilation unit Cool heat a dedicated ventilation unit is used to cool the outdoor air to the userinput cooling dry bulb during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season Dehumidify priority or Cool Heat a dedicated ventilation unit is used to dehumidify the outdoor air to the userinput cooling dew point not reheated during the cooling season or heat the outdo
5. Abemanve 1 Room description Hores AIN Templster Ficom Exen gt federal Eternal 100 Percert Outdoor Ar fio Og Aatiow 2 100 fy Hig Airflow Available 100 Note Ventilation can also be input at the system level On the Options tab of Create Systems click Advanced Options to override system level ventilation Refer to online Help for additional information related to system level ventilation input and how it will affect the simulation duei am barri from iiir oom dacon Hota Fil H cima aisean a tans gt Cancel oniri E na Orange a ledge al Werden Apply ASHRAE Side aa Ha CE ee 100 Parcent Quedsot Aur Cooling to EE Chg Aafk Hesira ro EE Hig Aiie Schedule Avadsble 100 1 Plate hh br hares he 4 T Sethvedule vasa 100 Tlate Scheie Jaw nisde WOES Tyee Default ba Antlowe TRACE 700 User s Manual e CDS PRMOO1 EN Systems with 100 outdoor air 5 Select the appropriate airside system associated fans static pressures and supply air temperature ranges for the system in Create Systems 6 Assign the rooms to the airside system and calculate the design results for the air handler CDS PRMOO01 EN TRACE 700 User s Manual Abemotve 1 Sythem description fHu 1 Vatable Voume Reheat 30 Min Flow Delak Fan cycling schedule No tan eyeing FC Certrfugal const vol 0 00032 kw Citrrin wg Ts N A kW h FC Cert
6. cooling coil Selector a a coe Pad TRACE 700 User s Manual e CDS PRMOO1 EN 4 Select the exhaust side deck for the device In this case the energy from the system exhaust air stream will be used to reheat the ventilation air As a result System Exhaust will be selected Note If the proper airstreams are not selected for supply side and exhaust side decks of the energy recovery transfer device then the unit will not function correctly or may not function at all The Airflows section of the System Checksums report can be used to verify that a specific airflow is available for energy recovery On the System Checksums reports Room Exhaust Rm Exh System Exhaust Exhaust and Return air Return Air 5 Choose the schedule that describes when the sensible energy wheel is permitted to operate The schedule Available 100 will allow the device to operate yearround CDS PRMOO01 EN TRACE 700 User s Manual IP Create Systems Options alax Abemative System devcrtion w SHP wah DOAS WeerSouel Note If two energy pe shen Fore recovery transfer devices baal ang ia Desist ooo ao ree Are Input and both stage 1 Dect cad schedule Arae 100021 Mw cuseeor and Stage 2 devices are i a P ERAR 4 given the same exhaust side miec cod pohode Avale 10 7 deck then stage 1 will be Siege ZADA priate tri ire fetes upstream of stage 2 oOo emre IE COSTS a Scheele avai 0
7. 2 To create the second alternative click Copy Alternative on the Alternatives Setup menu OEE to create a CO of Adora View Optra Litearies Tempides Aernalives Setup Widow Help 7 py Seo SR ook atest STAR Alternative 1 3 With the second alternative ree Prs x created the templates Note Templates con be ured to make changes to rooms E anf Ep pbe from Alternative 1 must be moa io te donaire copied so that the design aed i and system section of I zj Create templates for this akemative bared on Alternative 2 will be cma famme 3 al recalculated with gr C Edt comments daylighting Right click Alternative 2 and click Templates on the list To make the copy of the templates editable select Create Templates for this Alternative based on Alternative 1 and click OK 067 1172003 9 254M 0671172003 09 254M CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 35 Daylighting 5 36 4 lo activate Daylighting click Create Daylighting Definition on the Actions menu The Daylighting Parameters screen should open displaying where the daylighting definitions will be created and added to the spaces The Daylighting Parameters screen should open to the General tab Daylighting System Control Strategies Da germanen eo SH ke S T amp T TRANE qr Miama o Daking ok Oregon E ises mois rv Use kenative 1 Rated Leary Vhs rons Use Alemairee 1 J
8. 6 Select a destination coin E ago directory for exporting the ae file name the file and Ti oe click Save amine 7 Repeat the same process for the My Computer Alternative 2 input data cs f meor E MEE Sie ost Poch Ten Fom enn cancel alternative _1 rtf Microsoft Word lax fle Edt View Insert Foma Toos Table Window Help Adobe POF 4 nome Avot amp EERE ip eset change IS Oe Ae SOFA SAL soto 8 hn Ot t gt a B Al a Fe svolPDesktopialtarrsatig_ 1 rit a 8 Open the file for Alternative 1 in MS Word click Track Changes on the Tools menu and click Compare Documents ae Se Se Se ee ee Se Se Se See Se Se Se Se ee T ee ee ee ee ENTERED VALUES ROOM BY ROOM By Trane Note The location and actual name of Track GENERAL INFORMATION Create Rooms Rooms PEOPLE AND LIGHTS Creati fume Fico area 12i a Denan aoina Of w F eop Acthity General Ottce Space Sala gt to Com tB Ao Changes may vary FE oe ig le oor a to a QX Ci Th Look in depending on your version nem cade Upham ans ce Foture Type RECTLY of MS Word la E aN Olann F acter 10 9 Select the Files of Type j as Rich Text Format or MS Word whichever was selected in step 4 select the export file containing Alternative 2 data and click Open f i 49 um Pesto fxn tetromacnn Q 4 caw Ble Edt Yew peet Format Jass Tabe windoer pep Adote PDE
9. Room 1 East facing E Cooling space Qs 11 000 Btu Maximum sensible load calculated by TRACE 700 based on heat gains at the time of the space peak 9 a m for this example E Cooling coil Qs 5 000 Btu Sensible load calculated by TRACE 700 based on heat gains at the time of the system cooling coil peak 3 p m for this example CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 57 Oversizing and undersizing E Cooling Ts 55 F Input by the user or calculated by TRACE 700 E VAV minimum stop 50 percent of cooling supply airflow entered on Airflows tab of Create Rooms The cooling supply cfm would be calculated using the sensible heat equation and the loads at the time of the space peak 9 a m for this east facing office The minimum supply cfm would be calculated using the cooling supply cfm and the minimum stop Cooling 11 000 1 1x SAx 75 55 SA 500 cfm Minimum airflow supplied to space SA 500 x 50 SA 250 cfm When sizing the cooling coil oversizing would appear in this example based on the minimum airflow requirements over undersizing 1 1 x 250 x 75 55 5 000 500 Btu This would indicate overcooling of 500 Btu because the space would need only 227 cfm but the minimum stop on the VAV box is 250 cfm Any time the minimum airflow is more than what is required to condition the space oversizing of the coil should be expected Scenario 7
10. Selection Oram Dedicated 1A TerpHumiy W Create Systems Dedicated Ventilation Abemative sytem devciotn Fanos DOD Ren Configuation Esa Hea O Ceed Food Seles Cooling Hasting Design Setpoint Cooling blewing Seapine Limiti Coging rupp ea dep bulb ro F Supply ai dy bub high m F Hemno cpp ar dybub ED T Supply an dey bulbs kerb Coulngnepyarderpon Cooling SA dew pairt hihira F Cevelreg SA cw poart kow iit Dedicated Verily Schedules Cenk ated Viemtilion Loggiord Fiom Dieet Canina cod Avedsble 100 Deck 7 anced Syne Creal fete System The dedicated ventilation unit will be placed at the system level It will pretreat the outdoor air for all of the rooms and zones assigned to the airside system This is the most common choice for dedicated ventilation systems The System Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Zone Each zone or room assigned directly to the system will get a separate dedicated ventilation system The Zone Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Room Each room will get a separate dedicated ventilation system The Room Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Same level as main cooling coil The dedicated ventilation unit will be placed
11. m Ventilating Single Duct VAV Systems Engineers Newsletter volume 27 number 1 Sample scenario The variable volume VAV airside system for a building is designed for compliance with ANSI ASHRAE 62 2001 Ventilation for Acceptable Indoor Quality It is controlled by a building automation system that iteratively solves Equation 6 1 to dynamically regulate the amount of outdoor air brought into the system CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 15 Ventilation reset for VAV systems Templates often include values Lew Room descaption Fumes peas for ventilation airflow To add a Templates To model ventilation reset in a G Oiee z fx fo template to your project click Hefo VAV system OES cp A Create Templates on the Cow a ine o ras Actions menu Dekio 1 fy Specify the ventilation coma IS Wel Description Length lt Dacin Gloss ce Oly Leegth Hegh f airflows cooling and ed AN PPP R heating as well as the used rr rrr a f bP fh P FP P Ps minimum primary airflow VAV min for each room VAV min sets the minimum stop on the VAV terminals It is required to model ventilation reset in a VAV bypass or terminal mixing system 2 on Choose the desired system type from the Variable Volume category 3 Open the Advanced dialog box and change the system ventilation flag control method to ASHRAE Std 62 w Vent Reset Paraiel F
12. Also if a wall is 100 percent glass the wall dimensions must still be entered Figure 6 1 Floor to floor height to wall height relationship Wall 1 Wall 2 Plenum Plenum Height Wall Height 7 ft oN The Floorto Floor Height is the vertical distance between floors including the plenum height For floors except the top floor the F T F Height is the distance measured from the floor slab surface to the bottom of the next higher floor slab surface For the top floor the F T F Height is the distance between the floor slab surface and the internal roof surface This value is used in conjunction with the entered Plenum Height to calculate the percent of non glass wall conduction load that is assigned to the return air path and the volume of the room used to calculate any airflows entered with the units of air changes per hour Wall Height 12 ft Floor to Floor Height 12 ft 6 30 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Frequently asked questions The Plenum Height is the vertical distance between the ceiling and the floor slab surface of the floor above If no plenum exists the user should enter a value of zero This value is used in conjunction with the entered Floorto Floor Height to calculate the percent of non glass wall conduction load that is assigned to the return air path and the volume of the room used to calculate any airflows entered with the units of air changes per hour
13. Jobt MD Ton Packaged Cox VOYAGER 1 YOVAGER32 Value Outside Field s Range 4 A Inghe VOW AGEA3 1 erberis eig sifi should be betvensn 12000 and 17600 A becouse Horal Cookery Faaa a wada of SEO AU Tor ned Hasir eee deed Ural Foner hose vakaa of YE Cesira Haal Gast H Note This example NCC 40 ton CEDB 76 5 CEWB 63 8 UF YC cooling NGH HC low heat Heating EAT 53 7 Power 460 60 3 a SP20 UAFD downtlow DA 19 575 To lower the airflow to an acceptable value the user will need to review the inputs and outputs in TRACE 700 After verifying that the envelope internal loads airside system and so forth have been input accurately the output reports can be focused on In this case the Temperatures section and Cooling Coil Selection section of the System Checksums report show the reason that the airflow is too large for the unitary equipment To meet the relative humidity requirements of the building the unit only has to supply air at 61 3 F Based on the room setpoint of 75 F this equates to a 13 7 F temperature difference and a high supply airflow To lower the supply airflow all the user needs to do is increase the temperature difference between the SA and room setpoint One way to do this is to lower the supply air temperature W Create Syshenrs Design Temperatures Akematrre System description PAV ATUT Datip Aa Tesrpeetatune Mis s F 5 Min 54 F Maf Maf Variable Volume F
14. Manheateg ian aa Apiay cookeg ood cirese darter Poan System Hons mf Aucaiiery lar Supply A Feat fT Revel pa ment ag T Syitene eel Wenhlahon hemmi A Ue nystem detsut cuttice ai vest fits i a rece renal vention Fie oar Sehedle Avsak 100X barge Suppl ar Ml cooing high ED ot outeide ae OD EO Tihs ifii pepeehend the comet penitence of the Gage E A aibi ard the ad Pear pare ard chou NDT ithe ong ae fie setae These conta anc grated unioni the aula cig or hig ood capacity dekio ore defied on the Danno Seiten Heating Cod haiie iaioa Scenario 3 Supply air temperature reset based on outside air temperature and worst case room loads See Figure 5 14 for a graph of the strategy Advanced Options 7 xj 1 Select an appropriate aE FTI ge V Reheat 303 Min Flow Default utilization schedule or ae ECER M eee gross form SSS Such ax pah dxtbcaion ims id create a custom schedule 77 EES i Osimo onog sf Undderficee phorum height D n 2 Uncheck Use system Duy Crete Condacive resistance of rived foo DF het FAs On penod schedie fos 0x Supply Duct Other Losses default outside air reset to pam on ms pee ea See Maima o time T mirate Downstream content leakage traction D x input a new reset schedule An i en ian E Ariy cod lan combed methodi 3 Optional Enter a aan O aaan nt cane Set Maisy Activate Alte Poenary Speer in m maximum reset differential See ore or os Matern ror
15. Norman Anal 146 i ELELEE a z u EF eS ee A a EGEE T E Therereralal Elg dipl phar 1 ER JiRpHAE a7 7 Laht Lie ija piii GE 1 Tip Gehtdue Mond Fiche Tape ACR AY 10 The differences between the alternatives lighting Ng Sohedula Mead TEE Loman Arim H ra ar Li Camie density and glass type In AIR LOW TAF ORATION Create Hoora Airis this case will be shown Pe CLL garg Tabe amined i a Clg cries W Serpe man Toc em csd Sehadue Seaileble 100k in red automatically a 10 i Y ai hargi ar hag Taba ciiid T E 0 00 W Hig Airit zj Note If the alternatives are maa ii 5 too dissimilar then all of the ROOM COMPONENTS Create Rooms Roofs Wally Party Floors Mise Loads maes cit Ag Tena sei in data will be highlighted in Aman Di TH irea UVa Agha Ball Type Sea va fee EI T red pe sth til oma Ge 100 Persicasats Ta eRe Geman Mone Hoia 6 38 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Comparing input data No or low heating energy consumption There are several reasons why an energy simulation can calculate no low amounts of heating energy despite showing realistic heating loads in the design calculation The following points are common reasons why heating energy is often underestimated Note Not all of these inputs are necessarily incorrect Some are reasons that heating energy may be minimized or eliminated Example 1
16. Occupancy capacities and schedules per space type Interior lighting power densities and fixture types per space type Exterior lighting power densities Receptacle miscellaneous load design per space type Thermal HVAC zoning determine space types with common thermal properties m HVAC system design e g system types and configuration temperature setpoints driftooints control methods m Equipment design e g manufacturer selections sequencing efficiency Local utility rate structure Energy Conservation Measures e g daylighting shading devices m Exceptional Calculation Method items e g photovoltaics Note Refer to EAc1 from the LEED Reference Guide for more information on the Exceptional Calculation Method CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 81 Modeling for LEED TIP Build TRACE libraries Open the Library Template Editor in TRACE 700 Construct any Copying existing libraries library values needed to accurately model the proposed building and adjusting their values Chapter 6 of this manual contains information on how to create may save time and provide various library values in TRACE e g schedules unloading reasonable defaults for curves utility rates unknown data Note Simply changing U values to match construction documents may not be sufficient to accurately model such components Because TRACE accounts for the thermal mass of walls roofs
17. Reduced paar C flyes Day type Cooling design weekday Denai irrg Gur orrpeak hours 11 am to dom January December Sahaday to Sunday Heating dengn Use 0 percent as the midnight to midnight cet andverne SEtting for the Saturday L and Sunday schedule The on peak period is in effect during any hour with a percentage greater than 0 Percentages greater than O are applied to the maximum demand limit refer to Step 4 on page 5 45 TRACE 700 User s Manual e CDS PRMOO01 EN Fou In the Create Plants section of your TRACE 700 project pEr 3 Choose any plant and click A i z E m m Y Enee Energy Mgmt to display ay Ar cocked pie Waeco SR Can the entries for demand ee sla eget limiting K w B zi W ater Bauder lect tace he resutance Demand imang Co 4 Specify the Maximum kW d 2 F Mammi 0 4 Cace or upper control limit for aks de Aa eini E cirian rg on Pook 6 j the overall electrical demand of the building 5 Set the maximum amount that the room temperature can drift when demand limiting is in effect 3 F in this case 6 Choose the schedule that describes when demand limiting is permitted Use the On Peak schedule defined in steps 1 and 2 7 Assign a demand limiting priority to each piece of equipment to set the shutdown order assign the appropriate priority to the domestic hot water on the Base Utility Misc Accessories tab first CDS PRMOO01 EN TRACE 700 User s M
18. Tobecacumed er at their aetauit Values Also eneral characteristics of Veriton g P r ne BOW schedules must not the office areas airflows o coe m be internal load schedules or will be input Click New Cona o vesn z E JF any schedule where the and enter Office Areas sree nee heating design day type is zero into the Description field se T oo am z This will D a e040 Input the appropriate DE co oe negiEdi airiow loans durmg the Wok sitlowiste ihe Hesing 2 acg E Pae OD e Cig tate heating design calculation For ype S ce additional details on schedules default value needs to be ee D ii Ee S refer to Creating schedules adjusted and Schedule e T e Gatton on page 6 137 for the Ventilation Repeat this for all relevant fields on the Airflow template 5 With the general characteristics for the office areas airflows defined select the Thermostat Tenplates Pro mil 7 Thermostat tab In this raco per Note Typically users need to either create their own scenario all of the rooms e E l a Thermostat schedules or in the building will be select none and let the conditioned to the same program use the driftpoints thermostat setpoints Thermostat schedules allowing a single override the driftpoints and Thermostat template to setpoints for energy analysis Themba pettirsps Colingdytub 5 F Hesngdybub 0 F Relatie humidity 0 Cooling difiport fio F Hesting dipan jes be used for
19. i Lighting fi 5 TEL Hig veni ze ereenn the refined systems in XOpi i Assign Rooms to Systems for details on how to zone rooms in ne TRACE 700 C CDS TRACE700 Projects gbXML Example tre 2i5 x TRACE 700 please refer ES a Eee ap ae es ee ee i x eo SOR OCKAeKe e STAR TRANE to Zoning of rooms on eae eate Systems Selection page 6 47 From this Monae 1 point on the TRACE 700 Sten deccioton EEEE EJ nt project file will function as a typical TRACE 700 file Note For details on creating cooling and heating plants refer to Chapter 3 in this manual For details related to inputting utility rate information refer to Creating utility rates on page 6 150 6 184 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN gbXML import and export Exporting gbXML data from TRACE 700 me IRALE 700 for exckrive use by CACDS TRACE7O0 Projects ght Exanpieire Fle Edt Actors View Options Lbearies Templates Aberatives eup Window Help Seo A Eaectkeve SRE H Project Navigator 1 Open TRACE 700 open the project file filename trc and calculate at least the design section iraki Torriglia Aioria Sahay Fier k eeve Sa HT 2 On the File menu click eee Export gbXML 3 Select the existing xml file that was used during the import process JOOTA Es bhiegle uml 4 When the export is complete the information f
20. 200 therms x 0 530 therm 300 therms x 0 499 therm 100 therms x 0 485 therm 304 20 m otal gas charges 10 304 20 314 20 6 154 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN Creating utility rates Time of day rate The time of day rate structure is shown below Electricity consumption m Customer Charge 14 00 charged each month regardless of usage m Rate 0 065 kWh for on peak and 0 040 kWh for off peak E Fuel Cost Adjustment 0 01 kWh for all kWh Electricity demand m Rate 10 45 kW for on peak and 6 05 kW for off peak Note A ratchet rate of 80 percent of the highest On peak kW demand at this location as determined during the preceding 11 billing months is also incurred Gas m Customer Charge 10 00 charged each month regardless of usage m Rate 0 505 therm Time of day Schedule E 8a m 5 p m Monday through Friday are on peak m All remaining hours are off peak Note Screen shots will only be provided for each definition Refer to the stepped rate for detailed pictures and instructions Sample calculations will be done at the end of the inputs for this rate CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 155 Creating utility rates 1 Click Rate structures on the Libraries menu The Library Template Editors program should open up to the Rate Structure library Click the rate structure to
21. 6 000 000 Btu Energy used to provide cooling 275 kWh x 3 413 Btu hr kW 938 575 Btu 6 000 000 Btu COP of chiller 200 000 Btu OPERE E oar aE PU 4 A COP of 6 4 indicates that for every Btu of energy input into the compressor 6 4 Btus of cooling are provided Depending on how COP is defined the term may or may not include the energy consumption of ancillary equipment such as chilled water pumps condenserwater pumps cooling towers and or condenser fans Note This example is meant as a generalization For the standard chillers provided in the Equipment library the chiller COP includes only the compressor energy because the ancillary equipment is called out separately via the miscellaneous accessories Therefore an overall system COP for Example 1 might be Cooling tower 50 kWh Chilled water pump 45 kWh Condenser water pump 40 kWh Chiller 0 55 kW ton x 500 ton hours 275 kWh System energy consumption 50 kWh 45 kWh 40 kWh 275 kWh 410 kWh Cooling provided 500 ton hours x 12 000 Btu hr ton 6 000 000 Btu Energy used to provide cooling 410 kWh x 3 413 Btu hr kW 1 399 330 Btu COP of chiller 200 000 Btu 1 399 330 Btu 4 3 A COP of 4 3 indicates that for every Btu of energy Input into the system 4 3 Btu of cooling are provided 6 32 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Frequently asked questions The cost of energy to meet the 500 ton hou
22. E Wall load to plenum Infity ston i Alow oraig secovery ansier al deigi Outerte ha Vary with wand ipeed T Force VAV minimum obvays gt nomina ventilation Tenan Center of lange city dang dein RTS Mest Balance M Petet design peak Fast morth Latt morth Room circulation rate Medium Dashi savings 1 Summer pood Apel September CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 11 Coil loop for exhaust air energy recovery 2 After defining the system click the Options tab and select the desired airto Click Yes to activate energy W rate Systems Options j recovery for design and energy analysis Click No to ignore xi energy recovery during the design calculation and include it only during the energy analysis _ simulation air energy recovery transfer type which determines the type of energy recovery transfer and the basic configuration In this case Coil loop series supply air tempering Note This message will only appear whenever an energy Ippo Cl kap Senet phei bag 2 ET a Supis dek C koopiast ipri da tempera Flooded ares HA DA peia Eshai dark Fisced plaste Hei JDA pic ordiri TRACE FOO 2 Salle aring meccveryArancer ot dition ho curently handed ci ors Hee Charge Lewd Parieveeters screen Wasabi yina Wot by hurt abaj recovery transfer device is added and Allow energy recovery transfer
23. Strategies that may help reduce or limit the number of unmet load hours are presented below The different approaches target commonly overlooked assumptions in the TRACE data entry process as well as the complex interactions that typically occur in building simulations Each building model is unique and as such the impact of each approach may be different In some cases the number of unmet load hours may even increase It is important to understand the underlying cause of the loss of space control rather than arbitrarily adjusting data entries to reduce or eliminate the unmet hours Note These strategies may increase the building model s total energy consumption for various reasons Step 1 Identify unmet hours The Energy Cost Budget PRM Summary report provides the total simultaneous number of cooling and heating unmet hours per alternative Although this provides a good overview regarding problematic alternatives refer to the Building Temperature Profile report for a detailed accounting of unmet hours This report lists rooms by system showing the number of cooling and heating unmet hours associated with each A section of the report displays the time of day daytype and month the unmet hours occur This information can help identify potential causes for the unmet hours For example if a space consistently has unmet load hours on Mondays around the time occupancy begins an optimum start schedule may help eliminate those hour
24. Variable primary flow chiller arrangement A variable primary flow design displaces the small inefficient low head primary pumps used In primary secondary systems The pressure drops previously satisfied by the primary pumps are instead satisfied by the distribution pump s permitting selection of larger more efficient pumps with efficiencies similar to those of the secondary pumps in a primary secondary system Variable primary flow can be used with chillers in a parallel or series type arrangement The inputs required to model a VPF system in TRACE 700 are very similar to the methods used to model a standard parallel or series chiller arrangement Figure 3 4 Variable primary flow chiller arrangement variable flow production pump gt lt chiller isolation valves DA chiller system coils 2 way control valves modulating control valve Application considerations m Varying the water flow rate through the chiller evaporator poses two control challenges for those who design and operate VPF systems a Maintain the chiller flow rate between the minimum and maximum limits of the evaporator b Manage transient flows without compromising stable operation especially in multi chiller plants CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 13 Variable primary flow chiller arrangement m Be sure to verify that the selected chilled water pump s accurately reflect the actual pump s selected
25. Z AatoAbowed 3 Waming The fadi racked iced b cone eames a an Papasten Diavetcity ren DICY ooma im x fhe SAME opersten Pane make tule za om poo ane aware of the lota cemiications Dibad fF one E Se pe bafons pou make much a change Note Since the demand control ventilation functionality in TRACE 700 requires the use of the ASHRAE 62 1 feature users will need to model demand control ventilation using a different method if both the proposed and baseline alternatives require this control strategy In that scenario users should model this feature through custom ventilation schedules Simply create a ventilation schedule matching the occupancy schedule with the only difference being the Heating Design schedule Typically the Heating Design portion of the Utilization schedule will read 0 for occupancy schedules When creating a ventilation schedule it is recommended the Heating Design portion of the schedule read Midnight to Midnight 100 TRACE 700 User s Manual e CDS PRMO01 EN Select system type Appendix G Table G3 1 1A dictates the system type utilized and how to select the appropriate type for the baseline building Table 6 2 ASHRAE 90 1 2007 systems and the TRACE equivalent ASHRAE 90 1 2007 Appendix G Baseline System Equivalent TRACE 700 System System 1 PTAC Packaged Terminal Air Conditioner System 2 PTHP Incremental Heat Pump System 3 PSZ AC Single Zone System 4 PSZ H
26. by the chiller to the heating plant 9 Add a load shedding economizer to balance the heating demand 5 32 System Control Strategies Tae Abemetive 1 Heating plat Equipment tag Gatfred bodar 1 Equipmert category Doder Ecqapeert type Gas Fred Hot Water Boer 3 Thermal stoeage i Twe e Ff Rete Fad Copacity fp fior z Schoduie Stcenpe Type E020 Hesir water cac purp Ecquipenart schade vite 1 00 Ful nad fo 4 nme Demand iming Abemative 1 Curo ES haane FG Cope UM Equipmert tog Nea recovery Chiles 1 7 m Vascuaoss EE cencerarechaies 5 i xj Oee team Pct cso aaa E ag Hea npesinnery chiki H 1 Cancel Foen Cicing Tape Hone il Pui center Ippa ane Purp Hiss 7 Purg full load anergy T fiw Mam chided waste pahit a F Loadsheddingecenomce ver 9a Evapmnive pecooing Ne x Eray soune 7 Heiney plana Hesna piara 002 Eqipmeni pchedule wade O TRACE 700 User s Manual e CDS PRMOO01 EN Load shedding economizer Daylighting Daylighting systems can significantly reduce both lighting consumption and cooling energy consumption by reducing the electric lighting heat gain in the building However daylighting can also cause increased heating energy consumption something that must be considered when evaluating adding daylighting to a building Different control strategies window configurations surface reflectivities and so forth can
27. cooling and heating loads with the desired maximum values TRACE MMI xj 4 A TRACE Chike Piia Anahy Bh vakt created sires STeecowupiled 2 Chilen Opt Teer plant configuration 6 C TRACE 700 xj a i Inter your b ra Afarian Fior khirnatia 1 7 Ce To add a utility rate that has already been input into TRACE 700 click Add Rate and select the Company if appropriate select the Time of day schedule as well Typically installed costs and maintenance costs should be input as well When finished click Apply and then click Close spear Equementinsialed cost z0 s Revenue peny f fe Corce Youb maintenance expense 25 son x Buking wea ovende fico Additional first cost fo s Building capacity ovemde 450 Unity Rate Sma Company Peneymacker Power Add Rate Uy j z Delete Rate se Note The utility rates provided with the program should never be used amp In an actual model If the entire model is 100 percent accurate except for the utility rates the results can be completely erroneous The local utility company can provide accurate rate structures for input into TRACE 700 For help inputting a utility rate refer to Creating utility rates on page 6 150 CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 115 Using TRACE 700 Chille Plant Analyzer 9 At this point the basics of zj ro TRACES 700 CACOS TRACETOD Projects ANG Chiler
28. define the control point with the coldest outside air temperature first Make each successive control point warmer than or greater than equal to the one that preceded it If you choose lt or lt as the operator define the control point with the hottest outside air temperature first Make each successive control point cooler or less than equal to the one that preceded it CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 19 Switchover control for chiller plants llas To create a switchover sequence based on the time of day 1 Select the cooling plant and open the Sequencing dialog box 2 Create two start sequences one that starts the centrifugal chiller first and one that starts the absorption chiller first 3 Pick time as the basis for switching between sequences 4 Use the start time and end time entries to define when each sequence will be used 5 When satisfied with your entries click OK to save them 3 20 Cooling and Heating Plants Switchover sequence based on time For this example the time of day determines which chiller starts first The absorption chiller starts first during the on peak period from 8 a m until 8 p m If it is unable to satisfy the cooling demand the centrifugal chiller starts and both chillers share the load proportionately From 8 p m until 8 a m the centrifugal chiller starts first to take advantage of off peak electrical rates Note
29. heat gains mM Heating Qs 2 750 Btu calculated by TRACE 700 based on heat losses E Cooling Ts 55 F Input by the user or calculated by TRACE 700 TRACE 700 User s Manual e CDS PRMOO1 EN Oversizing and undersizing E Heating Ts 85 F calculated by TRACE 700 based on the worst case room assigned to the system Cooling 1 1x SAx 75 55 500 cfm 11 000 SA Heating SA 500 cfm In this scenario the over undersizing on heating would be over undersizing 1 1 x 500 x 70 85 2 750 5 500 Btu This would indicate overheating of 5 500 Btu because the space would need only 167 cfm at a supply air dry bulb of 85 F to properly condition the space Constant volume systems supply the same airflow for both heating and cooling conditions TRACE 700 calculates the design cooling and heating airflows separately and selects the larger of the two airflows as the design supply airflow for the system This same supply airflow is used for heating design and for cooling design When multiple spaces are conditioned by the same coil a single supply air dry bulb is calculated This often will cause one room to set the heating supply air dry bulb and other rooms to be overheated Rooms that have very different thermal properties internal versus external rooms will experience large amounts of overheating as is shown in scenario 5 Scenario 6 Over undersizing on cooling for a variable volume system
30. orxo selection data and run Sas messages for each of the COOL EG COR SELECTION i ae units Refer to Additional oe a euu eae ailla items on page 6 72 for recommendations on selecting the appropriate unit for the selection results Note This example NCC 40 ton CEDB 76 9 CEWB 63 0 UF YC cooling NGH HC low heat Heating EAT 48 6 _ Power 460 60 3 ESP 2 0 UAFD downflow H DA 14 863 Elev 812 Exhaust Pwr Exh Fan Filter 2 High Eff Throw Fresh air 0 100 diff enth Sys cont VAV VFD bypass CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 71 Selecting a DX unit using TRACE 700 output Additional items 1 General rules of thumb and advice for HVAC cooling coil selections a 500 to 600 ft min for the maximum coil face velocity to avoid moisture carryover Some coils can go as high as 750 ft min Refer to the recommendations from the manufacturer b As the face velocity increases the capacity of the coil and the pressure drop across the coil increase c Fin spacing typically ranges from 80 to 168 fins per ft for comfort cooling 2 In order to keep the dry bulb temperature in the space at the setpoint temperature the sensible capacity of the unit must be at least equal to the sensible load calculated by TRACE 700 In order to keep the humidity level in the space at or below design conditions the latent capacity of the unit must be at least equal to the latent
31. 2 Select the appropriate space type These values are from Table 6 1 of Standard 62 1 CDS PRMOO01 EN TRACE 700 User s Manual Related reading Addendum 62N Breathes New Life into ASHRAE 62 Engineers Newsletter volume 33 number 1 COQ2 Based Demand Controlled Ventilation with ASHRAE 62 1 2004 Engineers Newsletter volume 34 number 5 Potential ASHRAE Standard Conflicts Indoor Air Quality and Energy Standards Engineers Newsletter volume 37 number 4 Sample scenario ASHRAE Standard 62 1 ventilation requirements will be applied to an elementary school to ensure proper space ventilation for the occupants Note Ventilation requirements can be applied either in the Airflows tab of Create Rooms or in the Ventilation templates For a discussion of templates see Using templates on page 6 129 z didi Boi deat harriei fiar iii Room daiar gelsin To ae eos Da ana Y Cancel Templates Han aupphe Aapalay munch Rasm Cirtnal Canimi Tis by caoui kad anir 1o bee pa rtrd Deiak Heating Te be caloulved bel Heating To be calculate Suiker Deina Vanir Sd BP 1AM O TTE seose swans ie J Vo Gee C x Het a a Hig lez Custom Ts Er asthe DEY Min OA laka cee py KE D lleri Silt System Design Options 4 93 ASHRAE Standard 62 1 3 Select the appropriate cooling and heating effectiveness numbers Be sure to specify a recirculation rate 4 Click Adv
32. 4 Enter the appropriate 2 Pe ee ee rook S Fad onan 52 Schedse Avatable 100 dampers values for the air reset Supply a OB cooling high 55 ak otiide a D jes schedule This shouid repeesent the combined resistance of the carpet existe and the iaised foce panal and should NOT inchude anp on fie resistance These cohok are gnered undess the aakay chy of hig cod capacity overndes are delned on the Ceeste System Heating Cod Ovemder screen Additional items 1 TRACE will not use the supply air temperature reset fields during the design simulation CDS PRMOO01 EN TRACE 700 User s Manual System Control Strategies 5 53 Supply air temperature reset 2 Donot specify a reset supply air temperature lower than the design supply air temperature 3 System types that have room controlled cooling coils controlled via the room thermostat cannot use supply air temperature reset Examples of these systems include but are not limited to single zone fan coils packaged terminal air conditioner and water source heat pump 5 54 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Supply air temperature reset Advanced Usage and General Modeling Tips Modeling examples in this chapter Modeling tips Common modeling mistakes page 6 3 Frequently asked questions page 6 20 Comparing input data page 6 37 No or low heating energy consumption page 6 39 Modeling large rooms and zones page 6 45 Zoning of
33. Add an air cooled chiller Add a heating plant Add miscellaneous accessory equipment Add a base utility Add a cooling plant Note The toolbars visible in the Project Navigator and Component Tree views are subsets of the one shown here The availability of toolbar buttons depends on the item currently selected CDS PRMOO01 EN TRACE 700 User s Manual Program Overview 2 9 Program layout Figure 2 6 TRACE 700 menus Conard Tree Eragi Trem Thubh Paria Graph Rant Dabare hdd Und Cede oa olan Copy Orec Pls Oey Fle Edt Lear Arne tears Date Lae 1 Caandars Bropect Muvipitoe Congiruclien Typ ikon Cqeenant h Chganaritinn a Ditt Tipit Conk Adri Internal ard ryw Lth Higley TE Themi Using Help Ps Hiiri Pahit Partita Conis Codda Bila APRH Farin aoa Then ene uaF ie ii Shackle Mic Aeee Shading Thiemal Storage Indernal Load Abad TRACE Ft Frodi Hia Uriari Curves Arii Tomi to CDS Wab ate Wether Teens Tonio Trans Home Farge Shes Archive Show THAO lant re IRAE 700 C CDS TRACE DO Proje itsi tutorial 2tre tre alo Actions View Options Libraries Templates ARermatives Setup Window Help Mateos TRACIG FM Chae tar Pregect Irdiarrratenn THAR Mi Load rl Tabe Weather Information copie TRACE TO Shaler Mand Analy bel Trate Terraced Dalen Here Fay aicid Cirle Craii R
34. Alcinae 1 Cooling plant Cooling plane 001 Equipment tag C wath Free Cooling 2 D gt Equpment catego Waar coea cran 4 Equapmert type 3Stege Centitugal 3 Sequenang ype Srg Heat reecton Te Ed5100 Coulrgiwe Houty ambient et bub ost SS Thermal storage Type None Capacity PO foe Schede Same My If refrigerant migration free cooling cannot satisfy the entire load then mechanical cooling is used instead CDS PRM001 EN TRACE 700 User s Manual Prt d icipion Cosirg plant 001 Pippeni Laj iibi vath Frees Cair e 0 F Load shedding economies he 0 Evapa aive poecocing e Ereng mue Flaiect conderdt hea e Figject heal to plant 7 E quioment pchedube Awadable 100 Cherries beating priri he SY Het ge rahest Ie dehur diic stion Cooling and Heating Plants Refrigerant migration free cooling 3 47 Strainer cycle free cooling Like other methods of free cooling for chillers strainercycle tree cooling acts as a waterside economizer that reduces the amount of energy consumed to produce chilled water In this case the source of cooling is condenser water returning from the cooling tower Figure 3 11 illustrates a typical strainercycle piping arrangement that provides free cooling When the ambient wet bulb temperature is cold enough the tower water is valved around the chiller and directly into the chilled water loop A filter is positioned upstr
35. BF Create Goons Airllows Pherae 1 Apo dudaanant sr karalar ban mxn Foon deurpdon EEE echo iacent an bans Templates Han suppi AT uppi l Reo E Cram Cooking aa changer he z Cooling ar hangesta Indama E Cleans z Hag P changenthe Heating 0 sr changent fates iced E Wertilaion Siei oe Apel ASHRAE Sak 1 7004 2007 15 Ca Fe Custom J m Tx Chinar Hey Ea Custom Coding fE cred pannan e ima a e Heating fe imeen POV Mins inte iea Scheie vert Schou flom mta iniba Rae fa s a a Tree Hore dhede Avai 100 AM manana Raa u few cheat Tohea da UY x Type Dst rt Lids Authors eT a at WOM Donal Bee TRACE 700 User s Manual e CDS PRMOO01 EN The button arrangement represents the typical sequence of entries but you can enter information in virtually any order Note The Project Navigator view displays the entries for only one room system or plant at a time Project Tree view organizes your entries by system zone and room The left hand pane displays a hierarchical list of all of the rooms systems and plants defined in the current project Selecting one of these items a room for example displays all of the attributes for the item in the right hand pane Refer to Figure 2 3 Figure 2 3 Project Tree view r TRACE 700 C CD5 TRACE700 Projects Tutorial42tre tre Fie Edt Adora View Optra Lires 9 Tergisles
36. Car tedhas change z m Choose the appropriate Eqametipe Ponosna 8O equipment type awh i E m Enter the heating Ermito 7 PP eceneticert x pa E capacity Hol wale pump E Select the Equipment te he e Equipment chad Gares oip hed B T operation schedule that determines when the gas fired furnace can operate P e e e ening Ferman Electne Remit nc 001 Gaited heat exchanger 002 To add equipment to a plant drag the appropriate equipment category to the configuration section 9 Switch to the electric resistance heat and m Choose the appropriate equipment type W Create Plants Heating plat Equipmert tag m Enter the heating capacity Equapeeert lype E Select the Equipment operation schedule that determines when the electric heating coils can operate Capacty Eneegy rate CDS PRMOO0O1 EN TRACE 700 User s Manual fm 9 fun tye Use these entries to move between plants and equipment respectively Heina plore 002 Eem Restas O Equpmert category Electne seuctance Eet Renace Mey 9 Thermal storage Nore Cooacty f Plot J Equipment schedule E lect Heat ached 9 System Control Strategies Morning warm up for dual fuel applications 5 23 5 24 Chilled water reset System Control Strategies Chilled water reset Chilled water reset adjusts the chilled water set point to improve the efficiency of the chiller reducing the energy c
37. Cocirg door as noted Note This portion of the schedule is used primarily to size the cooling side of the equipment during the design Rs dbio Calculation using the design weather unam w Library Template Editors POTZ 8 Bae i ee 8 CHICK New Definition to Note Enter the Start define the next set of lt time End time and Day types in the Percentage values _ amp schedule In this step the as noted Weekday portion of the m schedule will be defined to give an accurate De Dotrston representation of how ee the offices will actually be Note This portion of the schedule is occupied only used in the energy analysis NOTE The reset and lockouts we avatable for the iollowing Desk z gt i calculation using typical weather 9 Click New Definition to Sees w Library Template Editors alBi x define the next set of Men Optura Vinden Ha POT LTSI e iT IIa comar mneSw TRANE Day types IN the im Schedule Library schedule In this step the Saturday and Sunday Note Enter the Start Lise portions of the schedule time End time and will be defined together Percentage values ete oul t as noted a o give an accurate ana Saas Cae Sets representation of how aruy Decenbe the offices will actually be New Defriion occupied on the Ds detraen Coy Detrtcr weekend Reset ard lockout table Note This portion of the schedule is only used in the ener
38. E Heating Qs 5 500 Btu calculated by TRACE 700 based on heat losses E SA 500 cfm input by user E Cooling Ts 50 F input by user In this scenario the over undersizing on cooling would be over undersizing 1 1 x 500 x 75 50 11 000 2 750 Btu This would indicate overcooling of 2 750 Btu because the space would need only 400 cfm at a supply air dry bulb of 50 F to properly condition the space Note If the selected system has the ability to reheat at the terminal device this is the amount of reheat that would be done Advanced Usage and General Modeling Tips Oversizing and undersizing 6 53 Inputting the leaving cooling coil temperature will cause the same situations to occur as inputting the supply air dry bulb The relationship between the two inputs is shown below Supply Air Dry Bulb Leaving Cooling Coil Temperature Duct Heat Gain Fan Heat Gain draw thru fan configurations only 6 54 Advanced Usage and General Modeling Tips at cooling design To minimize the overcooling remove the cooling supply air dry bulb and or the supply airflow and allow the program to calculate the value s Scenario 3 Over undersizing on heating for a constant volume system with cooling supply air dry bulb entered by the user or calculated by TRACE 700 and the heating supply air dry bulb specified by the user Room 1 E Cooling Qs 11 000 Btu calculated by TRACE 700 based on heat gains E H
39. EA SA JOA F SA JOA SA Inset B parallel recovery Inset C series transfer stream to stream upstream to downstream Figure 4 3 for Inset A refer to steps 1 through 6 in Fixed plate heat exchanger on page 4 21 for Inset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 for Inset C refer to steps 1 through 6 in Heat pipe on page 4 27 Figure 4 4 for Inset A refer to steps 1 through 6 in Sensible wheel on page 4 34 for Inset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 Application considerations Coil loop energy recovery increases the static pressure on both sides of the airdistribution system supply and exhaust Contact the manufacturers of the heat exchange devices for estimated pressure drops Unlike other types of exhaust air energy recovery a coil loop recovery system does not require close proximity of the exhaust supply or makeup air streams It can recover heat from diverse exhaust locations scattered throughout the building TRACE 700 User s Manual e CDS PRMOO1 EN Coil loop for exhaust air energy recovery To model the coil loop scenario 1 On the Actions list select Change Load Parameters and define the first month and last month of the summer cooling season These entries helo determine when the energy recovery transfer device provides cooling rather than heating Related reading Air
40. Extrude deck Retan 7 outdoor m upeaan Schedin aventatie 100 5 E Create Systems Options alax Stage 2 Aino Enaigy Aecoven T ranater Nore delad Selects Cooking effectevercan af 1005 bifh Coding afectvercst at TS w 55 Heating ellectirences of 10I aati nect aliere Hating nlfectremnets al 75 ikr G eteo schecte Ev i spare slags T Aina Eray act Cooking olleckvernss af 100 arka i X Type teat pee Cenir efteckversess af 75 author Il 5 Setidedeck Pemra Heating atlectivertcrs at 100 anton 0 X Eedi Renan 7a Heating ebectiventat at 75 airflow 0 x ok Options Tempu Farsi Cok Schematic System Design Options Heat pipe 4 31 7 On the Temp Humidity tab of Create Systems input the maximum room relative humidity that the system should try to maintain In this case input 60 percent Click Apply when finished Note To further refine the model of the energy recovery device the Options button on the Options tab can be used to define such items as parasitic energy consumers static pressure drop bypass dampers part load controls economizer lockout and frost prevention 1 2 4 32 System Design Options Heat pipe Alomar 1 System desenption Restas art Single Zone Era Directirdirect Dehumdiication Methods System Siendston ont Type None Mairu roam relative humidity 7 feo x Design As Teroetanue Cockng supply Mam
41. I A i Methods press the F1 key and u click Control Method Deke Ventilation Locations Doir excel avake 100 Dai Fum ude Deck Hestrg coll avaisi VOCE Linwel Hyke tier E Ermia IEEE Create Systems Dedicated Ventilation System devciction WSHP endDOAD Water Source Heat Puro Configuration Oethuendity ard Reheat Heat Control method Foon Smtpowts Cooling Hasting Setpoint Lasts Supply ar dy bulb high lent OF ih Cooling Heating Design Setpowts Cooling epy ar dy bub 70 0 Couing seph at dew pont S OTF Coslng SA dew pot hihina OT Cooling SA dew point kow imt F Dedicated Ventilation Locations Dedicated Vertiiztion Schedules Cooling cod Avelable 100 Deck Rerun Ouadeor Deck Heairo col asveskatle 100 Level System Opona inini avvantatie 100 Seeon Opara Dedicated OA IerpHumsy If the ventilation air is to be precooled the Dedicated Ventilation Cooling Coil schedule defines the hours of available operation of the Create Systems Dedicated Ventilation 2 g F k ventilation cooling coil The optional ventilation Akamaive System dexcieton WsiP a00 gt COOTINg coil is available for any hour that this schedule reads 1 percent or greater Configuration Ostusenndty ard Reheat Heat Ferre titre ice lem reo If the ventilation air is to be prehea
42. If the people schedule reads greater than 5 percent the cooling thermostat will try to control the room to the design setpoints The Thermostat schedules allow the user to enter heating and cooling setpoints based on time instead of occupancy Thermostat schedules are created using the Library Template Editors program Note If a cooling thermostat schedule is selected other than the default None the program will ignore the entered cooling setpoints and driftpoints for the energy simulation However the setpoints will still be used during the design calculations The heating thermostat schedules and driftpoints work identically CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 29 Frequently asked questions Q What is the difference between Floorto Floor Height and Wall Height and how does plenum height work in conjunction with these two inputs A The Wall Height is used to define the size of the exterior wall exposed to ambient conditions and solar loads Wall Height Is multiplied by the Wall Length to calculate the gross area of the external walls This area should include any window area and the wall area above an acoustic ceiling the plenum if it exists Unless the user has unchecked Wall Load to Plenum the load for the portion of the wall above the acoustic ceiling will be assigned to the plenum during the heat balance calculations assuming that the entered plenum height is greater than zero
43. Mth oversizing amount For example a chiller plant consisting of two same sized chillers tax WOuld set each chiller to 575 for a total plant capacity of 115 lemy Lpspaent Grii Uiii 7 Mii Acitziiry Compressor only energy rate In TRACE the Energy rate entry under the Cooling Equipment tab of Create Plants describes the compressoronly energy rate for the piece of equipment This is important because the efficiency reported for packaged systems e g rooftops water source heat pumps packaged terminal air conditioners etc often includes fan condenser and compressor efficiencies Users may enter the EER or COP value found in the ASHRAE 90 1 2007 equipment tables and define which components are included in the energy value TRACE will use this information along with the associated component energy values to break out the compressor values for the equipment calculation 6 96 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Modeling for LEED sida ogir Equysiend Alheira 2 Heat Hrorcinn Cenir pled Fat biirr syslen f Tae 001 Minds Cooked Condenser F Equipment tag Ftot baseline gstem Houh ambene OOT ie Catngary aroos utp Eqamentipe S014 MinAC SS SP Oth WAY gt 700 b Thema Storage NewEaup Seqencngthee Seve ttti i s we e o Ewen ee fet deo Fleject condencerhest Heat cqacioneapyereet Scheie Some y l mao fg E Pa
44. Note Use the basic how to instructions in this chapter to help you model typical system level control strategies Each example begins with a brief description of the control strategy followed by a sample scenario that illustrates the entries needed to model it Typical values are suggested where appropriate CDS PRMOO01 EN TRACE 700 User s Manual System Control Strategies 5 1 Airside economizers When ambient conditions permit an airside economizer cycle brings outdoor air into the building to provide natural non mechanical cooling Operating the mechanical cooling system less reduces utility costs One way to control the economizer cycle is to monitor the enthalpy of the outdoor air and compare it with a predefined limit As the ambient enthalpy drops below this limit the position of the outdoor return air dampers modulates to maintain the desired supply air temperature Designers often set a conservative limit for economizer cycles based on outdoor enthalpy If improperly adjusted the economizer cycle may actually increase the mechanical cooling load Comparative enthalpy control takes better advantage of natural cooling by monitoring both the outdoorair stream and the return air stream The outdoor return air dampers are then positioned to use the air stream with the lowest enthalpy Figure 5 1 Airside economizer supply duct supply air central air handler with comparative enthalpy control return air
45. OADB and units entries define the temperature that determines when each sequence will be used The program ocks in the first operator you choose gt lt gt or lt for the remaining entries This helps prevent gaps and overlaps in the switchover conditions 5 When satisfied with your entries click OK to save them Switchover sequence based on outside air temperature The dry bulb temperature outside determines which chiller starts first in this example At outside temperatures up to 85 F the centrifugal chiller starts first If it is hotter than 85 F the absorption chiller starts first Both chillers share the load proportionately if the chiller that started first is unable to satisfy the cooling demand Abomstrve 1 Equpmert Category Configuration EN i n Cooler plants ose ae ear cS at lt la ee A r a aA Chiles 1 elec contihupal coed A Chex t Waterco p peme airy e Chau 2 deect fred absorption Plot Wired Heating plants amp iy m la Heating plare 002 How Cig Piara Wate Boder Electr Gsrtred tawe he fecutance hes exc n es qt Ed A gt a Sequencing i xj Da 5 Bane Co Chater T jelet arinaa Cier 2 irera abrir i Cancel Eney Mgmt 2 Cher 7 pieacima ahan Chibe 1 aise carinha 1 Sequencing pe Utiy Misc Accessory Habe Enter sapara crisis mire balaa Onder The frit cienia treated be used If you choose gt or gt as the operator
46. Schedule Aredabily i00 ist gi Select System Exhaust if main system exhaust is used exclusively as the exhaust side E Select Room Exhaust if the room exhaust airflow is used exclusively as the exhaust side Room exhaust airflows are input on the Airflows tab of Create Rooms If no room exhaust is input then all exhaust air will be at system level m Select Return air if airflow returning back through the plenum or return duct pre system exhaust and post room exhaust is used as the exhaust side Create Systems Options Abemetrve System description fwsHP wth DOAS Stage 2 Atoka Enaigy RecowenvT canater Type Nore jdet ual Supside deck Yori bites z upede deck Vertiston doaewntbean ha Exdrede dack 5 yiten vod vest Schedin avedatie VK gt 5 _Ltteciveness Osters System Design Options Sensible wheel 4 37 6 Input the effectiveness of the sensible energy wheel essentially how efficiently the wheel recovers energy by clicking Effectiveness and entering the sensible effectiveness percentages at different airflows Click OK and then click Apply when finished Note To further refine the model of the energy recovery device the Options button can be used to define such items as parasitic energy consumers static pressure drop bypass dampers part load controls economizer lockout and frost prevention 4 38 System Design Options Sensible wheel Cocke efhectivereat
47. TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 93 Modeling for LEED Note Fan placement in TRACE depends on the system type selected m Packaged Terminal Air Conditioners and Incremental Heat Pump systems have fans at the room level The Single Zone system has a fan at the zone level E All VAV systems used to model Appendix G baseline systems have fans at the system level This distinction is important when analyzing the automatic fan sizing feature in TRACE The system fan power is determined at the level of the primary fan Therefore the primary fan for an Incremental Heat Pump system is at the room level which means that the equivalent Appendix G system fan power value will be calculated on a room by room basis for this system Refer to Zoning of rooms on page 6 47 for more information Equipment designation As with the system type the type of equipment used in the baseline building is designated by Appendix G Table G3 1 1B Details regarding the particular equipment types can be found in Section 6 of ASHRAE Standard 90 1 2007 C D S offers 90 1 2004 and 90 1 2007 Minimally Compliant Equipment Libraries which include the equipment found in these tables Before selecting equipment the baseline equipment capacities need to be determined equipment types are categorized by size in ASHRAE 90 1 2007 Section 6 Appendix G requires both the cooling and heating capacities in the baseline building be
48. TRACE 700 User s Manual e CDS PRMOO1 EN Desiccant dehumidification orl To model desiccant dehumidification which is a means of removing latent heat from an air stream begin by modeling the air distribution system 1 Choose the desired system type from the categories listed For this example select Series Fan Powered VAV from the Variable Volume category Typical applications for desiccant dehumidification include ice rinks Supermarkets retail clothing stores and clean rooms as well as installations in humid southern climates In each instance desiccant dehumidification provides independent control of sensible and latent heat without the need for reheat It also dehumidities the supply air stream without lowering the dry bulb temperature Application considerations Desiccant regeneration commonly requires high temperatures which incurs a significant energy cost Exposure to contaminants clogging and thermal stress causes desiccants to degrade over time One should consider space requirements cost and added pressure drop when evaluating whether desiccant dehumidification is practical for a particular application Related reading Dehumiditication in HVAC Systems Applications Engineering Manual Trane literature number SYS APMO004 EN Sample scenario The ventilation deck of the airdistribution system for a building includes a solid desiccant wheel with an integral run around coll loop The wheel only ope
49. Topic Supply air temperature reset based on worst case Scenario 1 page 52 room Supply air temperature reset based on outside air Scenario 2 page 53 temperature Supply air temperature reset based on outside air Scenario 3 page 53 temperature and worst case room loads Note For further discussion of creating utilization schedules refer to Creating schedules on page 6 137 For further discussion of creating alternatives refer to Creating alternatives on page 6 131 Scenario 1 Supply air temperature reset based on worst case room F Create Systems Diplions Abana 1 Sytem dezerptisn MEE o vaiade Velma Pehea 30 Min Flew Deliut Lie gt Evapa Coning Economie j Type ns Type Noe Advanced 1 Deset eiee POOO wea D F TT KK ip Stem descioion VAVRehaat Sytem type Variable Volume Rehaat JOX Min Flow Defaut Cancel j In Sohedes Dirplacement Veriiaion Unerik Parameters Hehi purge On 0 Supely ak path duct location Reiu Ar m Shag Optics wart Jou ox Space sorbilo gam to occupeed layer S Ty Optimum step On ore Underfioce peraan height tt Duty Cycling Conductive rometarce of teteed floor he fF Bn Ori petied schedule ow 0 Supply Duct Other Losses amp Potten length Trametes Upstream nomnal leskege bacton 0 x Maiin oll tee matet Dorentreem corntart leatege frecton 0 S o jL P Maday Cooking cod losses to plenum 0 x Men E Ea m Anndy col la
50. Vent 300 m Infiltration 0 cfm ak nice Min StopsRh m Room Exhaust 250 cfm Return 780 Exhaust 40 Em Exh 240 m transferred Air 0 cfm A 6 64 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Balancing airflows Based on these inputs TRACE 700 will calculate Room 7 exhaust air ventilation infiltration room exhaust 200 0 0 200 cfm Room 1 return air supply air infiltration room exhaust 1000 0 0 1000 cfm Room 2 exhaust air ventilation infiltration room exhaust 300 0 250 50 cfm Room 2 return air supply air infiltration room exhaust 1000 0 250 750 cfm Scenario 6 One room with room exhaust and air transferred from the adjacent space Room 1 E Ventilation 250 cfm m Supply Air 1000 cfm E Infiltration 0 cfm E Room Exhaust 0 cfm m Transferred Air 250 cfm Room 2 E Ventilation 0 cfm m Supply Air 1000 cfm E Infiltration 0 cfm mM Room Exhaust 250 cfm m Transferred Air 250 cfm CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 65 Balancing airflows Based on these inputs TRACE 700 will calculate Room 7 exhaust air ventilation infiltration room exhaust 250 0 0 250 cfm Room 1 return air supply air infiltration room exhaust 1000 0 0 1000 cfm Room 2 exhaust air ventilation infiltration room exhaust 04 0 250 250 cfm T
51. cooling and heating plants 12Drag each coil in the Unassigned Systems Coils pane to the appropriate plant in the Systems and Plants pane The illustration labeled After shows the completed assignments E Create Systems Fan Ovenides Albematne 1 Syibem depcription bs HP ard DDA Fan cpcing schedule Cycle path diougani weber Source Heat Pump ooe kis Cini eT OO lem ile 10053 ef Aacookd Abcockd Waeco chart ur ay ch rn Electne resutance oh Waterco urdaty 66 Gartred rest exchanger F a Prunet kil Avaliable 100 kw Ere 100 kw Avweodable 1000 Ting Awada 100 Kiel TE Avvedsble 100 1 plants lls Cooling part 1 fhest pumpa d WSHP 1 Mas Cooling part 2 IDedceted DA un B Dedcoted OA un Heating plants 10 Plot Wired Now Cig Plart Mew Hig Ms Heating plant 1 hest pump bop 9 Bi Goted bols fhos pumo loop New Hig Par lls Heating plant 2 Dedicated DA un fee Geoteed heat exchanger roottop For cooling use water source heat pump and air cooled unitary For heating use boiler for the WS system and gas fired heat To asagn equgment dag he deed equen excha nger E Man Cocing Cad E Optional eain Casing Cod EHE Hesting Spclen WHP and DOAL Bf Man Heating Col F Optional ean Heati Cod Before After CDS PRM001 EN TRACE 700 User s Manual Ti Cooling plant 1 hest pump
52. method Also ensure the Type reads Active Chilled Beams 4 Select the Auxiliary heating coil type Note Unlike other systems Cooling supply and Leaving cooling coil temperatures found under the Temp Humidity tab entered by the user will be ignored for both passive and active chilled beam systems TRACE 700 calculates the supply temperature based on the upper limit of the room dew point plus a safety margin 5 On the Fans tab choose a fan type for the primary air handler fan 6 Enter a static pressure for the primary air handler 4 82 System Design Options Chilled beams Dissi efficiency Dipset ood echediule avadatte ona Indet elficioney T x imici coll sheds Avait 1 0D os 1 Auna Ae Daira Giessen Trends Dias Pea As aiia beeen Toes Duty Cycling Conductrve senstance of ianed foce firs hel F B Un period schedde On 0 vj p See Duct Othe Losses Patton length trerefos Upetesn nomnal lock age factor hb x Maman off time E mtes Dormwrean constant leakage fracton Poom X D J Liming Pierii z Atscbary Coukrg Cod bare to plenum fo 3 Main coding tan Poom exhaust ton ahd z Method E Main heating fan ee Auadany cooling col Piictre ate Biter Pray System Chledfeans Ansceaty tory Auadiary heating col Actrate Amer Prnary System e 4 Supply Ae Retret F Amdy lan No Fan Schedte Max Rest eS rm
53. plants they are assigned to thus increasing the plant size automatically Changing equipment capacities under the Create Plants section of the program has no impact on the system simulation unless you have checked the box to link the equipment capacity to the system coil capacities on the Change Energy Parameters screen If you have already adjusted the capacities of the coils in the Create Systems section the plant linking feature should not be utilized Generally the equipment Capacities are only used for energy calculations It is important to verify the increase in capacity is realistic given the building design properties LEED template submittal The LEED version 3 EAp2 and EAc1 templates provide guidance on the reports to include with the submittal Aside from those required the following reports provide information reviewers may find helpful Room information from Entered Values reports Plant Information from Entered Values reports Library Information from Entered Values reports System Checksums from Design Reports LEED Energy Performance Summary Report from Analysis Reports E PRM Fan Details from Analysis Reports Additional LEED credits TRACE can help provide information to qualify for additional LEED credits For example under the LEED New Construction version 3 rating structure TRACE may help with the following credits CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 107 Mode
54. primary fan the fans in the Fan Coil units and the TN E kiwi Avvelable 100 optional ventilation fan i i ee ial f Metha keim delish iig the fan in the dedicated spiemehant N Ke ies Pogmexhovit_ __ t Kestim Avedstle 100 ventilation unit ie t e CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 65 Dedicated outdoor air systems dhs Next define the cooling and heating plants represented by the fan coil system and the rooftop air conditioner 9 Add two new cooling plants and two new heating plants to the Configuration pane 10Drag the appropriate icons from the Equipment Category section to define each plant 11 To finish defining this equipment enter the information from Table 4 9 on page 4 66 on the appropriate equipment tab Finally assign the coil loads of the air distribution system to the proper cooling and heating plants 12Drag each coil in the Unassigned Systems Coils pane to the appropriate plant in the Systems and Plants pane The illustration labeled After shows the completed assignments 4 66 System Design Options Ademaive 1 Equipment Category Configuration Cookery planes Ghose Fi a ET wt i ta Corann chiles plani Eon Aacooled Abcocled W Ww Watercooled chis j uiay preg et laes Mas Cooling plart 2 dedicated QA uni Piara Wizard 10 E Dedcoted OA un 1 Heving pirts iem Cg Pin kJ 166 lat
55. same name plus trc at the zj end and convert the lds OF Tey ire LNG boot d protec a created wah an cr ero of tha udus Piles reihi wath Tears haws We ta Droge te valle srved ard a ER ila nay file to a trc file In this itar orcs Ha wll ba novel ae a case the file ASHRAE Oe you wich to upgrade your project ree 4C 62 lds would become ASHRAE 62trc trc CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 189 Importing a load design Version 3 x or Version 2 x file 6 190 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Importing a load design Version 3 x or Version 2 x file
56. simulation Note This message will only appear whenever an energy transfer device is TRACE PDO SP alive energy eani at dation i currentty hard of kon d Ua Che Lid P hr i hirea ed ria bee bo huri on Boreate Systems Options dhama 1 yitam derenp on ipiam 00I Evapa Coning Type Bore Dosa elfsceeraae x Drazi fed ichadud T Indirect oliris fF 2 z added and Allow energy recovery transfer during design calculations is turned off Select Ventilation upstream if the device is located in the outdoor air stream and upstream of the optional ventilation coil Select Ventilation downstream if the device is located in the outdoor air stream and downstream of the optional System Design Options Trivett cated iid ef her ventilation cooling coil Select Return outdoor air downstream if the device is located after the mixed air stream downstream of the main cooling coll Select Return outdoor air upstream if the device is located after the mixed air stream upstream of the main cooling coil Sage 1 atoia Energy Aoig T ranae r Seale chee Gr word chock Supaidedeck Vein ae A Esha dock De ii a Sehed avais p Note If no optional ventilation system has been input then Ventilation upstream and Ventilation downstream will function identically If the main cooling coil has been deleted or if the ventilation deck location on the Advanced window in Cre
57. water cooled chillers define Eaim iag Ode 1 bronto J tt each chiller ne C 2 If the plant contains more than l l aoe Dy OE piece of equipment specify cocu 7 1 Define the first chiller as an the capacity of each machine absorption machine 2 Pick Series as the sequencing type i 3 Enter the capacity of the pdam Eea r m condenan wai auai Creat vol ond water purap chiller condense 4 Specify the full load consumption of the For chillers piped in series define only one primary dedicated condenserwater chilled water pump For the other chiller pick None pump and the shared chilled water pump 5 Switch to the second chiller and repeat Steps 2 4 to define it as a centrifugal chiller Abemative 1 Cooling plant Cosina pare 001 Heat rajacton type E5100 Conling tower Equiomentiag Crider 2 cerrig 5 Corcel Ecumpmert category water cooled crae Thomai stonge Equpmert ype 3 Stage Centtupsl lt i C New Laie ama 4 6 Pick None as the type of primary chilled water pump Note If a user has chillers in series with a 10 AT the program will automatically adjust it to 5 AT However if it is anything other than 10 the program will use that entered value For example if chillers each have 12 AT the final Choosing None indicates that the leaving temperature will be chiller shares a pump already defined 24 colder than the entering for this cooling plant temp
58. 100 cu ft Aor of natural gas wood water 1 000 gal 1 000 gal hr purchased steam hot water or chilled water therm therm hr process load steam or hot water therm therm hr process load chilled water ton hr ton other load therm therm hr To model plant level options such as plate and frame free cooling waterside economizer or piping arrangements be sure to identify the option or arrangement for each chiller in the plant By default the order in which you add equipment to a heating or cooling plant becomes the equipment start sequence Coil loads Coil loads cannot be assigned to Individual pieces of equipment they can only be assigned to plants Create separate plants to distribute the coil loads across multiple pieces of equipment For example to assign the main cooling load to a chiller and an optional ventilation cooling load to a rooftop air conditioner create separate cooling plants for the chiller and rooftop air conditioner To properly model the coil loads for a single zone SZ system create a separate zone for each SZ system in your project Then assign the appropriate rooms to each zone To model a heating and ventilating only system that Is an airside system without a cooling coil select ventilation and heating from the heating only category of airside systems To model a variable volume variable temperature VVT system such as the Varilrac changeover bypass system select one of the changeover bypas
59. 57 F Mn fs Maj Min Maf F Mmi fF Man cooing cod marnmaum allowable bove a then Grotting a chilled mater cod downward dang dehureiicabon of veld cof mode Variable Fan Speed lor capacity control System Simulation only Number of fan speeds i Percent atflow at low speed x Percent autlow at medum speed x Hutediicaton Deng humedity 1050 diterence gart Mrara 100m relatrve hezredty x Selection _ Options DedcotedO4 Temp Humidity Supply duct bempersture fos F dterener Additional Items When adding a heat pipe to an airside system it is recommended that the minimum and maximum cooling supply air dry bulbs be set equal to each other to fix the value for the cooling supply air dry bulb This is suggested because TRACE 700 cannot osychrometrically solve for the cooling supply air dry bulb when an energy recovery device is attached to the Return Outdoor deck For the ramifications of fixing a cooling supply air dry bulb please refer to Frequently asked questions on page 6 20 and Oversizing and undersizing on page 6 51 Energy recovery transfer devices are generally applied at higher airflows higher face velocities than what the manufacturer submits for ARI certification For example if a heat pipe is rated at 400 fom a typical sensible heating effectiveness is around 50 percent However it is likely that this device will be applied at a much higher airflow 600 700 fom which will
60. 60 while minimizing energy USE The system controller determines the highest possible cooling supply air dew point setpoint that still avoids the relative humidity from rising above the maximum upper limit 60 in our example in any room When the outdoor dew point is greater than the current cooling supply air dew point setpoint the dedicated outdoorair unit will dehumidity the entering outdoor air to the cooling supply air dew point setpoint When the outdoor dew point is less than the current supply air dew point setpoint and the outdoor dry bulb temperature is greater than the cooling supply air dry bulb setpoint the dedicated outdoorair unit will cool the entering outdoor air to the cooling supply air dry bulb setpoint When the outdoor dew point is less than the current cooling supply air dew point setpoint and the outdoor dry bulb temperature is less than the cooling supply air dry bulb setpoint the dedicated outdoorair unit will heat the entering outdoor air to the heating supply air dry bulb setpoint TRACE 700 User s Manual e CDS PRMOO1 EN Dedicated outdoorair systems This example will cover how to model the airdistribution system steps 1 8 model the cooling and heating equipment steps 9 11 and assign the loads from the coils to the equipment step 12 Aleinaire 1 Syshem desertion VAH and DOAU Vamable Volume Rahast 20 Min Flow Datak 1 Start by selecting Variable Volume Reheat as the system type
61. 7 Define the attributes of the ice making chiller type sequencing capacities and pumps 8 Choose a schedule that makes the chiller available for thermal storage 9 Pick the new thermal storage type created in Steps 4 6 to define the storage parameters 3 26 Cooling and Heating Plants Thermal energy storage E thermal Storage Library Schedule tock E TANES 5 Shope Tanssi am ice re Coragi mpe Ful charge Typa Z seine 5 Mama kopa p few vant oe 5 Flat Propertier If desired rename the equipment type and add a brief poih Brit F description Deny E ew Deesage chet T F Sehedule Dalinitisn Start Ered Howth oe The ICETANKS schedule melts ice discharges the tanks from 10 a m to 6 p m and makes ice charges the tanks from 6 p m to 10 a m Casing plant O01 Equapererd ag leering Cet E gaper Sobegeny water cooted cha JE ln Doo Cooling Cquipareent Controls E x ee Pint decipere Casing plant 001 Equaprrend tag loeerrusking Chiller Cancel Free Cooling Type A When modeling an ice making Phi cocker type fe hiller r ify the _ E chi Sp SESW ape y ATR 8 respective capacities and energy rates for cooling ana Semeen f j i Losd shedding eponimas Ho tank charging operation Evepautivepecading ic i Eneng muse Faial Gonderdas heat Haa rejechon Aguia z Figject heal to plant E quoment oc
62. 700 User s Manual e CDS PRMOO1 EN Dedicated outdoorair systems Dual Path Air Handler Split Dehumidification Unit A dual path air handler split dehumiditication unit separately conditions the outdoor and recirculated airstreams within the same unit Each airstream has its own cooling coil but a single constant volume fan serves both paths Figure 4 16 Split dehumidification unit Sample scenario A large meeting room is served by a dual path air handler split dehumidification unit During the cooling season the dew point of the air leaving the outdoorair cooling coil is adjusted to prevent the relative humidity in the room from rising above 60 The return air cooling coil is then modulated to maintain the space dry bulb temperature at setpoint During the heating season the outdoorair heating coil heats the entering outdoor air to 55 F dry bulb m he system controller determines the highest possible dew point leaving the outdoorair cooling coil that avoids the room relative humidity from rising above the maximum upper limit 60 in this example m VVhen the outdoor dew point is greater than the current cooling supply air dew point setpoint the outdoorair cooling coil will dehumidity the entering outdoor air to the cooling supply air dew point setpoint The return air cooling or heating coil modulates to maintain the space temperature at setpoint CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 67 Du
63. A enaives Setup Widow Help ie ES OR cee AeVe2e FS F5 2B TRANE le ls p g T Elg Mala a Project Tree View In the Project GP tity Ratet amp Lite Cycle Cott R Navigator view a Enw Hon Figure 2 2 on Bc Systems xrm ard rooms r pases page 2 6 the entries E Claseroom 102 poly a EB Clarmoom 103 at the right are distributed on several 3 E Casom 104 3 E Room 100 Administiation pyy eire 3 E Room 110 Tech Shop ce ve columns of a 4 Eg Room 111 Music Room Man Supp 2 E Caferesia mma Hen worksheet A Peele b Lighting Muceloreou Lood Q Roots Q w CDS PRM001 EN TRACE 700 User s Manual Program Overview 2 7 Program layout 2 8 Program Overview Program layout Component Tree view organizes your entries by attribute Selecting an attribute room airflows for example displays all of the airflow related entries for all of the rooms defined in the current project Refer to Figure 2 4 After completing the entries in the Project Tree or Project Navigator view use the Component Tree view to check your work or make changes to a single attribute for multiple rooms Figure 2 4 Component Tree view ne TRACE 700 C CD5S TRACE700 Projects Tutorial42tre tre z lajxj Fie Edt Adoma View Options L rais Tempides Wirow Help OsBa rte eeimne TRANE Component Tree View Alternative 1 Eneegy More E Bes Contra piris Mas Phares D Bes Hooter pirt wiis Phar
64. A chilled water plant consists of ice storage tanks and two 500 ton chillers that are piped in parallel During off peak periods a dedicated ice making chiller recharges the tanks while the cooling only chiller satisfies the off peak cooling load During on peak periods 10 a m to 6 p m weekdays only the tanks satisfy the cooling demand both chillers are off If the tanks cannot handle the on peak cooling load all of the ice melts the cooling only chiller satisfies the remaining load Mls This thermal storage application uses two chillers eae but only one chiller makes ice qipmeri Category 5 Cooke To model the plant A Am cg wo Mas Coning plat 001 Aacooked Ai coced Waterco Waterco EY Coalng only chiles chiles uray chiller untey H g Cooling tower 1 Add two water cooled g a 1 art parla 4 16d i gt f Coding tone chillers to the cooling plant on hm name Replace the generic tags oe 5 las Hewting Poet 002 use Cooling only chiller i e F amp To change an equipment tag for the first machine and amima M O age select it and then either A lick i in or click Edi Ice making chiller for the CICK ragain or ECK Eeit ig ather edit the selected text To stegn equpment dag the dained equpirari calegory lo the conhgzson bee 2 The order in which you add Configuration equipment to a plant establishes the default start sequence Refer to Switchover control for chiller plants on page 3 In a
65. Aaina Mincellansqun sppeppoier Plant Equpeerting Tape Energy Schedule ra Hine E Gallons is not a valid input for a domestic hot water base utility because the program does not know the change in temperature that will occur to water traveling through the heating equipment To correctly model domestic hot water input the data using units of therms kWh or MBh The user can also create a custom base utility in the libraries with units of gom and input the delta T across the waterheating equipment Energy Only CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 17 Common modeling mistakes Economics and utilities Eq emertinetsiedcot E a Revenue penshy fp fs 3 Youb maintenance expense 0 Is 7 Budding aes ovenide fo E Addcesl first cost 0 fs Buking capacty ovemde ken Recumng Additional Depeecishie Cost You Econ Cos incs Lie 10000 Econcenc le fio Yes Yew cot 515 Depe te taxes 10 Yes maned Utility Rates amp Lile Cycle Costs m Ihe default utility rates have been selected Creating a custom utility rate and if applicable a Time of Day schedule in the Library Template Editors program will result in more accurate estimations of the energy costs Please refer to Creating utility rates on page 6 150 for instructions on creating your own utility rate Energy Only m The utility rate has off peak rates entered but there is no Time of Day schedule
66. Argad Rooms Use Ak imatiwe 1 EJ Assign Sytteme to Plants System Arsyen s Syrtem Aragmens No disty sates drte No ulity idea drte E Define Economics as as FI Cokie orsi View Rosu s 06 11 2103 09 25 AM E T 7 203 8 25 AM Ont se ay ys wy Oe apne so Daylighting Parameters E i i j General Quyaghing Contests Floom Pisearrstras Glas Parameters intemal Shade Parameters Daylighting Geometry Type Note Inside Visible Reflectivity for Floor Wall and Partition are defined via the Advanced tab in the Construction ibrary and can be overridden on the Construction Parameters tab TRACE 700 User s Manual e CDS PRMOO01 EN ee Daylighting Parameters a General hapaghinng Cindseds Room Persies Gies Parameters intemal Shade Panamaters 5 Daylighting Geometry Type Atmospheric Dekhi Geometry Tyge Moisture Atmospheric GLS Oat Onire necem band an gave dimansion Turbidity and Inside eek aa Note Recommended values and Visible Reflectivity are oo EE typical ranges for these values can input from the General tab be obtained by accessing Help ae Q Ae Tutadly press F1 Note Select the Daylighting o E Geometry Type that reflects E how the glass was input in feeb Note Inside Visible Reflectivity for this example as GLAS DIM Cira om Floor Wall and Partition are eatin defined via the Advanced tab in the Construction ibrary and can be overridden on the Constructio
67. BF create Systems Options Advanced Options Abemar 1 Choose Supply via oe EE a Perr ao Sidewall Displacement Ventilation Oeaphacement Vertiahon Urederiog Parameters Supply ar path duct location Supply vis Sideral Duplacement Vertiaton 3 Space sernbie garis to cocugeed layer Urdaia piorum height 0 a Conductive resistance of rained floor 075 be fF Alba Supply Duct Other Losses Upstream nomnal leakage hachon Dewneteam corntant losk age hacton Pasdbary Cooke cod bases to plenum aha io ana z Manhestingtan DOE OOo OL el aed Cae Prce tel Adboyion Aasdhary heating cod Activate Alter Prenary System Wat Corvec gt Surely Aa Reret F Pasdbary tan sfa o del System evei Ventignon Ovemdes FF Use sytem dedah otide o reset Aafia pesna r praat Sup sr DD coolinglow ot outside 0b T Schedule Avaiatie 100 damper Supply si DD cooling high at outside DO This shouid sepresert the combined sesistance of the carpet Hi ests and the aised floor panel and whould NOT inciude any a film resistance These controls we ignored untess the mudkery cig o hig cod capacity ovemdes are defined on the Create Systeme Heating Cod Ovemides screen 4 On the Temp Humidity SS create Dretara Daas Ta tab enter the appropriate Cooling supply temperature for the revlon ion bt Type Fena aie bypace wath wie cod leaving temo system Heder 1ocen rallia humidi No
68. Chiller plant arrangement may also play a role in energy use To avoid condensation chilled beams must be supplied with warmer than normal chilled water temperatures When coupling chilled beams with a traditional air handler for the primary air TRACE 700 User s Manual e CDS PRM001 EN system designers may choose a dedicated chiller arrangement one plant delivering very cold water to the primary air handlers and a separate plant delivering warmer chilled water to the chilled beams or a shared plant serving both chilled beams and air handlers Consider the advantages and disadvantages of both options when determining your plant configuration m Due to the potential for condensation special consideration should be given to the geographic region where chilled beams are employed Sample scenario An active chilled beam system satisfies the ventilation and cooling requirements for an office building Supplemental heating in the form of radiant floor heating will be included to satisfy any heating requirement the primary air system is unable to handle To model each active chilled Pi create Systems Selection beam Aemative 1 Sydtem ecco CE Fuckers Chlad Beart 1 Create an airside system and define it as Active Chilled Beam Active chilled beams are zone level coils CDS PRM001 EN e TRACE 700 User s Manual System Design Options 4 81 Chilled beams 2 Click the Options tab and click Advanced Options 3 Select the control
69. Condenser tame Despena 5 F Minimum pasing 75 2 Rejci conden hes Te misenns ppi Hr epenn egemen TRACE 700 User s Manual e CDS PRM001 EN Cooling tower with VFD A cooling tower rejects the heat from a watercooled condenser by spraying water over a fill while drawing outside air through it As the heat rejection load and ambient wet bulb change the cooling tower fans must move either more or less air to produce the desired water temperature One popular method for controlling the speed of the cooling tower fans is to use variable frequency drives VFDs This approach offers several benefits E Tight control of towerwater temperature Fan power varies with the cube of the speed resulting in great potential for energy savings m In addition to avoiding gearbox or motor wear fans operate more quietly at low speeds when equipped with variable frequency drives than with other methods of modulation Figure 3 14 Cooling tower with VFD spray propeller fan X outside air from f condenser condenser Application consideration E Balancing chiller and cooling tower energy is an important aspect of controlling condenserwater temperature Studies indicate that during many points of operation the optimal condition is not the lowest water temperature that the cooling tower can produce To reduce the combined energy consumption of the chiller and tower consider using automated system level controls to
70. Cooling schedule Cir x Heong schedde Hsia 2 Room 1 The default values for the thermostat driftpoints 90 F and 55 F respectively are being used This means that whenever there are 5 percent or less of the people in the space determined from the people schedule the room will be allowed to drift up to 90 F or down to 55 F before the equipment turns back on If the building control system is not going to allow the room setpoints to setback this far or at all the default values need to be set to more realistic values 2 The selected Thermostat schedules allow the building to drift to an unrealistic temperature at night For example the CSTAT and HSTAT schedules will allow the building to drift up to 95 F and down to 55 F depending on the time of day The values used in the schedules can be viewed by clicking Schedules on the Libraries menu and selecting Thermostat as the schedule type Typically users need to either create their own Thermostat schedules or select none and let the program use the driftpoints the schedules override the driftpoints Not correcting this input will result in an underestimation of the cooling and CDS PRM001 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 39 No or low heating energy consumption heating energy at night Refer to Frequently asked questions on page 6 20 for information regarding how driftpoints and thermostat schedules interact 3 Large areas ar
71. Engineers Newsletter volume 29 number 2 Sample scenario The airdistribution system for a building consists of series fan powered VAV terminals rated for 0 5 in wg static pressure anda variable volume forward curved FC fan sized for the system static pressure of 3 in wg Chilled water produced by a three stage centrifugal chiller that consumes 0 7 kVV ton at full load cools the supply air to 45 F Abematve 1 System description Cokd an Syiner Seems F arrPoweed VAV Doai wiener r ay Min Flow Delak Changeover Dypors ChargrorsBpar VAV wah Local Mes Rehey System description Cotas System j Soins Fan Powered VAV Desn As Lempeiohae Drectlexirect Dehurediicabon Methods System Senmisan oriy Cooling supply Max 45 f9 Type Nore Min 145 Mopar 100m relstive busily x lsomecrdract Mf Daada daina canad T mn during dehumediic ation ot wad cod mode Variable Fan Speed ice capacity control System Simulation only bleating supply Max F Number of tan pend Noe M F Peccert stow thw speed Ty Percent aow at medumspeed T Supply duct bemperatuse fo Humidiliceton Mirana 100m relative haredty CDS PRMOO1 EN TRACE 700 User s Manual System Design Options Cold air distribution 4 77 W Create Systems Fan Overrides 3 Specify the type static apg pressure and schedule for each fan in the system in this case the primary secondary and exhaust
72. General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes view the schedule click Schedules on the Libraries menu and select Utilization as the Schedule type Here the user should be able to view the schedule and find schedules that more closely follow the actual operation of the building Load Design and Energy m The custom schedules for internal loads have values greater than zero for the heating design day type This tells the program to take credit for the internal loads during the heating design calculation This tends to lead to undersizing of the heating coils and is not common design practice To view the schedule click Schedules on the Libraries menu and select Utilization as the Schedule type Here the user should be able to view the schedule and the Individual day types Load Design and Energy m Ihe lighting type selected has less than 100 percent load to space which will cause a portion of the lighting load to go to the plenum Make sure that all rooms using this lighting type have a plenum If some rooms do not have a plenum then select one of the 100 percent load to space lights Load Design and Energy E Click Internal and Airflow Loads on the Libraries menu and select Miscellaneous Loads as the Library type The custom miscellaneous load has zero percent load to space and zero percent load to plenum Because zero percent of the load is seen in the building no heat gain will be applied to the
73. Heating plant 1 bode Doo Wate Doder Electnc Garfred H Gosteed bols Nen Hio Par pounce he restance hea las Heating plant 2 dedicated 04 un exchanger fee Gooteed heat exchanger ATU i mi ia 2 TE t2 For cooling use water source hea As cooled Cookery Pumps Thermal mdoa koat onge pump and air cooled unitary For heating use boiler for the WS system and gas fired heat To asson equemeni diag the deserd equement cateo exchanger las Cooking plart 1 iche ploni E Man Cooling Coa Iles Heating plant 1 boder G Options Vertiaion Cooling Cod Bas Cooling plant 2 dedicated DA un _New Sateen Heating Spstem Fan Cod and DOA ilas Heating plant 2 dedicated DA ure Now Cool Plant Bf Man Heating Cot E Optional Vertiation Heating Cod New Hoot Plori Before Ehli Coira plant 1 chiller planit BEHEE Coira Suttem Fan Code ard DA E Mar Costing Ca mia Meeting plant 1 biss BOE Heating Saeni Fan Code and DOAL Bf Mar Heating Col mi Cbig plane 2 dedicated 014 uni BHEE Cooling Suta Fan Code ard DAL E Optia Vertiation Coaing Cod mia Meeting plan 2 deciceted DA unt BOE Heating Saeni Fan Code and DOAL E Optenal venison Heating Cod Table 4 9 Equipment types Cooling Equipment tab Heating Equipment tab Watersource heat 3 stage centrifugal gas fired hot water pump chiller boiler split system RAUC 20 ton scroll Air cooled unitary rooftop gas heat TRACE
74. Indoor Air Quality Performance TRACE 700 conducts the ASHRAE 62 1 2007 calculation per user defined rates and effectiveness values The ASHRAE Std 62 1 2004 2007 report details calculation results aiding the user In their efforts to optimize the design 6 108 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Modeling for LEED Indoor Environmental Quality credit 2 EQc2 Increased Ventilation TRACE 700 allows users to define the outdoor air ventilation rates for the ASHRAE 62 1 calculation By manually increasing the ASHRAE 62 1 outdoor air ventilation rate 30 showing compliance with this credit is simplified Indoor Environmental Quality credit 8 1 EQc8 1 Daylighting amp Views Credits are awarded when a specified level of daylighting is achieved When users create daylighting definitions within TRACE the program generates a special report showing the footcandles of daylight present in the spaces with daylighting controls CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 109 Modeling for LEED Quick building inputs via the New File Wizard 1 Start by opening TRACE 700 clicking New on the File menu and clicking New File Wizard 2 Enter a name for the project and click Open 3 Select the type of building to be modeled and click Next 4 Select the shape of building to be modeled input the orientation of the building and click Next The Ne
75. Pesuts 06 11 2003 0325AM 06 11 2003 0925 4M 4 r a pa r Note Templates are used to edit the room inputs quickly and to make changes globally rather than on a room by room basis Note You can check the room level inputs in the Create Rooms section if desired Note After editing the templates the remaining sections of TRACE 700 can be input similar to a standard file Brief instructions for how to input the airside systems and assign the rooms to the airside systems are included in the remaining steps for this section Quick building inputs via the New File Wizard TRACE 700 User s Manual e CDS PRM001 EN 9 Click Create Systems Sean ney Reems r a ened ogee te aman name the system and Jeo SOR Re eckete STR TRANE select the appropriate airside system Sytem descipton yin 0 Q Z Variable ha Phat X0 Min Flo Delat On the Options tab input a make up air unit an economizer and an evaporative cooling and or heat recovery device if appropriate B create Systems Fan Overrides System description T Vaaia Volume Reheat 30 Min Flow Delak Fan cycling schedule no lan cycing 100n the Fans tab input the Fan Types and the Static Pressures to account for fan heat pick up and fan energy for all of the fans that exist in the building Click Close 11Click Assign Rooms to Systems and drag and drop all of the rooms to the airside system s created in the last section Fi
76. Sched eamospm te 5 Select the exhaust side secon Stage Altos Energy Recowenp Transter Stage ZAHAR Eneogy Recover T ranater deck for the device In aS eere n ereer S this case Ventilation Supside deck Verion dowranean x Supeide deck Versducon upaveu 9 Extrade dack Vertision upsbeam Exbrtide deck ream will upst ea be Schede Povedable 100 z Schodde Avaksbie 100 selected as the exhaust a l side deck The coil loop m Select Return outdoor air upstream if the mixed air stream recirculated return air after room exhaust and system exhaust plus the ventilation is used as the exhaust side m Select Ventilation upstream if the outdoor air before it enters the make up air dedicated ventilation unit is going to be used as the exhaust side This selection should only be used in combination with a make up air unit In this case Ventilation upstream will be selected as the exhaust side deck The coil loop will be used to precool the ventilation air upstream of the optional ventilation cooling coil Note If the proper airstreams are not selected for supply side and exhaust side decks of the energy recovery transfer device then the unit will not function correctly or may not function at all will be used to precool the ventilation air upstream of the optional ventilation cooling coil Note If both stage 1 and stage 2 energy recovery transfer devices are given the same exhaust side deck then stage 1
77. System Control Strategies Daylighting s Daryigh ling Parameters General Dying Contols Fionan Parameter Claes Parameters intemal Shade Parameters Tenite Na Sagi Em ce Cete imee Rename orini Prevent of Space Adtected 1000 i ad Lighting Selpr 50 0 a Pl Lighting Contl Type Corru G Full Load Poa i Minimum Paree Percent Sin Fe x sd we Minimum Light Percent 0 4 E a j Ming e Light Contec Sepa E Erer I l Light Conte Probably 3 0 He ai a im SWGTRaT Ligii Percent Geomety Referens Heaght A E Danen om Ses 00 k Winches Sill Hep C 00 amp Glass Lergh From 0 au Glass Heye Distance From EA wu Horizoraal Gitte ao tt Shyight Lengthy Distance to Shpkght width Dintance ga Elles cookie meibcalet thoes aleli wal ba uiiscakoulabad d bali blank on nan a The Percent of Space Affected represents the fraction of the space floor area for which the lights are controlled by the specified daylighting controls b The Lighting Setpoint represents the design lighting level in the space in footcandles c The Lighting Control Type is the type of daylighting control being used in the template continuous or stepped Depending on the Lighting Control Type selected either input the Minimum Power and Lighting Percent or the Light Control Steps to simulate how the selected controls will operate d The Light Control Probability is the probability that manually controlled stepped
78. Syster Level Vertiianon O vender cate room F Use syrom det fe Aiton Sum of room nominal vertilator r Feed sotun Outedde on Rani snare aoid a DD Schedde Avsiabie 100 7 dampers Supply a ON cooling high a otide of OD lt The shoud reptesert the corntaned reantance of the carpet fi d ements and the rased floor pane ard shod NOT wmchucde ary on fim neietarce There controls are ignored unless the sudkery cig o hig cod capacity overides we defined on the Creste Systems Heating Cod Owenkdes screen Alemative 1 System description Cred Beam Fan cycling schedule Cyc wth ocrigianey TRACE 700 User s Manual e CDS PRM001 EN 7 Use water cooled chiller and boiler to begin defining the cooling and heating plants for the air handler Rename the cooling plant to Air Handler and heating plant to Air Handler Heat 8 Use the water cooled chiller and boiler to begin defining the cooling and heating plants for the air handler Rename the cooling plant to Chilled Beam and heating plant to Radiant Floor Note Two chiller plants and two heating plants were created his models a dedicated chiller arrangement One chiller provides chilled water to the chilled beams while the other chiller provides chilled water to the main cooling coil in the primary air handler One boiler provides water to the main and pre heat coils found in the primary air handler The other boiler provides water for the rad
79. Unloading Curves i Wether general equipment category in The Equipment Type is the specific piece of equipment in this case 2 Stage Cent w Heat Rec 105 HW Clicking here will allow the user to view all of the specific pieces of equipment available for use this case a Water cooled chiller Clicking here will allow the user to see the different general categories of equipment available w Library Template Editors PFOVYO ste W oerivy se asa comza meaw E Cooting Equipment Main 1 me fF gt 190 tone wath has covery 105 deg He Eqif1it a 2 iw Fima rod wa OOOO EO Crt vd cha oak purp Condenser waia OOOO SEO Cra vol cnd wale paar Heal ince of aux Condenaet Nore The Cooling type is the type of Ores f 1011L compressor used by the equipment an shown here as Centrifugal Clicking M m here will allow the user to view the different types of compressors available lin TRACE 700 ar TRACE 700 User s Manual e CDS PRMO01 EN Creating equipment and unloading curves 3 Select the Cooling category as Water cooled chiller Name the new piece of equipment by deleting the default oooO MUSS Coments compressor energy at Equipment type and fd aa design conditions Cocingipe Hean entering a new name Helical Rotary Chiller Practice Note Avoid using any punctuation in the name Select the Cooling type as Helical rotary w Library Template Ed
80. Verity supply air temperatures accuracy m Verity airflow values Energy values mismatch Verity design loads match Verify equipment efficiencies Verify proper setup and sequencing Verify unloading curves CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 85 Modeling for LEED m Verity schedules m Verity fan coil schedules Economic mismatch Verity design loads Verify energy values Verity defined utility rate Verify any other economic parameters defined Baseline building Once the proposed building has been modeled correctly create a second alternative based on the first This second alternative will be changed to represent the baseline building For information on creating an alternative refer to Creating alternatives on page 6 131 Prior to entering data for this alternative refer to Table G3 1 from Appendix G of ASHRAE Standard 90 1 2007 to determine what changes need to be made Table G3 1 provides a guide for how the second alternative will be adjusted to create the baseline building Remember the mandatory requirements from ASHRAE 90 1 2007 apply to the baseline model as well Additionally refer to the LEED Reference Guide to better understand additional baseline requirements not defined by ASHRAE 90 1 e g process loads Note Generally details not specifically addressed by ASHRAE 90 1 2007 will be identical between the proposed and baseline alternatives Using the pr
81. a DX unit using TRACE 700 output 3 These results will need to be input into the selection program In this case the Trane selection software TOPSS will be used 4 While inputting the results from TRACE 700 TOPSS will give warning and error messages if appropriate In this case when inputting the maximum supply airflow for the unit an error message is displayed stating that the maximum airflow for the 40 ton unit has been exceeded 5 Go to the Temp Humidity tab of Create Systems and input a more reasonable Cooling Supply Air Temperature Maximum and Minimum For this example use 57 F maximum and 54 F minimum Note If the user already knows what supply air temperature or range of temperatures the unit should use this step can be done before the initial calculation However this can lead to over undersizing of the coil s and humidity issues Please refer to Oversizing and undersizing on page 6 51 and Frequently asked questions on page 6 20 for additional information related to the ramifications of inputting temperatures 6 70 3 rane Official Product Selection System Job Workspace JobO1 Input View l a 1 Note When using a selection program it is often easy to over specify the unit TOPSS changes the colors of required inputs to red optional inputs to blue and all other inputs to white ia Main Cooling Main Heating Motce Elecinical General UI Detned Al Fields
82. adjacent room ipace Application considerations m The cool temperatures in the underfloor plenum increase System Design Options Underfloor air distribution conduction and radiation in the space As a result the conductive resistance of the floor must be considered When modeling multiple floors an adjacent floor should be modeled as the surface separating the return air plenum of the lower space and the supply air plenum of the adjacent upper space TRACE 700 User s Manual e CDS PRMOO1 EN m Because the supply air is introduced from the pressurized floor plenum a warmer supply air temperature is necessary to avoid an uncomfortable temperature difference between ankle and head heights As the room sensible cooling load decreases the capacity of the main cooling coil will be reduced resulting in a warmer supply air temperature m While the supply air is delivered at warmer dry bulb temperatures It still must be delivered dry enough to provide sufficient dehumidification Thus air leaving the cooling coil should be about the same temperature as in a traditional system which drives the need for the return air bypass Related reading m Underfloor Air Distribution Turning Air Distribution Upside Down Engineers Newsletter volume 30 number 4 Sample scenario A UFAD system is to be installed in a two story office building To model this system each floor requires a floor plenum and a ceiling plenum Calculations will h
83. allows the system to operate in either the cooling mode or heating mode Using a heat recovery system allows some zones to operate in the cooling mode at the same time other zones operate In the heating mode Figure 3 22 Variable refrigerant flow system indoor units outdoor unit Application considerations m The indoor units are modeled with multi speed fans The VAV Minimum controls on the Airflows template or Airflows tab of Create Systems can be used to define the supply airflow when CDS PRMOO1 EN TRACE 700 User s Manual Cooling and Heating Plants 3 81 Variable refrigerant flow system To model the VRF system begin by defining the air distribution system 1 Pick Variable Refrigerant Volume as the system type Click Apply to save your entries 3 82 Cooling and Heating Plants the space temperature is within the thermostat deadband The default is 10 of design supply airflow If a VRF Heat Pump outdoor unit is selected the zones served by that unit will either all operate in the cooling mode or all operate in the heating mode If a VRF Heat Recovery outdoor unit is selected some zones served by that unit can operate in the cooling mode while others operate in the heating mode In some applications the Indoor units may be able to handle a portion of the outdoor air load however a separate dedicated outdoorair system is often required See Dedicated outdoorair systems on page 4 45 for m
84. any heat given off by people in the space and to neglect ventilation for the space if the ventilation was entered as cfm person Load Design and Energy The Cooling Only Design schedule is selected for any of the internal loads This schedule should only be used for design calculations not for energy analysis It simulates 100 percent of the internal loads in the building 24 hours a day except during the heating design portion of the calculation which may not be what is actually occurring in the building This tends to lead to an overestimation of cooling energy and an underestimation of heating energy To view the schedule click Schedules on the Libraries menu and select Utilization as the Schedule type Here the user should be able to view the schedule and find schedules that more closely follow the actual operation of the building Energy Only The internal loads are scheduled as Available 100 This schedule typically should not be used for internal loads It simulates 100 percent of the internal loads in the building 24 hours a day which may not be what Is actually occurring In the building In addition it also tells the program to take credit for the internal loads during the heating design calculation This tends to lead to an overestimation of cooling energy an underestimation of heating energy and undersizing of the heating coils because the internal loads are meeting all or most of the heating loads To Advanced Usage and
85. be viewed on the Description list The individual Defined rates also known as definitions can be found below the comments section of the rate structure To create a custom rate structure click New Structure A new Rate Structure library window will open with a default rate structure name in the Description field In the Description field delete the default rate structure name and enter a name of your choice Avoid using any punctuation in the name Click New Definition to start defining the rate structure Select the utility that you would like to define first In this case start with Electric consumption Next select the Rate type On peak Off peak and so on In this case start with On peak Define the remaining parameters as necessary w Library Template Editors Pile Yaw Options window Hap P CvTEax te 222 i 47 nsFf Oee i Rate Defintion Oerenghon Noth Tene of Day 2 Utility Elect concumeme Mirwnuzs chupe f Shut penod inaw Defined cates Erd pened Deventer Rasse forced a Mrana demand Fuel adhattmert foo Customer Change 14 KWIVEW Hag Na Aate schedule AkWh Da Detain at a Rate structures are used to tell the program what the utility company s charge for electricity water gas and so on The definitions tell the program what values to use during the different parts of the economic calculations TRACE 700 will not calculate co
86. because the liquid desiccant system will try to maintain the ERD energy recovery device leaving air humidity ratio at its design value This is auto calculated based on the design conditions unless overridden by the user on the Desiccant Dehumidification Options screen that appears when the Options button is clicked Note For instructions on how to create custom schedules refer to Creating schedules on page 6 137 Within the custom schedule 0 percent would indicate that the desiccant device is deactivated and 100 percent would indicate that it is available to operate Ahemative 1 Syitem description Syitem ool Indrect col schedule E s 065 Note If both stage 1 and stage 2 energy recovery Stage Aptos Energy Recowerp Trancter Type Socks dasi on vent deck Sup tde deck Verran upiTream transfer devices are given Extraide dack Syrom exhort 5 the same exhaust side deck ee then stage 7 will be upstream of stage 2 aveatie 100 F Mec tovewsss Opor 4 6 System Design Options TRACE 700 User s Manual e CDS PRM0O01 EN Desiccant dehumidification lz Next define the heating plant that serves the airside heating loads 8 Add a gas fired hot water boiler to serve the main heating load To provide the heat needed to regenerate the desiccant add a gas fired heat exchanger Not shown Specify equipment types capacities schedules and the full load consumption of the hot wat
87. calculation only model to a load energy and economic analysis model The actual inputting of the plants and economics will not be covered Only changes and or new inputs in the Create Rooms and Create Systems sections will be covered Rooms tab of Create Rooms Room area inputs Check to determine if large areas with exterior exposures 10 000 ft2 are being modeled as a single space An example of this would be a one room input for an entire floor of a building This will lead to the internal loads negating the envelope losses and an underestimation of the design loads and energy consumption Refer to Modeling large rooms and zones on page 6 45 for a detailed explanation To correct this issue use at least 5 rooms per building floor or wing 4 perimeter and one Interior space The New File Wizard can be used to accomplish this with minimal effort Refer to Quick building inputs via the New File Wizard on page 6 110 for additional information Thermostat inputs In the load design calculations TRACE 700 only requires inputs for the occupied cooling and heating setpoints In energy analysis TRACE 700 will need to know if these setpoints are constant or if a control strategy that uses night setback or driftooints will be used The default values for the thermostat driftooints are 90 F and 55 F respectively This means that whenever there are 5 percent or less of the people in the space determined from the people schedule
88. controls are utilized Note Under the Geometry section input the Reference Height A of the daylight sensor All other values under the Geometry section will be auto calculated if not input Multiple templates can be created and used in the same file and even in the same space TRACE 700 User s Manual e CDS PRM001 EN z Dievhigliting Pana bers x General Davighting Contos Poon Fima Glatt Parsreters intemal Shade Parameters 6 Click the Room mA Parameters tab to select the Alternative the Daylighting Schedule the Daylighting Reference Points and the Perimeter Depth ra Araidh IW e 7 For this Daylighting piapa schedule choose Available 100 and click Yes to apply this schedule to all rooms a The Daylighting Schedule acts as an on off switch Utilization percent hours gt 1 percent means the daylighting controls are available while utilization percent hours 0 means the daylighting controls are deactivated and no daylight reduction of lighting energy is allowed that hour Typically the schedule will be available 100 percent off O percent or a custom schedule that neglects daylighting during design but applies it during energy analysis for details on creating schedules refer to Create schedules on page 2 19 b The Daylighting Reference Points are used to select the templates created on the Daylighting Controls tab Up to two Daylighting Reference Points are allowed per space c The Perime
89. database that contains common design parameters for load calculations attributes for common types of HVAC systems and data provided by the manufacturer for specific equipment alls A TRACE 700 can simulate more than 30 different types of air distribution systems You can combine these systems in various ways to accommodate the unique application needs of the building you are studying 2 4 Program Overview Calculation phases A brief description of each calculation phase follows Phase 1 Load design Calculations performed during the load design phase define building cooling and heating loads at design conditions by hour and by system zone and space as well as total for the building from information found in the Weather library for the city you identify The calculations account for coincident loading by applying the schedules you define for items such as lights occupancy and miscellaneous loads Beyond this the program accounts for energy consumed by systems that do not contribute loads to the airconditioning system Energy consumption of this type affects both the overall energy demand of the building and the associated energy costs For TRACE 700 to perform these calculations you must first describe the construction orientation and location of the building as well as its utilization profile schedules for lights occupancy and miscellaneous loads Other required entries include the type of airhan
90. displayed by clicking Alternative 3 and then clicking Enter Project Information 6 134 Advanced Usage and General Modeling Tips Creating alternatives Sample scenario 2 In this second scenario a glass comparison between Alternative 1 and Alternative 3 the third alternative will only require a change to the Templates section In this case the third alternative will be copied from Alternative 1 The illustrations that follow demonstrate how to create a new alternative by copying an existing alternative Step 1 naming the new alternative Step 2 and editing the appropriate sections of the new alternative Steps 3 and 4 ee IRALE MM CACOS TRACE TIM Popes Tutorial ine n File Edi Atera View pis Lissie Template Aleme Beiu Window Help eBo t Rete Fete ae SEE AF Project Navigator Upe Albermative 1 2 Apa O Reeves 2 ene D Tita 2 Abiged eiii O Abmgred Aiii 2 Pll 0 Plaeds Syiria Atego Sgedom fags Ho uiy rates defined Ho udb aei dard sk Ov at au Goh a P DE a Oot oe FA Poet Q H Naming the new alternative is not a me ll required step but naming the Bulking Eo alternatives makes the file easier to Coren i use and or edit In this example Comments Alternative 3 has been named Glass Study TRACE 700 User s Manual e CDS PRMO01 EN 3 Right click any section of Alternative 3 On the list that appears click the section to be edited for this example click Template
91. documentation TRACE 700 CD ROM Feedback form TRACE 700 User s Manual Getting Started Manual Output Interpretation Other PDF manuals The TRACE 700 CD ROM contains everything you need to install and run the TRACE 700 application For information about the software and hardware needed to use TRACE 700 refer to the ReadMe file on the CD ROM Installing TRACE 700 The TRACE 700 program must be installed on and run from your hard disk or the network hard disk you cannot run the program from the CD ROM Installation instructions are available in the ReadMe file on the CD ROM Uninstalling the program If you ever need to remove the TRACE 700 application from your PC use Add Remove Programs in the Windows Control Panel This command removes all TRACE 700 components except for files shared by other applications Note If you customized any of the TRACE 700 libraries be sure to export them before uninstalling the program Consult online Help F1 for instructions Starting TRACE 700 Start the TRACE 700 program just as you would any software application Do one of the following TRACE 700 User s Manual e CDS PRMOO1 EN m Double click 2 on the desktop E From the Start menu select Program Files gt C D S Applications gt TRACE 700 gt TRACE 700 Note The above sequence is correct only if TRACE 700 is installed to the default folder Learning TRACE 700 Trane provides a variety of options to help you learn TRACE 7
92. e CDS PRM001 EN Direct and indirect evaporative cooling A third option blends both direct and indirect evaporative processes Staged evaporative cooling systems Inset C are arranged so that the indirect coil activates first precooling the supply air without increasing the moisture content The supply air then passes through the direct evaporative coil where it Is cooled further with only a slight increase in humidity A conventional cooling coil if used provides the additional cooling needed to satisfy any remaining load Application considerations m Although evaporative cooling can effectively reduce the amount of mechanical cooling an application requires it seldom eliminates the need for a conventional cooling coil altogether m Using evaporative coils in conjunction with a conventional cooling coil typically adds trom 0 2 in wg to 0 4 In wg to the static pressure of the airdistribution system m Direct evaporative cooling systems require additional care to ensure proper cleanliness and operation Sample scenario The airhandling system for a building includes three cooling coils illustrated in Figure 4 14 on page 4 40 Inset C and an economizer that modulates based on the ambient dry bulb temperature If the economizer is unable to satisfy the cooling load or if ambient conditions preclude economizer operation then the indirect evaporative cooling coil 60 percent effective activates If the cooling demand still is n
93. each unassigned room to the desired gzone or system od Fan ods Hal atorage Tekee Haami 3 Total iaa G ig M Est Aike 6000 cim Est Load 15 00 tong When selected the Summary Information check box displays the estimated airflow and load as well as the total area for the selected rooms Initially these estimates are based on common industry rules of thumb 1 cfm ft2 and 400 ft2 ton You can assign individual rooms to a system If you are modeling a VAV system consider grouping the rooms served by the same VAV terminal as a zone Then assign the zone to a system This practice permits the program to calculate the design airflow for the heating coil within the VAV terminal as well as the design airflow for each room in the zone Note Refer to Zoning of rooms on page 6 47 for details on zoning Create plants Cooling and heating plants represent mechanical equipment that consumes energy to treat air throughout the building As shown Program Overview 2 15 Performing basic tasks Figure 2 12 Create plants Project Tree View Tween E Cision 102 al Egpaar concen Equement catego a E Classroom 103 man E Cisssroom 104 E Room 100 Administration BE Room 110 Tech Shop ED Room 111 Munie Room BB Caterers i Create Plants E Gymnmnim a BB Classroom 125 Atemana lod FPvay Amuoa O Fan Colt Halt Stoeage La
94. establish the target water temperature for the tower sump CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 57 Cooling tower with VFD Create a cooling plant consisting of a watercooled chiller cooling tower and pumps 1 Describe the chiller as a three stage centrifugal 2 If desired specify the cooling capacity required if the plant contains more than one piece of cooling equipment 3 To include the pumps in the calculation of plant energy consumption complete the entries for full load consumption 4 Pick a cooling tower equipped with a VFD To view the unloading characteristics of the cooling tower or to create a tower with a different unloading curve and add it to the TRACE 700 library of heat rejection equipment use the Library Template Editors program 3 58 Cooling and Heating Plants Cooling tower with VFD Related reading Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN Tower Water Temperature Control it How Engineers Newsletter volume 24 number 1 Sample scenario A chiller plant consists of a three stage electric centrifugal chiller that rejects condenser heat to a cooling tower The capacity of the cooling tower fans is regulated by a variable frequency drive The illustrations that follow demonstrate how to add a centrifugal chiller Steps 1 2 related pumps Step 3 and a cooling tower with variab
95. etc modeling the make up of these components Is critical to ensure accurate results Create templates The thermal zones determined during the planning stage can serve as the space types used to create templates For example one thermal zone may define an office space while another defines conference rooms Use these space types and the libraries developed in the previous step to create templates For more information refer to Using templates on page 6 125 Note Importing a gbXML file generated by a CAD program will create templates automatically based on the zone assignments defined by the CAD programmer TRACE users simply have to update template information upon completion of the import process e g construction types schedules Create rooms The easiest and quickest method to create rooms is to import a gbXML file Refer to gobXML import and export on page 6 181 for detailed information on this feature In the absence of a gbXML file users are required to manually enter spaces Utilizing templates created in the previous step significantly reduces data entry While constructing spaces do not forget wall and glass dimensions room to room air transfers see Balancing airflows on page 6 60 and partitions Note Although not necessarily a strategy used to reduce energy consumption ASHRAE Standard 62 1 2007 is important to the overall health of the building and its occupants TRACE 700 provides users the abi
96. exposed floor Con Deina x with an Adjacent Room external temperature Exponed Slab on grade Method rchecmnt Foam method Select Room 101 ona 12 LW Cone z Ceiro F A W e Visie D aef Heraf F as the Adjacent Room Paia Doa oi eure Aai oom Poom 10 Create Systems Selection Ahire Sytem deceit EE FAD WN va Baseboard Heating 4 In Create Systems select UFAD VAV w Baseboard Heating LUnvcafiooe Aa Diintitbutioes SFPA 4 86 System Design Options TRACE 700 User s Manual e CDS PRM001 EN Underfloor air distribution 5 On the Options tab click Advanced Options 6 Define the Supply air path duct location Space sensible gains to occupied layer Underfloor plenum height and Conductive resistance of raised floor Note If Space sensible gains to occupied layer is left blank it will be calculated automatically 7 Define Fans Static Pressure and Full Load Alena 1 yiten deicipion M UFAD Wav w Baseband Heating Lea j Evaporsiee Cocting i J Bais Supsi Optimum top Dn Lirras pirate reigh i n 6 See a cr Sched thy peii echada ite i j p Feoir Duct itha Loves Panair length Pirati Upitan rimena hoak gga iier i Maian o en irrati Cipari birila beai aior p x as Liming Pini Abay boig Gta hivei by phere fo Selec Manecaingian 7 Resmen SS peepee Type Optional veriiation Ausiieny cooing cod asra Aner Primar Sytem Hone zi Tuppi a DE cooi
97. fans Coltar system X Fan cycing schodue No tan eyeing FC wAVFO Crt Zone Peset FC Certrfugal const vol Typically the secondary fan is a central heating fan However in a fan powered VAV system it represents the fans in the VAV terminals ll When defining the Seres Fan Powered VAY Avaliable 100 Avelabie 100 Avalsbie 100 Avalsble 100 Ah coolin lant Cooling glare Coolers piane 1 Heat rejection ype E5100 Cocina tower ssc oa a_i wf ema 4 Increase the full load Ecamoment category Watercooled crates T Thamal siceaga tohen Eqpmertipe 3519s Core sst S S id Twe Noe iY N energy tate Olas CAIME z O O OON i cas to reflect the additional lift e aa A required from the re compressor Use a computerized selection program to determine the new energy rate Corfiguston Cooling Equipment Heng Eaim Bore Utity Mipc Accesso If left blank in a single chiller plant TRACE 700 sets the capacity of the chiller equal to the design load of the airside systems and or coils assigned to it The capacity should not be left blank in a multiple chiller plant Note Some cold air systems deliver 45 F air to fan powered VAV terminals where it is warmed to 55 F by mixing it with plenum air This technique increases the energy consumed by the secondary fans in the VAV terminals To model the effect on the secondary fans either enter the new full load energy ra
98. for the building Click Equipment on the Libraries menu then click Misc Accessories he unloading curve full load energy rate and so forth of the simulated pump can be viewed If the actual and simulated pumps are not similar then a custom pump will need to be created m f multiple pumps are going to be used to distribute the chilled water then either a single pump with a combined unloading curve assigned directly to the cooling plant or multiple pumps assigned to the cooling plant as miscellaneous accessories via the Misc Accessory tab should be used Related reading E Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN m An idea for chilled water plants whose time has come Variable primary flow systems Engineers Newsletter volume 28 number 3 m Variable primary flow systems revisited Engineers Newsletter volume 31 number 4 Sample scenario In this example two chillers in a parallel arrangement with a single VPF pump will be modeled Note There are actually two types of variable primary flow arrangements dedicated and manifold This scenario is manifold A dedicated arrangement would have a variable pump for each chiller rather than one variable pump for all chillers 3 14 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Variable primary flow chiller arrangement llain Create Plants define the cooling plant
99. heat pump BHEE Coding Suntan WSHF Bar Costing Ca Te Backus beer Cooling and Heating Plants VWatersource heat pump system as a backup if the heat pumps 3 71 Ground source heat pump system A common variation of the watersource heat pump system uses the earth as both a heat source and a heat sink Known as a ground source GSHP system this variation takes advantage of the relatively constant 45 F to 65 F temperatures that exist 20 to 30 feet below the surface When buried in the ground the high density thermal plastic pipe acts as a heat exchanger During the cooling season it transfers the heat absorbed by the heat pumps to the ground for storage When heating is needed the heat exchanger recaptures the heat from the ground and returns it to the building Figure 3 19 Applied ground source heat pump system other ground level A 6 ft to additional grids 1004200 ft Temperatures at this depth typically range from 45 F to 65 F If properly designed an applied GSHP system does not require a cooling tower Aesthetically this means that all of the heat from the building can be rejected without any visible sign of a cooling system A boiler is also unnecessary if the heat pumps can satisfy the entire heating load which saves initial cost and floor Space 3 72 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Ground source heat pump system Application considerations m GSHP systems are
100. i stage Amb Mod C pog Capscty Ln LT E Cooing Equipment Main Coding category Water cooind chier 7 Ecpicmantiype HelcalRctuy Chae Pcie Coxknghpe ecaa Yd Frei Rate Canacdu Refer to point 4 of Additional Items for custom ambient relief curve Prmay Seconday Curve type Power communad fe Hebcal Rotary Practce fwe Heboal Potary Practice Standen 12 Ambient modiicetion 01500 Amb Mod J r Doe Croscty instructions on creating a Note For heat recovery chillers select None for the Secondary Ambient modification curve The tower or condenser fan is normally bypassed during heat recovery mode in order to maintain the highest possible leaving condenser temperature CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 147 Creating equipment and unloading curves ST editors lox 14Click the Options tab to Pha aw Opiera Window Help OTR Se eee lTEE4 TOMS AD SEP TRANE further define the equipment Free cooling type Fuel type Water Odlerence fio F temperatures Dewgnerteing 5 F Accessories and so on Mirimumn opeesting 5 F can be defined on the ooo DI Options tab For this r Fasa Cooking example ensure that E Utility is selected as the Free cooling ping one Fuel source and Electric Rees P WwW J is selected as the Fuel Plate ond hame hoat exchanges approach TF type 15Enter the Chilled water temp Design leaving
101. in response to the thermostats The schedules for internal loads ventilation fan cycling and so on are the proper place to adjust the loads seen by the coils Energy Only Zoning alo x GS West Office m Multiple rooms are assigned directly to a Single Zone System Refer to Zoning of rooms on page 6 47 for instructions on proper zoning of single zone systems and for details on how zoning affects this system and other system types Load Design and Energy m Only thermally similar rooms should be zoned together It thermally dissimilar rooms are zoned together oversizing and poor space temperature control will typically occur Load Design and Energy CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 15 Common modeling mistakes 6 16 Cooling Equipment and Heating Equipment tabs of Create Plants Cerna Chiler Plart S U1 Cnst vol chal water pumo EUND Crest vol cred wale penn m For any WSHP system the thermal storage has been removed The thermal storage associated with the WSHP is the water loop Without the water loop the results for the energy consumption of the WHSP compressors will be highly inaccurate Energy Only The Equipment Type has been left at the default value Default Aircooled Chiller Default Boiler and so on For accurate energy analysis the program needs to know the specific type of equipment used in the building Th
102. in this discussion of sensible wheel energy recovery For arrangements other than this one select the appropriate energy recovery configuration similar to step 1 in this example and refer to the following Figure 4 12 m for nset A refer to steps 1 through 6 in Fixed plate heat exchanger on page 4 21 m for nset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 m for nset C refer to steps 1 through 6 in Heat pipe on page 4 27 Figure 4 13 m for nset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 m for nset C refer to steps 2 through 7 in Coil loop for exhaust air energy recovery on page 4 8 Related reading m Airto Air Energy Recovery Engineers Newsletter volume 29 number 5 E Airto Air Energy Recovery in HVAC Systems Applications Engineering Manual Trane literature number SYS APMO003 EN CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 35 Sensible wheel 4 36 1 After defining the WSHP system and the dedicated ventilation system select the desired air to air energy recovery transfer type which determines the type of energy recovery transfer and the basic configuration In this case Sensible wheel parallel SA tempering A message will appear that asks whether the user wants to account for energy recovery transfer during the design and energy analysis simulations or only during th
103. is a way that utility companies penalize the consumer by floating their kWh consumption cutoffs based on the kW demand required that month TRACE 700 will use monthly kW demand to apply to the kWh kW cutoff to determine the monthly kWh consumption cutoffs Therefore the kWh consumption cutoffs will change monthly based on the demand determined by the program Additional Items Time ot use rates are a cross between stepped rates and time of day rates Please refer to Stepped rate on page 6 150 and Time of day rate on page 6 155 for instructions for inputting each individual definition If the rates do not apply yearround definitions can be created on a partial year basis For example if during the summer months the kW is charged differently a separate definition can be created Note Definitions cannot wrap around a year For example September to May would not be a valid input for the Start and End Months January to May and September to December would have to be input as two separate definitions to compliment the definition Advanced Usage and General Modeling Tips Creating utility rates 6 165 E Rate Structure Library Fiate Detain Deptneion Hohe Tint oF Dap Lit ty Elseine demand 7 Commet Example for Additional Item 2 re AA e airs Ur f d res Deore b bati charra DN gamak Jiris arii Leck coniungi Di pea January Decent 3 Select Reduced year for the Time of Day
104. level main and or reheat heating coils the heating coil in the terminal device The terminal reheat system Is very similar to a typical VAV with reheat system except that the airflow for the rooms and from the supply fan is constant Zones should be created for this system if one terminal device will serve multiple rooms All rooms and zones assigned to this system type will be served by the same supply fan and cooling coil For a variable volume at the supply fan and at the terminal devices RTU there are several different airside system types that are typically used Variable Volume Reheat VAV with Baseboard Heating Series Fan Powered VAV and so forth The schematic drawing of the systems in Create Systems can be used to help find the correct system type based on the location CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 25 Frequently asked questions of the heating coils what type of terminal devices will be used and so forth For these system types zones should be created if one terminal device will serve multiple rooms The same supply fan and cooling coil will serve all rooms and zones assigned to these system types For a system with a constant volume fan and variable volume terminal devices also know as a Varilrac system there are three airside system types that are typically used ChangeoverBypass VAV ChangeoverBypass VAV with Local Heat and Changeover Bypass VAV with Reheat The
105. load calculated by TRACE 700 3 The supply airflow under the Cooling Coil Selection portion of the Checksums report is a result of the psychrometric analysis performed by the program The program knows the space load sensible and total to be satisfied at every hour At the time of coll peak in this example month 7 hour 16 the program performs a psychrometric analysis to determine the required airflow and coil leaving temperature to satisfy the space load For a VAV system this coil leaving temperature is fixed The psychrometric analysis uses a least squares fit estimate for a generic coil curve as it iterates to determine return air temperature coil leaving temperature and supply airflow The value of 14 863 cfm in the Airflows section of the report comes from the space peak sensible load which in this example occurs at month 7 hour 17 Q space sensible DSHP x AT space _ 289 209 Btu h 1 081 x 75 F 57 F 14 863 cfm supply airfl OW design As is listed at the top of the Checksums report the system is a variable air volume system Thus the airflow at the time when the load on the coil peaks may be different than the airflow at the 6 72 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Selecting a DX unit using TRACE 700 output time when the space peaks This is the main reason for the discrepancy in Coil Airflow versus Supply Airflow In a nutshell the supply airflow 14 863
106. media or atomized water Using low pressure low temperature water vapor simplifies the humidification process It is also effective complete absorption occurs in a short distance and the sensible air temperature remains constant so higher relative humidities can be achieved without condensate forming in the air handler or ductwork Application considerations m It is important to introduce no more moisture into the air stream than can be absorbed without condensation m Condensate is most likely to form first on windows because the surface temperature on them is usually the coldest in the building during cold weather If the humidity required for a particular application causes condensation on windows add insulative films or extra panes of glass to increase the thermal resistance m A humidifier that is factory installed and controlled as an integral part of a central station air handler is typically more cost effective and less prone to misapplication than an equivalent field built system Relating reading Designing an IAQ Ready Air Handler System Applications Engineering Manual Trane literature number SYS AM 14 Sample scenario The variable volume airdistribution system for the building consists of series fan powered VAV terminals that are equipped with electric heat coils To maintain a minimum relative humidity CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 9 Humidification of 30 percent dur
107. member in any project file Q Can SEER Seasonal Energy Efficiency Ratio be input for energy rates A SEER is a measurement of overall energy efficiency SEER is defined as the total cooling of a central unitary air conditioner in Btus during Its normal annual usage period for cooling divided by the total electric energy input in watt hours during the same period The Seasonal Energy Efficiency Ratio is a standard method of rating air conditioners based on three tests All three tests are run at 80 F inside and 82 F outside The first test is run with humid indoor conditions the second with dry indoor conditions and the third with dry conditions cycling the air conditioner on for 6 minutes and off for 24 minutes In other words the SEER is a combined efficiency calculated from three different conditions Note The published SEER may not represent the actual seasonal energy efficiency of an air conditioner in different climates ARI Standard 210 240 94 provides detailed information about SEER and how it is calculated Refer to the following Web site for more information about ARI Standard 210 240 94 http www ari org std individual 210 240 94 pdf TRACE 700 requires a full load energy rate at design conditions an unloading curve at constant condenser temperature and an ambient relief and or modification curve This data will give the program detailed information about the energy consumed by the equipment under a wide variety of op
108. midnight to midnight 3 Set the midnight to midnight percentage to 0 for Saturday and Sunday indicating that the building is not supplied ventilation during that time End a Jal Month oriasty December 4 Create a new Utilization C Rape Day type Cocing desan m Wenkdyy schedule that defines when tia the night purge cycle occurs that is on from 3 a m to 5 a m Cooling design to Weekday Jarsay December Shaday to Sunday Heaters deny A percentage greater than 0 means that night purge Is available ene s Sename Op 5 Set the Midnight to Midnight percentage to 0 NOTE The rest and lockout are avakabe fr the iodovang Desir chose ev uaton vention reheat miniman ad al system for Saturday and Sunday indicating the night purge is not active on weekends not shown 5 18 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Unoccupied ventilation night purge 6 Establish a lockout that will disable the night purge cycle if the outdoorair temperature is greater than 55 F In either the Create Rooms or the Create Templates section of your TRACE 700 project 7 Switch to the Airflows tab and select the ventilation schedule defined in Steps 1 3 for normal occupancy In this example the When Occupied schedule introduces 100 percent of the design outdoorairflow requirement between 7 a m and 5 p m on weekdays At all other times the outdoorair dampers are clos
109. monthly design 24 hour profiles based on the weather extremes for use with the load design simulation For a more accurate analysis be sure to check the design summer and winter dry bulb temperature and wet bulb temperature and adjust them as necessary before completing the import process Reasonable and accurate design conditions can be obtained from the most recent ASHRAE Handbook of Fundamentals Importing weather files is discussed in Adding weather locations and activating the 8760 calculation methodology on page 6 167 TRACE 700 User s Manual e CDS PRMOO01 EN General modeling hints The hints this section will helo you obtain an accurate analysis of building loads energy consumption and the economic impact of various HVAC designs Use them in conjunction with the specific instructions in Chapter 3 through Chapter 6 to successfully model common system level HVAC options and control Strategies Plants and equipment m When you create a new project the program automatically adds the first cooling plant and the first heating plant for you m fa plant consists of two or more pieces of equipment specify the capacity of each piece of cooling or heating equipment If you omit this information the program assigns the entire load to the first piece of equipment that you added to the plant If you define the capacity of the first piece of equipment but not the second the program will allocate the remaining plant capacity to the
110. more expensive to install but less expensive to operate than conventional watersource heat pump systems Perform a life cycle cost analysis to determine the economic viability for a particular application E Installation requires excavation trenching or boring by a qualified contractor m Ground coupled loops can be installed in a horizontal vertical or spiral configuration Available land soil conditions and excavation costs will determine the appropriate choice for a given application Note A boiler will still need to be input for a GSHP model in TRACE 700 However if the water loop is properly sized input as the thermal storage capacity the minimum and maximum condenser operating temperatures are correct and the load profile is realistic the boiler may not activate Related reading E WaterSource Heat Pump Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRCO15 EN Sample scenario An applied ground source heat pump system one heat pump per room provides comfort cooling and heating for a multistory commercial building The pump that circulates water through the common condenser loop is rated for 50 feet of static head A gas fired boiler and an auxiliary pump rated for 20 feet of static head serve as a backup if the condenser loop is unable to satisfy the entire heating load Note TRACE 700 generates a special report Thermal Storage for HVAC designs that include thermal sto
111. new ones of your own Because schedules are key to developing accurate system models the procedure to create a schedule is summarized here for your convenience Although the example specifically describes a Utilization schedule other types of schedules are created in similar fashion Table 2 1 Example schedule for year round building occupancy Day Begin End Design Occupancy Monday Friday midnight 7 00 a m 0 unoccupied 7 00 a m 8 00 a m 20 8 00 a m noon 100 noon 1 00 p m 50 1 00 p m 5 00 p m 100 5 00 p m 6 00 p m 20 6 00 p m midnight 0 unoccupied Saturday Sunday midnight midnight 0 unoccupied 2 20 Program Overview Performing basic tasks TRACE 700 User s Manual e CDS PRM001 EN Sample scenario Table 2 1 on page 2 20 describes the year round schedule for the occupancy of a building Use this information to create a new Utilization schedule in the TRACE 700 Schedules library Also keep the following points in mind whenever you apply or customize a schedule m When performing a reduced year simulation each schedule must include individual definitions for each of four day types Cooling design Weekday Saturday and Sunday For more information refer to Simulation methods on this page se 2 To make the schedule available for calculations of the design cooling load select Cooling design as the starting day type To identify a separate schedule for weekends select
112. of these towers to add your own cooling tower definitions to the library of Heat Rejection equipment Cooley chart Equpmert tog Equipment catego waar cosed cras x Egapen ype E Coning pilare 001 Heat rejection fwater cooked chiller 001 7 Tye Optimized VFD CAower 10 Range x Hourly ambient wet bulb offset Thamal storage Piney ci pia EEE wastes parm Conders reat A Cnet vol ond water pump low speed ate ener IE Percent KA ood m Design Charactesstics Trepecatuem Aggrosch i Range F Wet bub Desinwater 3 famton x Makap mate 32 omore Mouty ambient WE ottset F CDS PRMOO1 EN TRACE 700 User s Manual Urinsding curve EIS Matey Tower wVFD Ealse Malay Tower wiV FD of Full Power 10 gt bad 19 7 kad of Full Losd o wo r Assignment of Coll Losds F Man I Dect evapceative V Amiay F Mise cooing koad Cooling and Heating Plants Chiller tower optimization FF indirect evaporative FF Optional venation Sie im __ cor Dette 3 61 Domestic hot water assigned to a boiler Current construction practices yield well insulated tightly constructed buildings that lose less heat and experience less infiltration than their predecessors The reduced heating burden permits the use of domestic hot water for comfort heating A central boiler not only provides potable hot water for washing and cooking but also for comfort heating that is b
113. on a room by room basis the room will be allowed to drift up to 90 F or down to 55 F before the equipment turns back on If the building control system is not going to allow the room setpoints to setback this far the values need to be overridden If the user would prefer to have TRACE 700 change the room setpoints based on the hour of the day the Thermostat schedules can be used Typically users need to create their own Thermostat schedules CSTAT and 6 170 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Altering a load design file for energy analysis HSTAT should never be used for the Thermostat schedules They are intended to show the flexibility of the Thermostat schedules Note The schedules override the setpoint and drift point entries for energy analysis calculation and inputting unrealistic driftooints or creating unrealistic Thermostat schedules can lead to an underestimation of cooling and heating energy Also the cooling and heating setpoints should typically not be input as the same value Thermostat setpoints should have at least a degree of separation to model the drift in the thermostat Not correcting this input will result in cycling of the cooling and heating equipment and possibly an overestimation of the energy used by the equipment Internal Load tab of Create Rooms Internal load schedules Ensure that the Cooling Only Design schedule is not selected for the internal load
114. or occupancies 6 Asummary of the data input to this point will appear Click OK 7 Click OK to start entering economic information 8 Input the desired economic information Start by inputting all appropriate costs maintenance installed cost and so on Then either click Libraries to create a custom utility rate or select a custom utility rate that was previously created 9 When completed click Apply click Close and then click OK CDS PRMOO0O1 EN TRACE 700 User s Manual BRACE Chiller Plant Analyzer Weather Witand Step 2 mee a TRACE Uhlir Plant Aunalyeer Wizand Ste dhe valh ere Gro ny SOT Guage rath banoni theater nag economies Spid busking preatile paak z they 5 lene tei Cedar E f celal urii idy wah oor ew hes ee ea eee ee z Hema Mtn Them i an enthalpy based aizida economizer bring uned in this hin m Brei on ther petank thes pofle can aha ber uted ior other places with 5 Q A TRACE Chiller Plant Araho file wat crauted uiing peee aiea math tieram ar buking brii wahi Hd bens of cooing j PRO Ib df Paitin 5 Parallel i Shiller plant conky aion 6 ee iD Dahe yam baana Afaan Fier birna 1 Abemstive 1 Equement installed cost P700 fs Revenue pensly fo s z Cmo Youl mantenance epense 0 ston Dukino wea overide 100 ai Addins frst cont o0 fs z Bu drg copeciy ovenide 350 wa r Utility Rate Company Nor
115. or rebates Many utility companies face a capacity shortage for a relatively short period each day typically during normal working hours To encourage users to reduce their energy consumption the local utility often imposes time ot day rates that are highest during peak demand periods One way to curtail the energy costs incurred at these higher rates is to operate the cooling equipment when utility rates are low usually during the evening and store the thermal energy potential until it is needed Ice tanks like those shown in Figure 3 5 are often used as a means of thermal storage because of their compact size and pre engineered design During off peak periods when utility rates are low the chiller cools a glycol water mixture to a temperature of 23 F This mixture then circulates through tubes within the ice tank where it freezes the surrounding water When cooling is needed during an on peak period when utility rates are high the glycol water mixture heated by the building load circulates through the storage tanks to melt the ice Figure 3 5 Example of a chilled water loop with thermal energy storage glycol water pump bypass blending valve valve watercooled chiller CDS PRMOO1 EN TRACE 700 User s Manual Cooling and Heating Plants 3 21 Thermal energy storage Application considerations m The tanks required for thermal energy storage incur additional installation costs However such systems often re
116. outside air 64 63 62 LL 61 E 60 8 supply air temperature D cg reset by demand 2 w 58 D on E Oy g 56 gt a 55 OTRO ORO RORUORORORORORURUUROROROCURDORODORURUURUDORORORORNUT i fe T e 32 54 5 Ep 2 T E Ep 53 52 40 50 60 70 80 90 outdoor dry bulb temperature F Application considerations m Cooling loads that are being served by higher supply air temperatures often require more air and increased fan energy m VVhen the outdoor air temperature is less than the supply temperature the compressors can be shut off and an airside economizer can provide the needed cooling m The use of warmer supply air can result in higher space humidity levels especially during humid weather Related reading E Rooftop VAV Systems Applications Engineering Manual Trane literature number SYS APMO07 EN CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 51 Supply air temperature reset 1 In Create Systems select the Options tab for the system to which supply air reset is to be applied Click the Advanced Options button 2 Select a utilization schedule that accommodates supply air temperature reset A custom schedule can be applied 3 Optional Enter the maximum reset temperature difference Note When the utilization schedule reads 1 or greater supply air temperature reset will be enabled 5 52 System Control Strategies Sample scenarios Table 5 1 Sample Scenarios
117. oversized See Oversizing plants on page 6 95 Once baseline capacities are determined select the appropriate equipment from the tables in Section 6 of ASHRAE 90 1 2007 6 94 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Modeling for LEED Method 1 Oversize the coils Oversizing plants One of the often overlooked Appendix G requirements for the baseline building is the requirement to oversize cooling plants by 15 percent and the heating plants by 25 percent TRACE offers two methods for modeling oversizing Choose only one of these methods Method 1 Oversize the coils Recommended Method 2 Oversize the plants BP irese Systems Healing ate Cooking Ceil Orerrides hernia 2 socks Sites Y L i tz i Cre 1 n r m B mabe oiui Fobia 9055 Miri Flows Deina Create Syste gt Oversize cooling by 15 man select the Coils tab Capac Dan T Eeay ined 2 ma Tal enp Combing Capacity Aesishle A 2 Oversize the cooling and antes a cl Denar taos per _ Note The capacity units for Main heating coils as shown Pat 2 Shs a Dain Casey swe Cooling and Main Heating must be ua Ae i hal eta ake ieiki ii if a 4 7 Oversizing the coils will of Design Cooimg Capacity ann automatically carry over to the ve Oversize heating by 25 of Design Capacity respectively equipment section and size the Note In TRACE 700 the be plants appropri
118. p Evapa Cooking O Errira e Powered VAV Tyee A fexedtrarect ts Stage 3c sie Desci efficiency 5 orp e am Li 1 Describe the type of Dieci cod schedule E aata 6 om 2 Meow fi SCS evaporative cooling a en Sehedide 6 amto 6 em z Indirect coil schedule E or to E pm J2 desired For this scenario om d h l i Sane T Al dcndlt Energy lacevvasy T randier Max outdoor air sets the pick Staged Evaporative Typa Fena l maximum limit for outdoor CA airflow as a percentage of main supply airflow Cooling with the indirect coil activating first 2 Specify the efficiency of each coil and when it can operate schedule p F Note Refer to Creating schedules on page 6 137 3 Choose an economizer for information related to creating schedules type that describes the type of control desired dry bulb temperature in this case 4 Set anon point to describe when the economizer should be enabled Abemstive 1 System description Syvtem 001 Semt FanrPoweed VAV 5 Specify how much outdoor Fan cycing schede 1o tan cycing 4 air can be brought into the building max outdoor air and when the economizer can operate schedule aa i vat v KWCinrin wg Gam tobpm weather permitting mr kW m Avalable 100 kwi Cim Avelatie 100 rora eha lt 0 kwi Cim Avellathe 100 6 Enter the static pressure r kwiCIm vedsble 100 phe ee lo kwi Cim Avaitsble 100 that
119. parallel arrangement the first chiller attempts to 17 s satisfy the entire cooling demand If it cannot the a second chiller comes on and they share the load Verify that th ling onl erity that the cooling only proportionally chiller is the first farthest left chiller in the start SEQUENCE Crore plore O00 Het rector Cooking ori Cher Ty a l 3 Define the cooling only on Wate cde Hout abient wet bu ote chiller using the entries mamno RR shown for equipment type sequencing type and cooling capacity Also enter the full load consumption for each imap hed water Evh water p um p z Condens webs Enel vol ond abet pump CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 25 Thermal energy storage The on peak control strategy in this scenario calls for the tanks to satisfy the cooling load Use the Library Template Editors program to modify an existing piece of thermal storage equipment 4 i In the Thermal Storage library copy the Climatice equipment type and rename it 5 Pick an appropriate schedule and specify the storage capacity 6 Choose storage priority as the discharge strategy control type When scheduled to discharge the tanks attempt to satisfy the entire cooling load If there is not enough stored cooling the tanks discharge completely then mechanical cooling satisfies the load dhs Return to the Create Plants window of the TRACE 700 project
120. recommended to use values of 0 percent for hours off and 100 percent for hours available to run to avoid confusion TRACE 700 User s Manual e CDS PRM001 EN Dedicated outdoorair systems 6 Select the dedicated ventilation deck location This tells TRACE 700 where to supply the preconditioned outdoor air For this scenario the outdoor air will be delivered directly to the spaces As a result Room Direct will be selected Select the level of the ventilation deck location For this scenario one large dedicated ventilation unit will condition the outdoor air for all of the rooms assigned to the fan coil system so the coils should be set at the System level CDS PRMOO0O1 EN TRACE 700 User s Manual Return Outdoor Deck conditioned outdoor air is mixed with the return air in the main unit s Plenum conditioned outdoor air is delivered to the plenum above the spaces Room Direct conditioned outdoor air is delivered directly to the spaces This can also be used to model the delivery of conditioned outdoor air to dual duct VAV boxes where it mixes locally with recirculated return air Corg SA dewpontkwint O F Crinag cod OG oes Roem Hesrgcd avae A a or etnble V0 W Create Systems Dedicated Ventilation Sytem depcription Fan Gods ard DOAJ Cocina Heating Design Sepat Cooling upph sr dy bub 70 F Heating igph ar dry bub E3 ouir cupph a dew para l
121. refer to Balancing airflows on page 6 60 for additional details Load Design and Energy CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 9 Common modeling mistakes 6 10 Selection tab of Create Systems Spile de ririri Tampe Coritarnd Yaka Gyre Sylo Ippe Competes boom Liri Sup Feta Er Tiii Supply a paih di beets Fen Ain Mishan sat path be Mieri ak eai F phar Thies Check yaam verkistan Hag Eum Rem Re oooO Appi ASHEL Sed GE 1 202007 People Avene O Ft ASHRAF SiG Max Ver 2 Fists Aswad Populate Devertity ner DC Reardon 100 COPbased DOV Moe i Wier The fell marked ii iod are mone components of fhe E For the VAV systems the fan and or coil sizing methodology has been changed from block to peak VAV systems should be sized according to the block methodology This will lead to the program simulating a system that does not actually exist and may cause the system to be oversized Load Design and Energy For the constant volume systems the fan and or coil sizing methodology has been changed from peak to block Constant volume systems should be sized according to the peak methodology This will lead to the program simulating a system that does not actually exist and may cause the system to be undersized Load Design and Energy Note For more information related to the sum of the peaks and block sizing methodologies refer to the topic Block vs Sum
122. schedule if the default calculation methodology is being used or if all of your weekdays are charged the same rate Switch to Full year if Mon Fri have different rates if you are using the 8760 calendar and if you imported 8760 weather Reduced year schedules can be used In 8 60 simulations Full year schedules should not be used in reduced year simulations 6 166 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Creating utility rates 1 N Ww CDS PRMOO0O1 EN TRACE 700 User s Manual Adding weather locations and activating the 8760 calculation methodology Find the weather location that you want to import trom http doe2 com Download Weather or another Web site that has 8 760 weather or an importable format Refer to Step 5 to determine importable formats Download the weather file and rename the weather bin files to the appropriate extension For example a lacrosse bin weather file in the tmy format should be downloaded and then renamed to Lacrosse tmy before the import occurs Click Weather on the Libraries menu the Library Template Editors program opens to the Weather library The TRACE 700 weather library contains more than 500 worldwide reduced year weather locations Users can add new reduced year weather and new 8 60 weather locations by using the weather import feature This example discusses adding a new reduced year and 8760 weather location steps 1 9 and swi
123. second piece of equipment M Specify the full load energy rate or head pressure for each pump to account for pump energy consumption in your analysis Omitting this information tells the program that the pump does not consume energy m lo add new pieces of equipment to a TRACE 700 library copy and modify an existing equipment definition Note Exercise particular care when creating new pieces of cooling equipment Modeling accuracy reguires that the unloading curves represent performance characteristics at comparable design conditions The standard unloading curves used in the TRACE 700 Cooling Equipment ibrary are typically based on rating conditions defined by the Air Conditioning and Refrigeration Institute ARI Refer to Creating equipment and unloading curves on page 6 143 for additional details E lable 2 2 on page 2 26 shows the fuel types and corresponding units of measure that TRACE 700 uses to model various equipment CDS PRMOO1 EN TRACE 700 User s Manual Program Overview 2 25 General modeling hints Esasen Prats Dri Ura Minato Constant Vielume Hanmer Lorian Vokai Moore Hastra nde haar Pani harPowsed VAV Hig Dal on Pien Gaii hirr F ovaiid VAV 2 26 Program Overview General modeling hints Table 2 2 Default IP units for equipment energy use Description Consumption Peak electricity kWh kW natural gas therm therm hr fuel oil A therm 100 000 Btu or
124. should be used to select the fan and the coil airflow 14 676 should be used in the coil selection The problem however is in selecting a piece of cooling equipment when the fan and coil have different peak airflows Selection of the cooling unit prompts the user for only one airflow Therefore the fan airflow the higher of the two should be used to select an air handler Conservative selections should also use the coil airflow as a check for coil leaving conditions dry bulb and humidity with this smaller airflow Also be sure to verify that the higher airflow will not cause moisture carryover for the selected cooling coll 4 Trane Official Product Selection Software TOPSS can be ordered by contacting C D S at www tranecds com or from the TRACE 700 application click Help gt Trane on the Web Note Because the airflow is constant in a constant volume system the airflows at the time of coil and space peak will be the same Note For additional information regarding how TRACE 700 calculates airflows and the other numbers reported on the output reports refer to Frequently asked questions on page 6 20 or to the Design Output Interpretation Manual located in the documentation folder which is typically found at CA CDS TRACE700 Documentation Note It is recommended against using the calculated cooling colil leaving wet bulb temperature because TRACE 700 simulates using a generic cooling coil model which might have perform
125. siose Nore T Nore jor haie anod ed a Plate and frame heatenchanper appiaach 7 F Cooling and Heating Plants Airto air heat pump system 3 67 Water source heat pump system alls A TRACE 700 generates a special report for HVAC designs that include water source heat pumps The Thermal Storage report provides an hourly profile of ambient conditions plant level cooling loads heat pump loads and energy consumption and condenser loop temperatures 3 68 Cooling and Heating Plants Watersource heat pumps WSHPs transfer heat from air to water and vice versa Piping the heat pumps together in a common water loop creates a heat recovery system that can redistribute heat where it is needed for example from interior zones to perimeter spaces This capability saves energy by reducing the operating time of the cooling tower and boiler It also makes applied WSHP systems popular in commercial buildings that have many spaces with dissimilar cooling and heating needs In such applications each space is served by one or more heat pumps and is controlled independently WSHP systems readily adapt to the special requirements of speculative jobs because only the heat pumps required for the initial phase of occupancy must be procured Additional heat pumps can be purchased installed and connected to the loop as needed This offers the opportunity to meter individual spaces so that the tenants pay the individual operating cos
126. so on unless a definition has been created in the selected rate structure 6 164 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Creating utility rates 1 Click Rate Structures on the Libraries menu The Library Template Editors program should open up to the rate structures 2 To create a custom rate structure click New Structure Give the rate structure a name by deleting the default description and entering your own Avoid using any non alphanumeric characters in the name 3 Click New Definition to start defining the rate structure and select the utility that you would like to define first In this case start with electric consumption CDS PRMOO0O1 EN TRACE 700 User s Manual alpi xi IIA Temas 4gee P Fie Vew Opfttora Widow Help otz te G i Aata Definition Description rosin DAO hate 2 l Unity ime Commeris P Miron charge era Stat peand January 2 N Oefred cates End peiod Demam Kasan Flote ype Jon pex Mirim demand fi wal achuvtmert 3 Customer Charge 200 Og Ocie In this example the utility charges are based on the preceding rate structures f which include a kWh kW flag After selecting electric consumption the kWh kW flag should be selected as yes Selecting yes causes the program to interpret cutoffs below 500 as having the units of kWh kW variable cutoffs and cutoffs above 500 as having units of kWh standard The kWh kW cutoff
127. space Load Design and Energy m The energy meter is selected as none The heat given off by the miscellaneous equipment will still be calculated correctly however the energy consumed by the miscellaneous equipment will be neglected Typically electricity or gas should be selected for this field Energy Only m Ihe energy meter is selected as a cooling load or a heating load The energy meter tells the program what utility type is being used to produce the given internal load Typically electricity or gas should be selected for this field For example if heat gain from a computer is being modeled then electricity should be selected If heat gain from a Bunsen burner is being modeled then gas should be selected as the energy meter Energy Only CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 7 Common modeling mistakes Airflows tab of Create Rooms FP Create Rooms Airllovs Abemar 1 Rien dearer Sample ited N Templsien Man puboA Rom Dely Cooking howo era Aahar on aita liom pate a rt Loidi m Ihe ventilation schedule is using an internal loads schedule any schedule that starts with People Lights or Misc is an internal loads schedule Internal loads schedules should never be used for ventilation Internal loads schedules are zero percent for the heating design calculation This will cause the program to neglect the ventilation load for heating design This tends to l
128. system Is not going to allow the room setpoints to setback this far the values need to be overridden Not correcting this input will result in an underestimation of the cooling and heating energy during hours of reduced occupancy Energy Only Cstat and Hstat have been selected for the Thermostat schedules These schedules will allow the building to drift up to 95 F and down to 55 F depending on the time of day the schedules can be viewed by clicking Schedules on the Libraries menu Typically users need to either create their own Thermostat schedules or select none and let the program use the driftooints the schedules override the driftooints Not correcting this input will result in an underestimation of the cooling and heating energy at night Energy Only Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes Roofs and Walls tabs of Create Rooms Room Gesceghen S amgie Room Tag fwes Wal Comatruct 4 Lw Block 5 Ins irteinal Diet out hd Langh 0 m Utter 0 051 Bratt F Aii Den M Heie fi k Ta o deg Tata De T Grnd eefiect 1 Direction 270 deg Constr 1 Velge Gloss 5 bx Type F lengh 6 R Udacto 05 Biante Height E Ro Sh Coot 05 Qury D LdwRa D x Intera None E Roofs with no area length x width have been input Roots should be deleted not zeroed out if they do not exist This can lead to errors in the calculations and o
129. system is required to implement duty cycling To ensure occupant comfort the BAS should temporarily suspend duty cycling if the temperature in the space is outside the accepted range m Duty cycled equipment starts more often which accelerates wear and Increases maintenance costs m The sound of equipment being turned on and off at regular intervals may disturb occupants CDS PRMOO01 EN e TRACE 700 User s Manual System Control Strategies 5 47 Duty cycling ih In TRACE 700 duty cycling is modeled similarly to the optimum start stop strategy refer to page 5 6 As in that scenario duty cycling is implemented by a building automation system BAS 1 Use the Library Template Editors program to create a custom fan schedule from the scenario description The 6 a m to 6 p m schedule defines when the supply fan normally operates that is Monday through Friday from 6 a m until 6 p m The schedule definitions for cooling design and heating design are identical A separate definition for Saturday and Sunday not shown schedules the fan off from midnight to midnight 2 On the Fans tab in the Create Systems window of your TRACE 700 project choose the desired operating schedule for the supply primary fan 5 48 System Control Strategies Duty cycling Sample scenario A fan is subject to duty cycling for no more than 20 minutes each hour between 6 a m and 6 p m Duty cycling is not permitted if the temperatu
130. templates before creating rooms Project templates apply to only one file 7 Globaltemplates can be used in any number of files They are created from the Library Template Editors program Global templates are created in a very similar process and are used when the same type of buildings will be modeled repeatedly 8 A Project template cannot be exported to a Global Template Create a Global template to make it available for any Tile then add the Global Room or individual template into the Project 10 When editing information always check the upper left hand corner of the screen to ensure that the correct alternative is being edited Also verify that the correct template is being edited 11 For additional details on how to use alternatives and templates please refer to Creating alternatives on page 6 131 12 In Component Tree view the user can press ALT Z to revert the selected overridden value to a templated value quickly 6 130 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Using templates Creating alternatives Alternatives can be created efficiently using three options Use Copy Create based on and Create new E Use Copy Simulation will use data from another alternative which minimizes calculation time and will not increase file size Note The Use Copy option should only be applied to sections of the alternative where no changes will be made because the user will not be abl
131. the Proposed alternative based on Standard 62 1 2007 Addendum DA to Standard 90 1 2007 had its first public review in February 2010 and has an exception that states that if the Proposed alternative is designed based on the Ventilation Rate Procedure in Standard 62 1 then the Baseline alternative shall also be calculated using the Ventilation Rate Procedure with the following change Baseline zone air distribution effectiveness shall be changed to Ez 1 0 per each Proposed zone having a zone air distribution effectiveness Ez gt 1 0 Addendum DA will be voted on in an upcoming ASHRAE meeting and might be included in 90 1 2010 If this happens then the following procedure will not apply to any project that will follow ASHRAE Standard 90 1 2010 6 88 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Modeling for LEED 1 Model the ventilation in the proposed alternative following the steps shown in the ASHRAE Standard 62 1 procedure on page 93 2 Run the design calculations of the proposed alternative to obtain the total building outdoor airflow which can be found in the Airflows section of the System Checksums report 3 Divide that number by the square footage of the building which is listed in the Areas section of the System Checksums report This will provide a cfm sq ft value to be applied as the cooling and heating ventilation rate for all rooms in the Baseline alternative preferably usin
132. the addition of moisture would be detrimental to the system Figure 4 12 and Figure 4 13 on page 4 35 show the typical arrangements for sensible heat recovery in mixed air and dedicated ventilation systems In Figure 4 12 which shows mixed air systems sensible heat recovery can be used to reheat the dehumiditied supply air Insets A and C or to precondition the outdoor air Inset B Figure 4 12 Mixed air arrangements OA 4 34 Inset A parallel recovery stream to stream System Design Options Sensible wheel RA EA RA EA RA SA JOA SA JOA Inset B parallel recovery stream to stream SA Inset C series transfer upstream to downstream In Figure 4 13 on page 4 35 which shows dedicated ventilation systems sensible heat recovery is often used to reheat the dehumiditied outdoor air Insets A and C or to precondition the outdoor air Insets B and C Insets A and C are typically used with systems that deliver dehumiditied outdoor air at a neutral dry bulb temperature TRACE 700 User s Manual e CDS PRMOO1 EN Figure 4 13 Dedicated ventilation arrangements EA EA OA OA SA JOA SA SA Inset A parallel recovery Inset B parallel recovery Inset C series transfer stream to stream stream to stream upstream to downstream Each of the arrangements in Figure 4 12 and Figure 4 13 can be modeled using TRACE 700 However only the arrangement shown in Figure 4 13 Inset A will be covered
133. the condenserwater flow rate above the minimum limit recommended by the chiller manufacturer Monitor the condenser approach temperature to check for fouled tubes Related reading E Multiple ChillerSystem Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN Sample scenario A 500 ton three stage centrifugal chiller is designed for a condensing temperature of 85 F The leaving tower set point is reset downward to 55 F when ambient and operating conditions permit usually when a 20 F to 22 F differential exists between the water temperatures entering and leaving the condenser TP The following examples demonstrate two ways to model condenserwater reset by regulating the condenserwater You can model either temperature page 5 28 and by varying condenserwater flow temperature based reset page 5 29 Both methods require you to copy and modify an or tlow based reset but existing piece of cooling equipment not both CDS PRMO01 EN e TRACE 700 User s Manual System Control Strategies 5 27 Condenserwater reset yy Use the Library Template Editors program to customize an existing piece of cooling equipment 1 Open the Cooling Equipment library and choose the Equipment type that best matches what you want to model 2 Click Copy 3 Replace the generic name for the equipment type with something more descriptive and add comments if desired 4 Specify the lowest permissible condens
134. the deized equpment calegoty lo the Cong zaton bee W Create Plants A ype Equpmert Category facodied Arcod Wale co Waterco chiw p uday et Plant tantrad m E Desiren Desira plaea O01 i Sonne methane Fek Barid das iiajn dirado Walt Ele tasca he terse es emm Type tore T i zs q e wwet babs tier As conied Cockerg Pu Cogerenation typa condencer lover Secondary dribun pomp Toan Thermal storage Tue nss ulgi Coy Poo fee Bove Utay Misc Accessory Tehei own Etara torron Desenpian 4 mi names Mack based on dang omulsion n Remember that the pump must Tee ere now overcome the pressure mised veel cc aes drop through the chiller Cre SSC eee evaporator The power is Heng tats Ag a therefore larger than the secondary pump in a primary Theta eiii type Nowe secondary system Tihei Br ii F CDS PRM001 EN TRACE 700 User s Manual Cooling and Heating Plants 3 15 Variable primary flow chiller arrangement Cooling plant Coolers plant 003 Heat rayecton Equipmert tog Watercooled chier 007 7 Type Coorg tore for Cort Chillers x Equpmert caegoy water cooled chiles Hourly ambient wet bulb offpet Equapmert lype Deiak water cooled chiller Thamal storage gt Sequenang ype Sirge Type None 5 Click the Cooling Equipment tab to access the chiller information 6 Input the specifics of the first chiller by a Renaming t
135. the heating demand increases Application considerations For a load shedding economizer to operate as intended the temperature and humidity outdoors must be low enough to provide effective cooling m When specifying equipment for the chilled water plant the chiller must be equipped for condenser heat recovery and the control system must be capable of balancing cooling and heating demands to optimize the operation of the economizer Sample scenario A chilled water plant includes a three stage centrifugal chiller equipped for heat recovery and a load shedding economizer During the standard cooling mode the chiller can produce 500 tons of cooling while consuming 0 58 kVV ton When operating in the heat recovery mode the chiller can produce 400 tons of cooling and consumes 0 70 kVV ton Mas Coolers pare 001 ag Heat recowery chs t1 Heating plants Iles Heating plant 002 D Gaited bode w ijg Ha iz n mnj Enoy Mgmt EErEE Bove Utiity Misc Accessory CDS PRMOO01 EN TRACE 700 User s Manual System Control Strategies 5 31 Load shedding economizer 3 Choose a boiler type 4 Enter the static head to represent the full load consumption of the hot water pump 5 Select a heat recovery chiller as the equipment type 6 Specify the capacity and energy rate for each operating mode cooling and heat recovery 7 Enter the full load consumption for each pump 8 Assign the heat recovered
136. the primary Supply Ahoy kw 70m Avadstle 100 fan must overcome 4 42 System Design Options TRACE 700 User s Manual e CDS PRMO01 EN Direct and indirect evaporative cooling llay Next define the cooling and heating plants that satisfy the coil loads 7 Add a water cooled chiller and a boiler to the main cooling and heating plants respectively Not shown On the appropriate tabs define the equipment type and full load consumption for the pumps 8 Create a new cooling plant to represent the cooling provided by the evaporative coils and permit proper coil assignment in Step 10 Replace the generic identifier with a more descriptive name for easy identification 9 Define the evaporative cooling plant by choosing the appropriate equipment type and entering the full load consumption for the pumps 102 Assign the system and associated coil load s to the proper plant W Create Plants Abemstive 1 jar N che usar i s im HET Incheect them deect ooking wv P _ Heating plants me How Cig Piori I milas Heating plant main hig iniia Water Bode Electic Gatfrei E Boder 001 source he fecutance hes x ee P Arcocded Cookery Purga Tt Cancel a tomer a Energy Mont To stapi equement dag the dained equement calegory lo the Conia zahon bee Configuration Lilane Heating Equipment Bove Utity Misc Accessor Cooling plant Eee He
137. to the high efficiency of large chillers and so on In addition thermal storage can be used by the utility to allow generation of the chilled water at night when off peak energy rates may be available and distribute it during the day when needed by the customers Application consideration m Purchased chilled water can offer lower first costs but life cycle costs may be higher Related reading m Purchased chilled water purchased district steam and purchased district hot water are all modeled similarly in TRACE 700 Refer to Purchased district steam and purchased district hot water on page 3 40 CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 37 Purchased chilled water Sample scenario In this example the building being modeled purchases chilled water from a central chilled water plant owned by the local utility The building owner pays only for the chilled water and the electrical use of the chilled water pump 1 Masstart by clicking Create Plants a Aactooed Ancoed Waterco chee utay chiller 2 From the Equipment Category section on the left side of the screen click a Water Cooled Chiller and drag it over to the cooling plant 3 38 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Purchased chilled water 3 Click the cooling plant click Edit and rename the plant 4 Click the Cooling Equipment tab 5 In the Equipment Type list click Purchased Chilled Wate
138. value from step 7 The default value was determined using the efficiency rating CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 99 Modeling for LEED associated with the particular piece of equipment per Tables 6 8 1 from the 2004 standard As long as the previous steps were followed utilizing values from the 2007 standard the value from step 7 will make the selected equipment compliant with the 2007 standard Additional equipment considerations As with the baseline building systems Appendix G dictates additional equipment requirements based on the system type Following is a list of additional equipment requirements that may need to be included Many of the equipment types found in the 90 1 2004 and 90 1 2007 Minimally Compliant Equipment Libraries contain their applicable requirements Note This is not a complete list ASHRAE 90 1 2007 is the primary source for determining if these or any other equipment requirements exist m ype and number of boilers m ype and number of chillers mM Heat pump requirements E Hot water reset m Chilled water reset mM Pump requirements Utility rate structures Use the same rate used in the proposed alternative Calculating the file Appendix G requires the baseline building be rotated in four directions with the report of the results to include the average of the four rotations TRACE includes an automatic rotation feature that satisfies this requirement Use
139. ventilation systems In Figure 4 3 which shows mixed air systems sensible heat recovery can be used to reheat the dehumiditied supply air for independent control of both temperature and humidity Insets A and C or to precondition the outdoor air Insets B and C Figure 4 3 Mixed air arrangements EA RA EA RA EA RA OA S SA JOA e SA JOA SA Inset A parallel recovery Inset B parallel recovery Inset C series transfer stream to stream stream to stream upstream to downstream In Figure 4 4 on page 4 10 which shows dedicated ventilation systems sensible heat recovery is often used to reheat the dehumiditied outdoor air Insets A and C or to precondition the outdoor air Insets B and C Insets A and C are typically used with systems that deliver dehumiditied outdoor air at a neutral dry bulb temperature Each of the arrangements in Figure 4 3 and Figure 4 4 can be modeled using TRACE 700 However only the arrangement shown in Figure 4 4 Inset C will be covered in this discussion of coll loop energy recovery For arrangements other than this one select the appropriate energy recovery configuration similar to step 2 in this example and refer to the following CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 9 Coil loop for exhaust air energy recovery Figure 4 4 Dedicated ventilation arrangements EA OA 4 10 Inset A parallel recovery stream to stream System Design Options
140. were created 2 Typical values and explanations for all fields can be found by pressing F1 to access online Help 3 Daylighting can affect all sections of the building simulation depending on the daylighting schedule selected on the Room Parameters tab For cooling load design the cooling load and airflow will both change based on the lower lighting load possible increased solar loads changes in plenum temperature and changes in time of peak The heating design simulation will also be affected but the effects may be smaller than the effects on the cooling design simulation due to the typical neglecting of the solar and internal loads in heating design calculations In TRACE 700 two alternatives one with daylighting and one without daylighting can be used compare the overall effects of daylighting on the rooms systems plants and life cycle costs The checksums reports can be used to view the effects on the design calculations for the rooms and systems usually a reduction in cooling capacity and airflows occurs The energy consumption reports can be used to view the effects on the olants usually lower lighting energy lower cooling energy and possibly higher heating energy because the heat given off by the lights in the spaces is less The economic reports can be used to see the reduction in utility costs and the effects on the life cycle cost for the building Note For conservativeness it may be desirable to disregard dayl
141. which have a useful capacity of 2 000 ton hours discharge between 11 a m and 5 p m and charge between 11 p m and 7 a m Assume that the tanks are virtually empty at the end of each discharge period At all other 3 22 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Thermal energy storage Mls When a single chiller charges the tanks in a thermal storage application storage characteristics are defined at the chiller level 1 Add a chiller to the cooling plant 2 Describe the chiller type 3 Define the capacity and full load energy rate of the chiller when cooling 500 tons at 0 65 kW ton and when charging the storage tanks 335 tons at 0 78 kVV ton 4 Specify the full load consumption for each pump 5 Choose an equipment operation schedule that makes the chiller available for thermal storage 6 Describe the parameters for thermal storage by entering the type capacity and schedule Note If the user does not specify capacity or energy rate in tank charge mode or select a schedule allowing thermal storage the tanks will discharge but never recharge times the chiller runs in standard cooling mode to satisfy the cooling demand Note To properly model this scenario be sure to enter the capacity and energy consumption of the chiller during both standard cooling and ice making modes Cookery plants Mes Cooirg plant 001 BY Watercooled chiller 001 2r Cooling to
142. will automatically neglect solar loads during the Heating Design calculation By the same token It is Important to account for scheduled loads such as ventilation and infiltration which contribute significantly to the building heating load To include a load ventilation infiltration and so forth in the heating design calculations set utilization value to 100 percent for the Heating definition For additional information related to schedules please refer to Creating schedules on page 6 137 CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 23 Frequently asked questions Q Can change the default weather location A To change the default weather location first close any open files Then on the File menu click Customize settings In the default Location field type in the desired weathertfile description exactly as it appears in the library Q How do model a latent miscellaneous load A To do this you must first create a custom miscellaneous equipment library member Click Internal and Airflow Loads on the Libraries menu and select the library tyoe as Miscellaneous Loads Press New or Copy to create a custom miscellaneous load Here you can define the total load and the percentage of the load that is sensible The remaining percentage is considered latent load Fill in all other relevant fields for the custom miscellaneous load and click Save Now you can utilize this new library
143. will be upstream of stage 2 6 Choose the schedule that describes when the coil loop is permitted to Stage 2 Airtoais Eneigy Recovery Teanate Stage Altos Energy Recowerp Transter Type Cod loop sares supply as tampering operate The schedule Available 100 will allow the device to operate year round Sup tide deck Vertiaion dowrnitrean Eirexe deck Ventisson upsueam Schedde rvvestatle 100 CDS PRM001 EN TRACE 700 User s Manual Nore jdeiaa System Design Options Coil loop for exhaust air energy recovery 4 13 7 Input the coil loop effectiveness essentially how efficiently the coil loop recovers energy by clicking Effectiveness and entering the sensible effectiveness percentages at different airtlows Click OK and then click Apply when finished Note To further refine the model of the energy recovery device the Options button on the Options tab can be used to define such items as parasitic energy consumers such as the pump in this example static pressure drop bypass dampers part load controls economizer lockout and frost prevention 4 14 System Design Options Evaporative Cooling Type rion Direct efficiency 5 Dect cod schadhdo Heat eftectrveness at 100 astiow Indec eliaancy Heater ellectrverets af TST selb 15 Indrect cod schedule RE Lotert Stage Aatods Energy Reco Type ZA Couling effectvveress at 7S axfiow fo x Sup tide deck Vertiatior H
144. will cause cooling energy to be underestimated and result In erroneous airflows Load Design and Energy m Ihe input heating supply air temperature 55 F is too low The heating supply air temperature must be greater than the entered room setpoint for heating in Create Rooms This will cause heating energy to be underestimated and result in erroneous airflows Load Design and Energy m A Reheat Temperature Difference 25 F has been input This value Is typically used to model reheat done during cooling design typically for dehumidification Inputting this value can lead to extremely low leaving cooling coil conditions and oversizing of the cooling coil Load Design and Energy 6 12 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes Fans tab of Create Systems Abermonve 1 Sytem description Sample Constant Voke System Pai FarrPowered VAV Fan cycling schedule No tan cycing Lights Elementary kitchen Avelable 100 Avalie 100 Avelable 100 Available 100 Aveable 100 Avelsble 100 m The fan type has not been selected Without a fan type the program cannot calculate fan energy Energy Only m The fan static pressure has not been input Without a fan static pressure the program will not calculate fan heat pickup and possibly not fan energy Load Design and Energy m A fan schedule Lights Elementary kitchen has been input Typically the fan cycl
145. with a similar temperature profile or refer to Adding weather locations and activating the 8760 calculation methodology on page 6 167 for directions on importing new weather locations in TRACE 700 8 Click Create Templates click the Internal Load tab click Wing1 on the Description list and edit the data to properly model the internal loads in the building In addition the Wing1 Airflow Thermostat and Construction templates should be altered to properly model the building When all of the templates have been edited click Close 6 112 Advanced Usage and General Modeling Tips we TRACE 700 C CD5 TRACETOO Projects Variser Ind tre z lajxj Fie Edt Actors View Options Liearies Termgisles A enalives Setup Window Help Selo A ke eectkeve BS FAH Note The Overrides button can be used to view and or alter the design weather temperatures Intermmal Load Templates Project Fle Ect Acton Wew Project Navigator Detention e 8 ae Type General Other Space Cee Dernaty fia3 ia meron Schedde People Otce jaar Sensbie 250 Btuh Latent faw tuh Type Reversed harese ret verted B T load to space gt Hest gain fis Waan Schodde Lights Office hd Mucelbar recut loads Type Std Ottice E quapereord Enegy fo 5 Wrak Schodde Mac Lowe office gt Enay ase blectnety B _Intemat toad Aiton Themoax Construction Mall Cokuiste ond View
146. with heat recovery as the equipment type 2 Specify the capacity and energy rate for each operating mode cooling and heat recovery 3 Enter the full load consumption for each pump 4 Reject the heat recovered by the chiller to the heating plant when a heating load exists To model the heating plant in this example 5 Choose a hot water boiler as the equipment type 6 Enter the static head of the hot water pump as the full load consumption for the pump 3 52 Cooling and Heating Plants W create Plants S aloj zj Ahensive 1 Cooling plant Cookers plane 001 Heat rejection type feqsian Conakry towet Ee Equipmert tog Heatcecovery chiller 1 7 CE Equpnert category water cooled chile Thamal horace Equpmert type 2 Stage Cent w Hest Ree 105 HW 1 A Type None _NewEqup Sequencing yee srz Capacity fi fiore 7 Com Equo Schedule cixage d Delete Eqa Cooling Equipment Controls Reictheattoplat neam e a Eqipmeni schedule Arvaat O Chern kming priority B cate Plants Heating plara 002 Gai fred boder a Equipmert cotegoy oder Equpieri lype Gas Fred Hot Water Boer 5 Moh fea 3 Percent elficiont Mna Heatrg water cec pup z Double bundle condenser heat recovery Feja conckersiet haw Hesira plara 4 To accomplish condenserwater reset by varying flow rather than temperature choose a variable volume pu
147. with the coil s 2 The heating coil s have been scheduled off during hours when heating loads occur If the coil s are turned off they cannot consume energy Schedules for coils should be used only when the coils are turned off for certain time periods and not allowed to turn back on no matter what the temperature is in the space Example 7 Heating plat Bodes Plart Equipment tag Boder 1 Equipmert cotegcy oder Ecuapmert type Gas Fred Hot Water Boker Thermal storage Type nore x Cooacty O fiort z Eqbnatachedieforox F 1 oo prosty 1 The heating equipment schedule does not allow the heating equipment to run during hours when heating loads occur If the heating CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 43 No or low heating energy consumption equipment is turned off then it cannot consume energy or meet the calculated heating loads Note Switching to a full year 8760 analysis will typically provide a more accurate estimation of heating energy consumption Refer to Adding weather locations and activating the 8760 calculation methodology on page 6 167 6 44 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN No or low heating energy consumption Modeling large rooms and zones As a time saving measure users will occasionally choose to model large thermally diverse areas as a Single space The ramifications of this simp
148. your backup heating plant if necessary 8 Finally assign each coil load to the appropriate plant 3 84 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Variable refrigerant flow system O System Design Options Modeling examples in this chapter Energy recovery and dehumidification Desiccant dehumidification page 4 2 Coil loop for exhaust air energy recovery page 4 8 Total energy enthalpy wheel page 4 15 Fixed plate heat exchanger page 4 21 Heat pipe page 4 27 Sensible wheel page 4 34 System options Direct and indirect evaporative cooling page 4 40 Dedicated outdoorair systems page 4 45 Dual path air handler split dehumidification unit page 4 67 Systems with 100 outdoor air page 4 73 Cold air distribution page 4 76 Chilled beams page 4 79 Underfloor air distribution page 4 84 Displacement ventilation page 4 88 ASHRAE Standard 62 1 page 4 91 This chapter provides basic how to instructions to help you model system level options such as energy recovery Each example begins with a brief description of the option followed by a sample scenario that illustrates how to model it Typical values are suggested where appropriate CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 1 4 2 Desiccant dehumidification Desiccant dehumidification describes the use of a moisture attracting material solid or liquid in the air stream As Figur
149. 00 including this User s Manual the Getting Started manual the Knowledge Base Center online Help and easy access to the Trane home page on the World Wide Web personalized training is also available Click Helo and from the Help menu click Trane on the Web There you can find technical support service releases to download and other forms of user assistance usage tips and training opportunities for example as well as information about other Trane products and services This manual The TRACE 700 User s Manual contains step by step instructions to help you model common HVAC system options and control Strategies It assumes that you have a working knowledge of your computer and Its operating conventions including how to use a mouse and standard menu commands This guide also assumes that you know how to open save and close files and that you can use My Computer and Windows Explorer proticiently For help with any of these techniques please refer to your Windows documentation Chapter 2 of this guide explains how TRACE 700 is organized both behind the scenes and on screen Electronic manuals The following references are installed with the program To view one of these electronic manuals select it from the TRACE 700 folder under C D S Applications in the Start menu m TRACE 700 Getting Started Manual cds orm002 en pdf m TRACE 700 User s Manual cds orm001 en pdf m Design Output Interpretation CDS PRMOO01 EN TRACE 7
150. 00 User s Manual A Brief Introduction 1 3 About TRACE 700 1 4 A Brief Introduction About TRACE 700 Adobe Acrobat Reader software is required to view these and other technical documents included on the program CD ROM You can download the latest version of Acrobat Reader free of charge from the Adobe Web site www adobe com Samples Some example projects in the CDS TRACE700 PROJECTS subdirectory COMPLETEDTUTORIAL TRC and TUTORIALTRC TRC will help you get started Explore each file to acquaint yourself with the entries for modeling loads and systems in the TRACE 700 environment The electronic TRACE 700 Getting Started Manual provides a tutorial which demonstrates the steps used to perform various program functions Online Help The online Help for TRACE 700 describes how to perform basic tasks for example creating rooms and assigning loads to the HVAC system It also provides detailed information about each program entry To start online Help Do one of the following On the Help menu click Contents Press F1 Click on the toolbar From the Start menu select Program Files gt C D S Applications gt TRACE 700 gt Help To identify a tool or control Position the pointer over a tool or control and pause A ToolTip appears showing the name of the item For more details look up the name of the Item in the online Help index Internet resources If your system is connected to the Internet and a Web browser
151. 01 EN Airto air heat oump system E The Cooling Equipment library provides performance characteristics for each library member including the airto air heat pump selected in Step 3 7 To finish defining the electric resistance heat that will serve as a backup for the heat pumps select the heating plant on the Heating Equipment tab 8 Pick one of the electric resistance heat entries as the equipment type 9 Finally assign each coll load to the appropriate plant Note Electric resistance heat not only supplements the heat pump but also operates in lieu of the heat pump if the temperature outside is colder than the minimum condenser operating limit In this example the heat pump does not operate when it is colder than 40 F outside Use the Library lemplate Editors program to view or modify this entry in the Cooling Equipment ibrary CDS PRMOO0O1 EN TRACE 700 User s Manual M icone A Egimetiog Eene nene 0 n a mm Eaupment cotegoy Cieceres a i a Capacty Mon x COE TM Energy rate Schodde Sims Equement schedule Avedatie m00 paorly lia Elec iemitance OC Hesio System System 001 la Hex Pure E Geoling Equipment Main Cooling category Aircouied umay Commarts Equement bee air te A Heat Pum fu best pure Eq fel Aiject conderas has To mimenos ypa Henra rint E wap gente eincneenms E x AE Pad vaai be F Free Cooling 1 Thema
152. 1 Drag and drop two water cooled chillers from the Equipment Category section to the cooling plant 2 Drag and drop a pump from the Equipment Category section to the cooling plant 3 Click the cooling plant and click Plant Ctrl only active when the Cooling Plant is selected to activate the Plant Controls 4 On the Plant Controls screen select the Pump Type input the full load consumption change the plant sizing method to block plant and click OK Note To model dedicated VPF similar inputs would be required However rather than assigning one large pump at the Plant level the chilled water pumps would be entered with each piece of equipment on the Cooling Equipment tab A tm eg Aircooled Aincodled Waterco ETES Watercooled chides 001 chiller 4 tarce he pea An cocied E Thermal i ik Condense water pure 7 amp i Condense water pure Primary chilled moter puro la Heating plant 002 El EL A m sf e Aetcoed Arc ded Waterco Waterco chile ukay chiller Wi Phort wizard SH Cooling tower A u Condenser water pure How Cig Piara Primary chided water pure Water Electric SET Watercocled ch 002 New Hig Piara tarce he resistance T Dai ondencet water purno a a Po Raass ne 5 nad Heating plants As cocied Cocking Pumps Thermal lls Heating plore 002 Delete condenser x To stegn equement dag
153. 10 Mixed air arrangements Inset A parallel recovery stream to stream RA EA RA EA RA SA JOA SA JOA SA Inset B parallel recovery Inset C series transfer stream to stream upstream to downstream In Figure 4 11 which shows dedicated ventilation systems sensible heat recovery is often used to reheat the dehumiditied outdoor air Insets A and C or to precondition the outdoor air Inset B Insets A and C are typically used with systems that deliver dehumiditied outdoor air at a neutral dry bulb temperature Figure 4 11 Dedicated ventilation arrangements OA 4 28 Inset A parallel recovery stream to stream System Design Options Heat pipe SA JOA SA JOA SA Inset B parallel recovery Inset C series transfer stream to stream upstream to downstream Each of the arrangements in Figure 4 10 and Figure 4 11 can be modeled using TRACE 700 However only the arrangement shown in Figure 4 10 Inset C will be covered in this discussion of heat pipe energy recovery For arrangements other than this one select the appropriate energy recovery configuration similar to step 1 in this example and refer to the following TRACE 700 User s Manual e CDS PRMOO1 EN Figure 4 10 E for nset A refer to steps 1 through 6 in Fixed plate heat exchanger on page 4 21 m for nset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 Figure 4 11 E for nsetA
154. 2 Altos Enengy Recowen Tranater Type T l Tye Nore etna 7 ream Sup tade deck Vertietor upeteam 8 Extreade deck xx amp 100M edau ma J Extrside deck Outdoor 5 mom exbvaunt ms Schede Avaladie 100 Schedse Avvebsbie 100 bd Dephacemert Vertiston Undertioc Parameters Supply ae path duct location Pesan s Space eratio gars te cocupeed layer f 5 Urdei plenum heght f A Conducte iesstance of ianed ioo f r eit Fan Supply Duct Other Losses Upetrear nomna leat age hector 3 s Domrebeam Constant inah age hector 3 5 Arcokary Cooking Cod kares te phere fp N Aniar col lan corto methods Corod Meta t Ausdhary cooling cod F okove Ouwe As Roret Sc Peckse Fan ce od fw al Ausdhary heating cot F otom Outce Ar Meet 5 chedi fws Corectia Preogie Hospital bity Avoobary fan Corsare Voimme P Horeg al P gerd Ran gt Une pren deist cutecde s eoet Aatowe Sum of oor romena verison plane ong ad Supply a DB cooing kowe at outside ae DB Schade Avatatle 500 Suppi a DB cooling hgh a admi w DO pe The shoud represent the combined resistance of the carpet fi masti and the nared floor panel and should NOT wnchude ary an fin secniance These condol are qnored urien the audkary cig ot ho cod capacity ovome are Gofired on the Ceste Syrteme Heating Cod Ovemdes screen System Control Strategies 5 19 CDS PRMOO01 EN TRACE 700 User s Manual Unoccupied ventilation night purge Morning warm up for
155. 227 cfm Entering Cooling Coil Conditions DB WB 82 8 F 675 F Leaving Cooling Coil Conditions DB 55 F Altitude from Title Page report 263 feet qe ie CS Be TAHAA Tun ee ij Feb me m bhy enkem bremi ee ce rrr e G L i eee te 6 74 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Selecting a chilled water cooling coil using TRACE 700 output 2 These results will need to be input into the coil selection program In this case the Trane selection software TOPSS will be used to select the cooling coll Note When using a selection program it is often easy to overspecity the unit TOPSS changes the colors of required inputs to red optional inputs to blue and all other inputs to white Specifying only red fields will ensure that over specification does not occur 3 Start by inputting the type of coil chilled water the coil utilization for this example we will assume a standalone or shipping coil but you may also select a specific air handler casing which would then define the coil size the elevation 263 ft the airflow through the coil at the time of the coil peak load 24 227 cfm and the entering air conditions 82 8 F DB 6275 F WB 4 Next the capacity of the coil must be input Delete the unwanted default Leaving dry temperature of 55 F and press Enter Removing this value should activate the Total capacity field Input 1098 5 MBh for the
156. 3 3 describes the procedure for modeling chillers that are piped in a decoupled arrangement The examples that follow demonstrate how to model the equipment start sequence for each condition described above Cooling and Heating Plants 3 17 Switchover control for chiller plants lly To create a switchover sequence based on load 1 Select the cooling plant and open the Sequencing dialog box 2 Create two start sequences one that starts the centrifugal chiller first and one that starts the absorption chiller first 3 Pick Load as the basis for switching between sequences 4 Using the operator op load and units entries define the load condition that determines when each sequence will be used The program ocks in the first operator you choose gt lt gt or lt for the remaining entries This helps prevent gaps and overlaps in the switchover conditions 5 When satisfied with your entries click OK to save them 3 18 Cooling and Heating Plants Switchover sequence based on load For this example the cooling load determines which chiller starts first The centrifugal chiller handles loads up to 300 tons For loads greater than 300 tons the absorption chiller starts first If the current load is greater than the capacity of the first chiller in the sequence the second chiller restarts and both chillers share the load in proportion to their design capacities Configuration Am lt lt am
157. 3 titlepg html 5 42 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Daylighting Demand limiting Many utility companies face a shortage of generating capacity during periods of high demand To discourage energy use at these times they may implement time of day rate structures that charge a premium for electricity used during on peak periods Ratchet clauses minimum demand charges levy a further penalty Note Under a ratchet clause the peak demand set during a given month establishes the demand charge for the succeeding 12 month typical period The higher demand rate remains in effect even if monthly demand drops in succeeding months Demand limiting is a control strategy that restricts the amount of electrical demand for the HVAC system To accomplish this the building automation system BAS implements one or more temporary corrective actions when electrical demand exceeds a predefined level It increases the temperature set point in the zones modulates the speed of electric motors and or cycles off electric equipment Figure 5 11 Effect of demand limiting on electrical consumption no demand limiting with demand limiting electrical consumption of building peak rate period 12 a m 6 a m 12 p m 6 p m 12 a m Normal operation is restored at the end of the demand limiting period which usually lasts 15 to 30 minutes To avoid compromising occupant comfort the control strategy usually inc
158. 9 5 EER into kVWV ton and multiply by the building load in tons to determine machine power in kW Remember the baseline building cooling equipment needs to be oversized 15 If this was not accounted for when determining system tonnage by adjusting the coil size in the Coils tab of Create Systems then add 15 to the building load EER 12 kW ton 12 9 5 1 263 kW ton 1 263 kW ton x 150 tons x 115 2179 kW 4 Subtract the calculated system fan power from the total packaged efficiency 2179 kW 50 7 kW 1679 kW 5 Determine condenser energy For this example the condenser is air cooled According to Table 6 8 1G aircooled condenser performance requirements must meet or exceed 176 000 Btu h x hp Therefore 2 Lip tion h T hehp 0 746k1 12 0003 0 050871 kW ton 0 050871 0 941 motor efficiency 0 054 kW ton 6 The tons portion of the condenser energy the denominator is heat rejection and not cooling load The following approximation can be used to determine the heat rejection load Qcond 1 1 COP x Qevap Qcond 1 140 293 x 9 5 EER x 172 5 234 6 tons 7 Multiply the condenser fan power by the heat rejection load to obtain the condenser fan power in kW 0 054 kW ton x 234 6 tons 12 7 kW 8 Subtract the condenser energy rate from the energy rate calculated in step 4 1679 kW 12 7 kW 155 2 kW 9 Override the default value found in the Energy rate section on the Cooling Equipment tab with the
159. A OSARE IH YE O A A Be lAr 1 Open the drawing file in the Autodesk Building Systems ABS 2005 in this case Note Verify that the latest version of ABS 2005 is installed before beginning this process Autodesk products are updated with Live Update which downloads patches to your product using Communication Center Users can use Live Update to check for updates when a Web connection is established If a product patch is available notification of its availability is received on the AutoCAD status bar and the patch can be either downloaded directly from an Autodesk server or modified first before being copied to users workstations 2 On the File menu click Export to gbXML 3 Select the destination for exporting the gbXML data and the number of zones to export input the building type and zip code and click Start to begin the export process Save rhs Cirle Seas CDSVRACE TO Gee gh ML Eman Brenan Expewt Daak Spsbern bo YML 4 When finished click Close and exit out of ABS 2005 i TO See Objects 3 Tones siiociod 5 Using Windows Explorer C place the goXML export pm oo file into the TRACE 700 Projects directory Typically this will be CACDS TRACE700 Projects seme 4 thas 6 182 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN gbXML import and export Importing goXML data in TRACE 700 1 Open TRACE 700 and start a new
160. A TRACE 700 performs a separate calculation to determine heating coil sizes based on the heating design temperature As a result the heating loads are determined not from the monthly weather data but from the heating design temperature which does not have a month and time associated with it In TRACE 700 terminology and for reporting purposes this heating design month is designated as Heating Design on the Checksums reports Heating Design is only used for heating coil and fan sizing and only affects energy consumption in that it sets the heating equipment capacity thereby allowing the program to determine the part load point and unloading status for all other conditions Note that the actual part load conditions used for energy analysis are based on the hourly analysis data Utilization schedules include a special Heating definition used only for heating design calculations during the program s Design phase The Heating definition is not included in the energy analysis simulation only in the heating design calculations Per recommendations from ASHRAE many scheduled loads are typically not included in the heating design calculations For example loads associated with people lights and certain miscellaneous equipment should be excluded from the Heating design calculation to avoid taking credit for the heat they generate Io accomplish this set the utilization value to O percent for the Heating calculation Also by default Trace 700
161. ACE 700 User s Manual e CDS PRM0O01 EN Zoning of rooms It is Important to note that a room assigned directly to a system is a separate zone in TRACE 700 Therefore if multiple rooms are to be served by a single SZ or VTCV unit the rooms must be assigned to the same single zone underneath the system refer to the middle example above After calculations have been completed the user would want to look at the System Component Selection report or Zone Checksums not the Room or System Checksums for coil and fan sizing Information Room level coils fan coils Figure 6 5 Fan Coils ar Fan Coils aF Fan Coils gi Fan coils 1 2 East Room H g East Zone L y East Zone L E East Room La East Room AS west Zone FH Fan coils 2 L fe West Room L d West one L fa west Room FCU1 FCU2 FCU1 FCU2 TENT East Room West Room East Room West Room oll oll The following systems have room level fans room level main cooling coils and room level main heating coils by default computerroom unit fan coil incremental heat pump PTAC radiation unit heaters unit ventilators and WSHP With room level systems each room assigned to the system gets a separate unit If a building with 200 rooms is going to be conditioned by 200 fan coil units with similar input criteria as defined in the Create Systems window of TRACE 700 then only one airside system needs to be created All rooms would be assigned to this system and TRACE 700 would cal
162. Application considerations m The control system must monitor the outdoorair and return air enthalpies and control the outdoor return air dampers and fans accordingly 5 2 System Control Strategies TRACE 700 User s Manual e CDS PRMO01 EN Airside economizers oF To model an airside economizer with enthalpy based control complete the following entries for the selected airside system 1 Choose an Economizer Type to define the basis of operation For this example pick Enthalpy 2 Ensure that On point is blank Note If comparative enthalpy control is not available input the desired On point 30 Btu lb is typical for enthalopy based economizers Notice that Btu lb is used instead of F as is used with dry bulb economizers 3 Define the maximum percentage of outdoor air A value of 100 lets the outdoorair dampers provide up to 100 percent of the supply airflow for cooling design 4 Select a schedule to define when the economizer can operate provided that outdoorair conditions are suitable CDS PRMOO0O1 EN TRACE 700 User s Manual Select a high quality enthalpy sensor low cost sensors are often short lived and require frequent replacement Avoid placing the sensor in direct sunlight or near heat sources Consider the climate when assessing the appropriateness of airside economizing and setting an economizer control point Bringing air that is too moist or too dry into the building can
163. Ba TRE T Puteri alerck T Eneng Tuara 2ra F TRAGEOO w Ej inate Taha saa THE Z Trini TOD bre Ej Fene iti 3 Fisi al Bape TRACE PON Fiss Cancel l Ea CP enacge Tutor RIA TRE Tria i T LEvworiala E Tramro0E F Turism T Tutoriale T TRAC EOOOBAK TRC Z Tunoriaeroe Z tac loa tre j wj Fis name TAACEONA ue ten 42 me Ereg tonal Fiii cof papa trace 70D Fiag Cancel aa Advanced Usage and General Modeling Tips 6 177 Combining files 5 Decide if you would like irae roa to merge the cooling and GQ eee wap a ag heating plants for the files Cen yau mh bn meng the pisri Coe 5_ 6 Select the alternative that CACDSATRADE 700 Aropo te 2 be Poprad Dedy will be merged into the E m atg file C aa Moi Ii ary ol ihe giemaiver in the bored on fie are unnamed Note For all files after the ikea pach a uria Grseroton balaa procesdng THs 2 2 z tbai far iaae ral mabch lha aider ri lha Eata ori Ibe first file a unique prefix will be entered so that the Ura prele hor contand Hes 2 templates airside systems and SO on all have unique me IRALE 70D for rxrhrive use by CACDS TRACE TOD Projects Comisrsed Pile i names Fle Edt Amoa View Options Lbwaries Templates Abenatives Set Window Help JSa eihoe A Eaeetkeve RAH Project Navigator a es 1 a 7 TRACE 700 will create a new file with all of the selected files data combine
164. CDS PRMOO0O1 EN TRACE 700 User s Manual Evapora prenncling n Ha E wap preooel alocati E x Thama signage hype Hone Heat rjeci ype Emm Coping beaver Rajni contrast hes To minene ipype oe At hol vanis ter F gt Free Coire Tyo Hore Fhad coke tne Five coving pump lise Pumped ff fiw Plate and frame Fea exchanger approach 7 F System Control Strategies 5 29 Condenser water reset Load shedding economizer Conventional practice uses an airside economizer to satisfy internal loads when ambient conditions permit and thereby minimize operation of the mechanical cooling equipment Similarly recovered condenser heat can be used to supplement an auxiliary source of heat to offset thermal heat losses in perimeter zones A load shedding economizer saves energy by combining these concepts to minimize the operation of both the chiller and the auxiliary heating equipment The chiller satisfies the heating load and virtually eliminates the need for auxiliary heat during occupied hours Meanwhile natural cooling that is outdoor air introduced by an airside economizer satisfies only the portion of the cooling load that is not already handled by the chiller In this way the economizer balances the operation of the chiller with the perimeter heating loads That is the economizer only trims the excess cooling load that is not needed for heating purposes Refer to Figure 5 10 Figure 5 10 Effect o
165. CDS PRMOO1 EN Direct and indirect evaporative cooling Dedicated outdoor air systems A dedicated outdoorair system DOAS dedicated ventilation unit uses a Separate air handler to dehumidity cool heat and sometimes humidity the incoming outdoor air before delivering it to other HVAC units or directly to the occupied zones In either case the local HVAC units handle the zone cooling and heating loads Treating the outdoor air separately from recirculated return air makes it easy to verify sufficient ventilation airflow and enables enforcement of a maximum humidity limit in occupied Zones Figure 4 15 Dedicated outdoor air systems Sie eee ere dedicated 2 air handler oami SA RA RA SA SA SA conditioned air roe R local terminal units RA RA Application considerations m Always provide conditioned air that is drier than the air in the space This practice minimizes the cooling capacity required from the local HVAC terminals and adequately controls the indoor relative humidity without additional zone level dehumidification enhancements m Deliver cold conditioned air whenever possible and use recovered energy to reheat during mild weather Providing cold conditioned air from the DOAS minimizes the cooling loads at the local HVAC terminals During mild weather spring and fall modulate the amount of recovered energy used by the DOAS for reheat only warm the conditioned air enough to minimize inefficient re
166. Configurstion evedable 100 avaisi VIECI ooir cod Heating col im Emin IEEE Selector Oper Chedieeabed 14 Create Systems Dedicated Ventilation Deise Ventilation Locations Vosioble Volume Plehest I Min Flow Delak mind method Epira Tapy fat Chew Picard 3 l Note For additional information related to the other Control Methods press the F1 key and click Control Method Fum ude Desk Abemnatve System description fan and DOAU x Variable Volume Fiehest 30 Min Flow Detout Configuration Oehm preety o Cool Heat Control method Optence Supply Aa Dew Port Cooling Heating Design Setponts Cooling Hesting Setpoint Lasts Cooling supply ar dybu SF S air chy bu high im Heating acc dyb O pl Supp a chy bub kow im Couling supply ar dew point E 4 Cooling SA dew point high im 55 F Cooling SA daw pout kow imi fs Dedicated Vertilation Schedules Dedicated Ventilation Locations Cooling cod Avate 100 Deck Rerun Dudo Deck Heatrg col avvesatle 100 Level Sytem Optional favn o dation lan Avaldis 100 If the ventilation air is to be precooled the ceuxn s Create Systems Dedicated Ventilation Abemnative Syshem description fan and DOAU 7 Oehuencdty Ipncery or Cool Hew Configuration Cooling Heating Design Setpowts Coding supply ar deybub 5 1 Heatry supply a dy bu fea F Couling supply ar dew pont F Dedicated
167. DS PRM001 EN Calculation phases Figure 2 1 illustrates the relationship between the four calculation phases of the TRACE 700 program It also summarizes the type of information you must provide at each phase the kind of results to expect from each phase and where data from the TRACE 700 libraries is used Figure 2 1 Functional organization of TRACE 700 Your entries Building description m Location m Zones m Design data System description m Types m Economizer E Ventilation dedicated outdoor air m Energy management and building automation options Equipment description m Types m Pump heads motor efficiencies m Process loads Economic parameters m Mortgage life Utility rates Financial factors First cost _ E E m Maintenance cost CDS PRMOO1 EN e TRACE 700 User s Manual TRACE 700 Calculation results Program calculations Program database Peak and hourly loads by zone LOAD DESIGN PHASE LIBRARIES WEATHER SCHEDULES CONSTRUCTION TYPES AND SO FORTH Airflow and supply air dry bulb by zone SYSTEM SIMULATION PHASE Equipment loads by system by hour PLANT EQUIPMENT SIMULATION PHASE EQUIPMENT LIBRARY PERFORMANCE DATA Energy consumption by source ECONOMIC ANALYSIS PHASE RATE STRUCTURE LIBRARY Economic comparison of alternatives Program Overview 2 3 Calculation phases TIP In TRACE 700 libraries represent the
168. Demand Limting Protes Amiay coolo Cod hanes to piorar F Eie OO R se sins uae as gang eee 0 COS sneer nine ine wr Smary Srem p Adwy un I Ausdhary heating col Ace ate Ane Pamay Sy a Doph Ae Reiet FF Amdy tan o fore eer Selection She Mam levee _ Sox aA System i ert Verkar O versate F Une mron doina oude an reset Anio f Sm ot renee reres versien D amia Supply s DO cooing at otide a00 Schodde Avsistis 500 deroen Suoy 08 cooing hgh T a tte oe 08 Thee haki represent the combned sesetance of the carpet ji aast and the named foa panei and should NOT mchacte ary ae iin sentence There condo are ignored unter the auskey cig a Ng cod Capacity ovemdes are Gofimed on the Ceste Spoteme Heating Cod Overcton screen D Create Systems Fan Overrides Abenative 1 System depcription izne System 1 gt Single Zone Fanoxing schedde No fan cycing z Avedable 100 Aveiable 100 TRACE 700 User s Manual e CDS PRMOO01 EN Humidification Some buildings require humidification to provide a comfortable healthy environment and help protect computing equipment and furnishings Depending on the climate maintaining a relative humidity of at least 30 percent may require the addition of moisture In commercial applications with central ai handling systems this can be accomplished by adding a humidifier to the air handler Of the types available ASHRAE encourages the use of steam rather than wetted
169. Design Options 4 51 Dedicated outdoor air systems Alemetre 1 Syshem description WSHP and DOAU Water Source Haat Pump 1 Start by selecting Water source heat pump as the system type VAV wF coed Flow Sha Hesting Vertiahon acd Hasr 2 On the Dedicated OA Baen rea JW DE F tab select the type of 2 Contigastion Cehi iFern Heu z Contolmathod Fondse dedicated ventilation unit CooingHesing Design Setpcints CocingHesing Setpoint Lists to be modeled In this example the dedicated sche el ihn a ventilation unit will supply Cooling SA dew point ow le F low dew point air Deiosed Verdim Leoetons reheated to a room avise noon Deck Ronad Dek x neutral dry bulb in cooling opan n tl Symen O g mode and air at a specific dry bulb in heating mode ee o meo Therefore Dehumidify and Reheat Heat will None no dedicated ventilation unit be selected Cool heat a dedicated ventilation unit is used to cool the outdoor air to the userinput cooling dry bulb during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season Dehumidify priority or Cool Heat a dedicated ventilation unit is used to dehumidify the outdoor air to the userinput cooling dew point not reheated during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season Dehumidify and Reheat Heat a dedicated ventilation unit is used to dehumi
170. Doscripion Ensing Tower wih VFD 30 Comment Far cocira toner with 2 gpm ton New wELIL ITT a w Fi se ELIT Te lon E TEL TIT D Pot f FLIII TIAL E EHH S2nREP4Enn0 gt E E E oA R PE E EE A PA co wa waPaenwHeaenn ss ww of Full Load Cooling and Heating Plants Low flow chilled water systems 3 35 continued from page 35 a new unloading curve and assign it to the cooling tower Refer to Creating equipment and unloading curves on page 6 143 Be sure to save the cooling tower before proceeding 7 iS In the Cooling Equipment library copy an existing chiller Use 3 stage centrifugal for this example Rename the new chiller and add comments if desired 8 Increase the full load energy rate of the chiller to reflect the additional lift required from the compressor Obtain the new energy rate from a chiller selection 9 Select the variable volume pump created in Steps 1 2 for the condenserwater loop Note To model a low flow design that uses a variable volume condenser pump disable ambient relief Refer o Condenser water reset on page 5 26 10Choose the cooling tower created in Steps 3 6 as the heat rejection type Then save the chiller definition f When finished return to the TRACE 700 project and use the newly created chiller to define the cooling plant 3 36 Cooling and Heating Plants Low flow chilled water systems pay fW ater cocled dh
171. E Copy Alermatine Project Narkpilor Tephi ZERE py Edi Actions Vies Options Ubrares Templites Alernalives fop Window Era n SR Oe KReSKS BS FG 2 Plats System Assugrmerts No uy ratet Gefined OS Ted Caitulate and View Fetus 02 13 2001 0235 PM Beraject Information ip Naming the new alternative is not a required step but naming the alternatives makes the file easier to use and or edit In this example Alternative 2 has been named Central AHU TRACE 700 User s Manual e CDS PRMOO01 EN 3 Right click any section of Alternative 2 On the list that appears click the section to be Created new for this example click Systems Select Create new systems for this alternative and click OK Note The list can also be displayed by clicking Alternatives Setup 4 The Systems for Alternative 2 are now empty To input the new systems data double click Create Systems for Alternative 2 to display the Create Systems window and enter the new data Note The Create Systems window can also be displayed by clicking Alternative 2 and then clicking Create Systems After the new systems data has been input and the rooms have been assigned to the system Alternative 2 can be calculated CDS PRMOO0O1 EN TRACE 700 User s Manual The appropriate sections of the new alternative need to be changed from Use to Create based on or Create new In this example the Airside Systems s
172. E installed cost m inflation rate E maintenance cost E income tax rate E utility rate structures mM depreciation E cost of capital E study life E interest rate E recurring costs 2 18 Program Overview TRACE 700 User s Manual e CDS PRMO01 EN Performing basic tasks Figure 2 14 Define economics Project Tree view Project Tree View Project Navigator view D Promi Informaters E MT Aheraive O Uy Rates t Lie Cycle Costs A Erag Mone E Bc Systema zones and moms fo Ys ES Classroom 101 GEN Csssro0m 102 Depro Whe m Yi of oan TT E I 8 i ES Room 100 Administration Percent naad i z E Room 110 Tech Shep BB Room 111 Mute Room Depreciation tas Nee E Catetons amp fe Cranes Doti bailiran Laces foo x E Cissa 1235 E G FPVAV Classrooms Entries in the Economics Information OG Fan Coki Hals Storage f Mat Plants and oquiement a section apply to all of the alternatives defined within a project and are only editable from Alternative 1 a Project Tree view Project Tree View Ariy Equprendincdaied cod fl Revenue panal fp k H Year marieneren egansa 0 fs Buking mea vemide F274 Duling capacity ovemde tae LETS STEN 2 E Clattroom 103 n E Croon 108 irigi a targas wath oll uber fede Rate 5 Room 100 Administration Litiy z Delete Fighe E Room 110 Tech Shop EB Roo
173. Fan cycling In terms of energy consumption constant volume CV systems are costly Comfort is maintained by modulating temperature rather than the amount of air delivered Consequently the fans run continuously delivering design full load airflow even at part load conditions For CV systems that use many small fans rather than a few large ones fan cycling can provide one of the economic benefits normally attributed to variable volume systems reducing energy consumption by moving less air Figure 5 2 Fan cycling 100 This chart represents the cycle with occupancy fan cycling schedule The fan cycles on and off with loads during unoccupied hours defined in TRACE 700 as less than or equal to 5 percent of design occupancy 80 60 fan cycles fan 40 cycles building occupancy of design No D O 5 p m midnight 1 aiie 11 a m 2pm gpm midnight Application considerations m A building automation system BAS is required to implement fan cycling To ensure occupant comfort the BAS should automatically override fan cycling if the temperature in the space is outside the accepted range m Cycling increases the number of fan starts which accelerates wear and increases maintenance costs Avoid cycling fans with motors larger than 20 hp m Fan cycling is only an option for CV systems and for VAV systems with minimum stops Sample scenario A constant volume fan is scheduled to operate continuou
174. H Sanib j hath Aki hahaa Later 0 ts Ea Lagha Type Fhceeecent hung bein cola TOES bead be apace Heat Gent fa wah Mrcelortest kuk Sichechuls Cooling Cindy ferri TRACE 700 User s Manual e CDS PRM001 EN Figure 2 9 Create rooms As Figure 2 8 suggests each room template is used to group the four other templates together Consider using templates to streamline data entry Note Global templates are stored in the TRACE 700 database and are available to any project Project templates become part of the project TRC file For additional information regarding how to use templates refer to Using templates on page 6 125 Create rooms Remember that the TRACE 700 program defines a room as the smallest space for which it can calculate heating and cooling loads Room attributes include construction design airflows thermostat settings and sources of heat people lights and equipment If the building contains many similar rooms use templates to save time Before entering information about the rooms decide how detailed your analysis results should be For simple building designs or when a close estimate of the design loads is sufficient refer to Quick building inputs via the New File Wizard on page 6 110 For complex building designs or when accuracy is critical provide as much information as you can on each tab of the Create Rooms window Project Navigator view E e ce
175. IRFLOWS m Supply Air 1000 cfm Cooling Vent 700 m Infiltration 50 cfm a ae ace Min Stopi Fh m Room Exhaust 0 cfm Return 1 050 Exhaust 250 Rm Exh Auil Based on these inputs TRACE 700 will calculate exhaust air ventilation infiltration room exhaust 200 50 0 250 cfm return air supply air infiltration room exhaust 1000 50 0 1050 cfm Scenario 3 Infiltration with room exhaust less than or equal to the sum of ventilation and infiltration m Ventilation 200 cfm AIRFLOWS m Supply Air 1000 cfm Cooling Went 200 m Infiltration 50 cfm ase ncn Min Stop Rh mM Room Exhaust 250 cfm Return 800 Exhaust Rm Exh z250 Axil i 6 62 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Balancing airflows Based on these inputs TRACE 700 will calculate exhaust air ventilation infiltration room exhaust 200 50 250 Ocfm return air supply air infiltration room exhaust 1000 50 250 800 cfm Scenario 4 Infiltration with room exhaust greater than the sum of ventilation and infiltration Ventilation 200 cfm AIRFLOVWS Supply Air 1000 cfm Cooling Heating Wert 700 200 i 40 40 Infiltration 50 cfm aaae 1o00 1 000 Min Stop Rth Room Exhaust 350 cfm Return e00 en Exhaust o i Rm Exh 740 240 Axil i Based on these inputs TRACE 700 will calculate exhaust air ventilation inf
176. Induction 4 pipe Induction VAV w Baseboard Skin Heating ChangeoverBypass VAV with Local Heat and VAV w Forced Flow Skin Heating system types have an auxiliary heating coil it is the secondary induction coil located in each room for those systems However it is possible to add an auxiliary coil to any of the other system types by specifying a capacity value units typically as 100 percent of Design Capacity This auxiliary coil is sized according to the skin envelope load In addition this auxiliary heating coll can only operate during the non summer period months as defined on the Load Parameters screen Refer to online Help for additional details Load Design and Energy 6 14 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes m Some of the coils in the systems have been zeroed out For most cases this is strongly recommended against For example if either the reheat coil or the main coil is zeroed out in a VAV system the design and energy analysis calculations will be incorrect In this system reheat and main heating are actually the same physical coil Please refer to the System Type Characteristics section of the Help file for additional information related to coil sizing and location Load Design and Energy M Schedules have been entered for the coils For most cases this is strongly recommended against The default schedules need to be used in order for the coils to operate
177. Library Me ea pee ta am we TRALEE 700 CACDS TRACE 700 Projects TOO UTILITY TRE Fle Edt Anora View Options Libearies Templates Alernatives Setup Window Help lee SR er kRAeetevis SFR HB W Economics Ademvstive Eqapmertinuskedcon 5 srr z Yea mantenancemperne 5 tron a Reverse penaity fo fs Buking aea ovemide 78150 i id cr 16 Compary Northem Tine of Day 16 Uy Tlactic consumption lt kisen Do z Time of day Exargte TOO 16 AddShonal fest coat Utility Rote Northem Time of Day Electa demand Northern Time of Day Gas wa R z omme ee Depe iie Laors Yes You cont a reuned ow vey pas Fi e Sample Calculation Assuming that 6 000 kWh are consumed during January 3 500 kWh on peak and 2 500 kWh off peak the charges from the utility company would be as follows Customer charge 14 00 On peak usage charges 3 500 kWh x 0 065 kWh 22750 E On peak fuel adjustment charge 3 500 kWh x 0 01 kWh 35 00 TRACE 700 User s Manual e CDS PRM001 EN m otal on peak charges for consumption 14 22750 35 00 276 50 m Off peak usage charges 2500 kWh x 0 040 kWh 100 00 E Off oeak fuel adjustment charge 2500 kWh x 0 01 kWh 25 00 E otal off peak charges for consumption 100 00 25 00 125 00 Assume that 100 kW is the maximum demand calculated for the previous 11 months that 80 kW is the maximum on peak demand and 60 kW is the maximu
178. Over undersizing on cooling for a system with cooling supply air dry bulb specified by the user and a ventilation rate greater than the supply airflow needed to condition the space Room 1 E Cooling Os 11 000 Btu calculated by TRACE 700 based on heat gains E Ventilation cfm 600 cfm input by the user E Cooling Ts 55 F input by the user 6 58 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Oversizing and undersizing Required supply airflow to condition the space 11 000 1 1x SAx 75 55 SA 500 cfm Because the userinput ventilation rate is larger than the airflow required to cool the space TRACE 700 will use the ventilation rate as the supply airflow for the space In this scenario the over undersizing on cooling would be over undersizing 1 1 x 600 x 75 55 11 000 2 200 Btu This would indicate overcooling of 2 200 Btu because the space would need only 500 cfm at a supply air dry bulb of 55 F to properly condition the space Note If the system selected has the ability to reheat at the terminal device this is the amount of reheat that would be done at cooling design To minimize the overcooling remove the cooling supply air dry bulb and allow the program to calculate the value Summary points and additional items 1 For cooling design reports a a positive value denotes overcooling or oversizing of the cooling coil b anegative value denotes underc
179. P Single Zone System 5 Packaged VAV with Reheat Variable Volume Reheat 30 Min Flow Default System 6 Packaged VAV with PFP Boxes Parallel Fan Powered VAV System 7 VAV with Reheat Variable Volume Reheat 80 Min Flow Default System 8 VAV with PFP Boxes Parallel Fan Powered VAV Note Applying the Appendix G baseline system requirements may be confusing Refer to section G3 1 1 and Table G3 1 1A to include notes in ASHRAE 90 1 2007 plus the ASHRAE 90 1 2007 User s Manual prior to selecting the appropriate system for selection criteria exceptions and number of baseline systems required The number of rooms and zones assigned to a system in TRACE is critical to properly modeling the proposed and baseline alternatives Fully understanding this is essential System requirements Appendix G and the mandatory requirements found in Section 6 of ASHRAE 90 1 2007 set rules for determining whether various ECMs will be employed in the baseline building Do not assume your baseline building does not include these items Common control strategies are listed in the following table along with references CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 91 Modeling for LEED Note This is not a complete list ASHRAE 90 1 2007 is the primary source for determining if these or other control strategies are required in the baseline model TRACE User s Manual page or ASHRAE Standard loc
180. PCW x 12 000 Btu hr ton 6 000 000 Btu 6 000 000 Btu 6 000 000 Btu 1 COP of PCW A COP of 1 0 indicates that for each Btu of purchased chilled water consumed a Btu of cooling is provided Note Inputting a COP greater than 1 for purchased chilled water will cause an underestimation of the amount of purchased chilled water consumed by the building For example if a COP of 2 is used for purchased chilled water then for every therm of purchased chilled water consumed 2 therms of cooling will be provided Q Is the Cooling Energy Rate Cooling Equipment tab of Create Plants determined at the design condenser temperature Does it change at off design conditions A The Cooling Energy Rate efficiency rate of the compressor represents the energy consumption of the compressor at cooling design conditions To calculate the hourly energy consumption for the compressor TRACE 700 utilizes a primary unloading curve to account for changes in load determined based on a constant entering condenserwater temperature an ambient relief curve to account for changes in condenserwater temperatures water cooled equipment or outside air dry bulb temperatures ai cooled equipment and the design cooling energy rate For increased accuracy a capacity correction curve 6 34 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Frequently asked questions can also be included in the calculation to account for changes in ca
181. Phris wd equpmerd lias Cocting plants la Cookery plat 001 SE Waeroa e amp Cortisol ll Hosting ploris US Heating plant 002 Bote 001 Equpiant Category ied Project Tree view EHR Wiater cooked chiber 001 Fiesty plants Eia Hasir plani D 6 Rede On To create a cooling or heating plant drag the desired equipment Delete to the appropriate plant icon Project Navigator view EW Conley terest P Conderie nate pune Gi Pomay chilled eater pure pissing Egunan Babe Unip Hist Antes tag in Figure 2 12 the program models many types of cooling and heating equipment including air cooled chiller air cooled unitary air conditioner watercooled chiller watercooled unitary air conditioner boiler purchased chilled water a a a a water source heat pump a a purchased hot water a air to air heat pump alls electric resistance heat gas fired heat exchanger air cooled condenser cooling tower pump thermal storage purchased district steam cogeneration free cooling Adding HVAC equipment to a project is a matter of selecting the desired cooling and heating equipment as well as auxiliary When you select an equipment category the program automatically adds the appropriate auxiliary equipment pumps for example Program Overview Performing basic tasks 2 16 components such as pumps and cooling
182. RACE 700 User s Manual System Design Options 4 21 Fixed plate heat exchanger In Figure 4 9 which shows dedicated ventilation systems sensible heat recovery is often used to reheat the dehumiditied outdoor air Insets A and C or to precondition the outdoor air Insets B and C Insets A and C are typically used with systems that deliver dehumiditied outdoor air at a neutral dry bulb temperature Figure 4 9 Dedicated ventilation arrangements EA OA 4 22 Inset A parallel recovery stream to stream System Design Options SA EA SA OA Inset B parallel recovery stream to stream SA OA Inset C series transfer upstream to downstream Each of the arrangements in Figure 4 8 and Figure 4 9 can be modeled using TRACE 700 However only the arrangement shown in Figure 4 8 Inset A will be covered in this discussion of fixed plate heat exchanger energy recovery For arrangements other than this one select the appropriate energy recovery configuration similar to step 1 in this example and refer to the following Figure 4 8 for Inset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 for Inset C refer to steps 1 through 6 in Heat pipe on page 4 27 TRACE 700 User s Manual e CDS PRMOO1 EN Fixed plate heat exchanger To model the fixed plate heat exchanger scenario 1 After defining the system select the desired airto air energy recovery transfer type which d
183. SIR ENT 7 i Methods press the F1 key and dedicated ventilation a click Control Method heating coil heats the aeaea outdoor air to heating Covingesd avien OO Perakas supply air dry bulb FE eee Optimize SADB will be used Tac Gfore Dedkeoted on Terehia CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 63 Dedicated outdoor air systems 4 Input the Cooling and Heating Design Setpoints In this scenario 55 F should be input for the cooling supply air dew point 55 F for the supply air dry bulb low limit and 70 F for the supply air dry bulb high limit 5 Select the schedule for the coils and fan in the dedicated outdoorair unit Note If a custom schedule is created for the fan or coils it is recommended to use values of 0 percent for hours off and 100 percent for hours available to run to avoid confusion 6 Select the dedicated ventilation deck location This tells TRACE 700 where to supply the preconditioned outdoor air For this scenario the outdoor air will be delivered directly to the spaces As a result Room Direct will be selected 4 64 System Design Options W Create Systems Dedicated Yentilation Akamara System depcription Fan Cols and DOAJ Fan Col Configuration Dsehaumedity aed chest Heat Contra rsthod Epirus Supply tin Dry Bul Coleg Heating Daig Setpoint Coring Heating eani Limite Cooling suppi air dey bulky F Sippy ai dy bulb high im
184. Slat End Detenption cana W amp 2 Morh Harvwary December Cancel Simdan ype Reduced paar C Filyos z Comenents Enable manno wamp betereen Sam and occupancy al 7 an January December Sahaday to Sunday Dal Defiriion Cony Derion Schedule Definition Saul Ered Marth arua December TA EE TRACE 700 schedules define timetables for four day types Cooling design Weekday Saturday and Sunday The definitions within each schedule must account for all four day types Refer to Create schedules on page 2 19 For more information refer to online Help System Control Strategies Morning warm up for dual fuel applications 5 21 With the Schedule library still open select Equipment operation from the Schedule type list to create schedules that describe when each heat source is available 4 Create a new schedule with two definitions to describe when the gas fired furnace in the rooftop air conditioner can operate m On weekdays during morning warm up 5 a m to 7 a m and at night after occupancy ends 8 p m E On weekends throughout the day 5 Create a new schedule that describes when the electric heating coils can operate m On weekdays during occupancy 7 a m to 8 p m but not on weekends f Return to the TRACE 700 project to assign the new Thermostat and Equipment operation schedules 6 In either the Create Rooms or the Create Templates section for each room choos
185. System Control Strategies 5 49 Duty cycling Supply air temperature reset Supply air temperature reset is a control scheme that allows an airside system to modulate the supply air temperature based on outside air temperature worst case room demand or a combination of the two When enabled the temperature of supply air is increased which allows for reduced compressor energy or reheat energy but also increases fan energy in a VAV system When supply air temperature reset is based on outside air temperature the supply air temperature can be increased as the outside air temperature decreases allowing for more economizer operation This is done in a linear fashion as shown in Figure 5 1c Figure 5 13 Supply air temperature reset based on outside air tem perature 62 61 supply air temperature setpoint F 54 40 50 60 70 80 90 outdoor dry bulb temperature F Supply air temperature reset can also be based on the worst case space load demands If the worst case space does not require conditioned air at the design supply air temperature the temperature can be reset upward 5 50 System Control Strategies TRACE 700 User s Manual e CDS PRM001 EN Supply air temperature reset The two individual strategies can also be combined so that the supply air temperature is reset based on both outside air temperature and worst case room Figure 5 14 Figure 5 14 Supply air temperature reset based on worst case room and
186. TCE h m h V n E Mehandi gt Fh Edi Aiha Vew Opi arly f e is LD ee eer Oe Rig be aR Ff input Click OK ee peeo Project Navigator 10 The five sections of 9 Ce Chiller Plant Analyzer should appear IFI Calculate and View Results OG 2002 TEM AM From here clicking the icons will allow viewing and editing of the individual sections Enter Project Information general information can be entered to identify the project This information is optional and is used for identification purposes only It will be printed on the Economic Summary report Select Weather Information allows the user to reselect the weather location or to override the design temperatures to make the weather profiles more or less severe TI reate Plants Pie Abeomative 1 faa c AEE A tt aN 44 77 Ancooked Arcoked Waterco Warco Heating plants chiles unite chiles unite Mas Heating plare 002 m Wam Boles ss Elect Garfred Create Plants allows the user bource he feeutance hee exc to edit the cooling and heating i 2 F amp plants selected in step 3 As cocied Cocke Purge Thermal Condenser tomer thotage To stag equement dag the deteed equpment calegory lo the cori zahon bee Configuation Cotano ing Equpmert D create Plants alz Abemeative 1 Cooling plant Coning plant 001 Heat rajecton type Cakra tever wih VFD z Eqipnert tog fwater cooked chier 007 0 x Equipment catego Watercoced ches Y T
187. TRAC EOOOE F Complead Tories F KacwProfilers F TRACE E Geen plata d_Tossria hak Tiig E Datania are kil Trini Pr Biaid Cin Alberaia xj Fone SREE p o EES CACDSATRACE 70NPqcts ASHRAE 621RC42 TRC Ceai C Ho Standard CS Pg ree Mote HIE oe aimee ee ee eee a ae gE pach a unique description belies proceeding Lede a eeded bacwan Won aries nvdhach ttn A kibai hera iayy real makeh ha cider r lha asad on fe we IRACE 700 CACDS TRACE TOD Projects Propect tr Fle Eda Amoras View pioa Libeuries Templates Abernatives Seng Window halip lSe ho gt R ar kcaecteve STAR TRANE Project Navigator CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 179 Creating a new file based on an existing file How to sort output TRACE 700 creates Checksums output reports at three different levels system zone and room It is often desirable to view only certain room and or system output reports 1 After a file has been ST q A zj calculated go to the kiana arenaer 2 Pork View Results section of Summary System m TRACE 700 I Tite page F Design sition Croat 7 Synem checksum l Design capacity Pret Setup 2 Select the desired ee I ine Doe T Room checkit Checksums report s F Dosign cooing oad T Synem component selection 3 This will activate the Options button on the Pocteometc MMM i y i Abemnatree akemative 1 right hand side of the l Zena x ja S
188. Teunlerence type Her meran eperme oeoa maen type tae new approach O Pumamammaeemeoen 7 temperature here TRACE 700 User s Manual e CDS PRM001 EN Plate and frame free cooling llas To model a cooling plant that includes a plate and frame heat exchanger 1 CDS PRM001 EN TRACE 700 User s Manual Select the desired equipment type For this example pick one of the centrifugal chillers from the water cooled chiller category Enter the full load consumption for each pump Click Controls and choose one of the plate and frame options as the free cooling type For a cooling plant with multiple chillers be sure to specify the free cooling option for each chiller Ahana 1 Coning plant Eira mia Hean Equpmertiag watercocledchler 001 Typa Cern hrvata ine Cert Cheer Equipment catego viteae ce Howi anben et babati Eames Tias Careu A e Seguenongyea sr o y io Type a sowie OE Cooling as xj Plant description Cooling plant O01 Eicpapareerd Laj Vat beroi chiller 001 Cancel Plate amp frame series uses the p Fr Cesira Type Piste L larma heat exchanger to supplement w e a co mechanical cooling Pump ETT E i mote P Plate amp frame uses the heat ooo E a exchanger instead of mechanical Masehi wamne fo F cooling but only if ambient a 7 Evapa pompon He conditions permit The heat ium pe exchanger only operates if it Can Fiet ssndemisihas Haat re
189. The plenum height is also used to decide if the roof conduction and solar heat gain loads are to be directed into the plenum or directly into the room Refer to F1 Help for additional details Note Entering a plenum height does not tell the program if the system has a ducted return or a plenum return The return air path can only be selected on the Advanced button in Create Systems Q Why does purchased chilled water only have a COP of 1 when a chiller has a COP of 6 A The COP Coefficient of Performance is a dimensionless term used to report the efficiency of cooling and heating equipment and systems For cooling equipment COP can be defined as the ratio of the rate of heat removal to the rate of energy input to the compressor Note Both sides of the ratio must use the same units Stated another way _ Cooling provided COP eS Energy used to provide cooling Example 1 Chiller Cooling Plant COP To calculate the COP of a chiller providing 500 tons of cooling for one hour at design conditions with an efficiency of 0 55 kW ton the following calculation would be used 500 tons x 0 55 kW ton x 1 hour 275 kWh CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 31 Frequently asked questions Therefore to produce 500 ton hours of cooling the chiller consumed 275 kWh of electricity 12 000 Btu hr 1 ton of cooling 1kW 3 413 Btu hr Cooling provided 500 ton hours x 12 000 Btu hr ton
190. Tile On the File menu click New then TRACE 700 then enter a name for the file Ux and click Open TRACES 700 Fie Adora Litraries Help Oe B Z ASHRAE 62TRC_42 TRC F Complered TwornalBAK TRC T EX2I40 42 7 z Usa Zoning to 2 ecan mistakes So J Onn Note Verify that the latest FF compare tac F energy Tutorial ee FJessosr F Complered LEvmorial42 me F Energy Tuvorial_42 1r0 F BGNAG lt version of TRACE 700 is Z Conpiesaa_Tiunceist tre T Loa TAC T Dagom FT Completed Tutorial 42 TRC T EXINROA TRC FT bu40 Ar installed before beginning j this process Updates can be downloaded by going to Fis ctlypm TRACE 700 Fie oa a He the Help menu clicking a Trane on the Web and clicking Check for Updates no TRACES 700 CACOS TRACETOO Projects EX4_obXML tre or by visiting the Download ee eer Etaio amp Oat Center at s www tranecds com 2 On the File list click Import gbXML 3 Navigate to the xml file that was created during the export from ABS 2005 and click Open Note If errors occur during the import process please Feno Mineo 3 install the latest MSXML O cancun from Microsoft from h ttp f f Import fron gal xj support microsoft com p n 4L E default aspx scid fh EN FF Misesa kade E Ventilation afo US sp FF Design tamparstures 4 Select the desired information to import from the gbXML file and click OK CDS PRMOO01 EN TRACE 700
191. To model time based sequences that vary by the day of the week or with holidays use the Library lemplate Editors program to create the desired operating schedules Then assign the appropriate operating schedule to each piece of equipment For an example refer to Morning warm up for dual fuel applications on page 5 20 Abemative 1 Equpmert Category Configuration n Cookers parts A wm of amp ie aes 2 A r A an Chiles 1 elec contihapal Aacooed Arcod Waterco Water lt o che unay chiller unter Chiles 2 deect fred absorption Plat Wierd Heating plants lias Heating pilare 002 New Cig Plot 6 6 2B W ater Boer Electr Gsrfred amp amp F As cocied Cocker Purge Thermad Corant tho ERE i i ce OD Chiles 1 elec corinhugal Oha 2 direct fred abso Sequence 001 2 Chaer 2 ideect teed abao Ohler elec centitussl Sequence O02 Bare al sequencer on Teme 3 ee ake tel eels ea ee Begin and end with midnight to define an entire 24 hour period TRACE 700 User s Manual e CDS PRMOO01 EN Switchover control for chiller plants Thermal energy storage Adding thermal energy storage to an HVAC system can reduce energy costs associated with comfort cooling by shifting equipment operation trom high to low cost times of day Typically this practice is only economically feasible where the local utility company offers incentives in the form of rate structures
192. Total capacity of the cooling coll CDS PRMOO1 EN TRACE 700 User s Manual BP E Prods Mer Pam Wow HD FEF hob Hakl AE laici TAT Re ale Le at wid fh Haigh ria He ia F Maite Produchy In Upe F Cening cna E aia Note The TRACE 700 Output Interpretation Manual recommends the following For a cooling coil the following data should be used the capacity of the coil airflow at time of coil peak and entering air conditions Desg Options Religecant Options Gere User Detined AN Freids double click ihe field and the program will tell you what data should be removed to allow input into the field Advanced Usage and General Modeling Tips 6 75 Selecting a chilled water cooling coil using TRACE 700 output 5 Enter the calculated nominal coil height and finned length this should eliminate the last of the required red inputs Click Run at the top of the screen 6 In this case the selection program tells you that no cooling coils meet the entered criteria 7 To find recommendations on what input criteria are causing problems and to find out how to make input adjustments so that a valid cooling coll selection can be obtained click Run Messages the question mark at the bottom of the screen If a specific ai handler size was selected in Step 3 the size of the coil may already have been determined However for this example where we are selecting a standalone shippin
193. User s Manual TRACE 700 Building Energy and Economic Analysis version 6 2 LIMITATIONS OF LIABILITY AND DISCLAIMERS The Trane Air Conditioning Economics TRACE 700 software is intended as a design and analysis tool to help designers optimize the design of the heating ventilating and air conditioning system based on energy utilization and life cycle cost Program accuracy is highly dependent on usersupplied data It is the user s responsibility to understand how the data entered affects program output and to understand that any predefined libraries are to be used only as guidelines for entering that data The calculation results and reports from this program are meant to aid the system designer and are not a substitute for design services judgment or experience TRANE IN PROVIDING THESE PROGRAMS ACCEPTS NO RESPONSIBILITY OR LIABILITY FOR THE SUITABILITY OF THE BUILDING AIR CONDITIONING SYSTEM IN PROVIDING PROPER TEMPERATURE CONTROL HUMIDITY CONTROL INFILTRATION AIR DISTRIBUTION AND QUIET OPERATION TRANE SHALL NOT BE LIABLE FOR ANY CLAIMS CAUSES OF ACTION OR DAMAGES ARISING OUT OF OR ALLEGED TO ARISE OUT OF THE USE OR INABILITY TO USE THE TRACE 700 PROGRAM UNDER NO CIRCUMSTANCES WILL TRANE BE LIABLE FOR ANY INCIDENTAL CONSEQUENTIAL OR SPECIAL DAMAGES REGARDLESS OF THE LEGAL THEORY ADVANCED Climatice Trane the Trane logo TRACE and Varilrac are registered trademarks and C D S and EarthWise are trademarks
194. User s Manual Advanced Usage and General Modeling Tips 6 183 gbXML import and export 5 Note any error messages that occur during the eet E PPE EE ope soe yp import process and click OK Be sure to verify the inputs that relate to the error messages in the TRACE 700 input file In this case ventilation airflows were input in two ways in the CAD file Therefore one of the methods was selected to 5 tL be used in the import Note Due to the gbXML import the vast majority of inputs for ne TRAC TOO CACOS TRACETOO Projects phil Example tine Pe EB i Yew Spiers Mewes Tends Menide Sei He Create Rooms will have been 6 Verify refine the inputs in Te eS Lheeceeteve SBC _ OO wtQt Pdoe i filled out during the import Create Rooms and or LeYRF Create Rooms Single Workshert use templates to make Abeenstive 1 Pr OPE ta ole ue Roomdescrption Las remas aMi 75 percent of the time that it changes In mass refer to Templates Length wiih takes to input a file is typically Using templates on Room Desa O Fhe fm OR fT spent in Create Rooms and page 6 125 for details on m a E 7 f ied Ea the gbXML import can reduce how templates work tax owe this time by more than two Cerir Pe Decpkn Leghji Haga Desin thirds aea fio jas jm pp Co ju 5 7 Add additional details to the airside systems in Create Systems Fedral kaiii Aalbert 8 Reassign the rooms to Pople fi Posie I Covert M26 empen
195. Verthston Schedules Cooling cod Avaliable 100 Hearo col Options avantatie 100 Selection Optors Dedicated outdoorair systems avekatle TKR H 5 Dedicated Ventilation Cooling Coil schedule defines the hours of available operation of the ventilation cooling coil The optional ventilation cooling coil is available for any hour that this schedule reads 1 percent or greater If the ventilation air is to be preheated the Dedicated Ventilation Heating Coil schedule defines the hours of available operation of the ventilation heating coil The optional ventilation heating coil is available for any hour that this schedule reads 1 percent or greater The Optional ventilation fan schedule defines the hours that the ventilation unit can Dedeated UA operate If the Optional ventilation fan schedule reads 1 percent or greater the fan is available that hour TRACE 700 User s Manual e CDS PRM001 EN 6 Select the dedicated ventilation deck location This tells TRACE 700 where to supply the preconditioned outdoor air For this scenario the outdoor air will be delivered to the mixing box of the VAV air handler As a result Return Outdoor Deck will be selected 7 Select the level of the ventilation deck location For this scenario one large dedicated ventilation unit will condition the outdoor air for all of the rooms assigned to the VAV airside system so the coils should be set
196. Weekday as the ending day type E Utilization schedules require you to define a schedule for the Heating design month The program uses it during the heating load design calculations of airflow and supply air dry bulb To define a 24 hour period use Midnight as the first start and Note For the heating design month schedule only include loads last end times that contribute significantly to the building heating load ventilation and infiltration for example but not internal loads such as those associated with occupancy and lights To exclude a load from the schedule enter 0 as the percentage exclude a scheduled load from energy calculations m When creating a Utilization schedule always start with January and end with December m For example to define a Utilization schedule for an event that starts in May and ends in September include January through e a April and October through December at zero percent m When adding start and end times to a schedule definition use Midnight as the first start time and the last end time The program will prompt you to correct periods that overlap Simulation methods To arrive at equipment loads and energy consumption the TRACE 700 program calculations are based on the simulation hours set for the project You can choose between two methods of calculation reduced year versus full year analysis refer to Figure 2 15 on page 2 23 CDS PRMOO1 EN TRACE 700 User s Man
197. a ia Hesmg pan 1 heat pure kap Ia Cora plant 2 Diecieeted D unti ia Hesting plant 2 Dedicated DA ura lll Cooling plant 1 hest pumpa RH Coig Suiten WSHP and MOAL BD Main Cosg Coa fl Pieating plant 1 heat pure lene BOE Heating System ASHP and DAU E Mar Heating Cod fl Costin plant 2 Diechosted DA unit RH Cosi Suntan WSHP and MOAL E Dpiiia Ventilation Cojing Col lk Meeting plant 2 ediad DA unt et Heating System ASHP and DAU Diiia Ventilation eating Cad System Design Options Dedicated outdoor air systems HP 4 55 4 56 System Design Options Table 4 7 Equipment types Cooling Equipment tab Heating Equipment tab Watersource heat water source HP gas fired hot water pump high efficiency boiler Aircooled unitary split system RAUC rooftop gas heat 20 ton scroll Scenario 3 A building is served by a VAV airhandling system on each floor A dedicated outdoorair unit delivers conditioned outdoor air to the intake of each air handler During the cooling season the dedicated outdoorair unit dehumidifies the outdoor air to 55 F dew point but does not reheat it During the heating season the dedicated unit heats the outdoor air to 68 F dry bulb In addition the system level controller polls the humidity sensors located in each room and resets the dew point leaving the dedicated outdoorair unit to prevent the relative humidity in the worst case room from rising above
198. a nut eue Wir Mather Piia Corgan rA OSTRA Ta AM Bae EP rem ptu CO S E S a O x es should open tt FesA sit Mo an 0s Farat E je Fetah G 4B 14Click Modify System Profiles on the Edit menu select either Edit Drag Hourly Demands or Edit Monthly Consumptions and click OK For inputting a known load profile ataystem Profiles Editing WEA select Edit Hourly Seo Phe coor hon bk shet tot th ay demara relies Demands fF Edt Hourly emanda 14 I Edi Monthy Consumphor C ou 6 120 Advanced Usage and General Modeling Tips Inputting an existing load profile Data Type Bare Utter Ordy Save Draw rs pm Date utlies not ceded Pps aon emmy or feos Uy We bose Varco ug Lar F Sucked C 0 F Chet P CD Componerts Cg amp Hig Col C Dond Conqumptorn TRACE 700 User s Manual e CDS PRMOO01 EN 15Read and follow the instructions listed on the next screen to open the load profile in a spreadsheet 16 he spreadsheet should have one column for cooling loads and one for heating loads Input the known load profile and save the changes Do not make changes to the headings or to any columns other than the cooling and heating values 17Save the file and close the spreadsheet program Click OK and close the TRACE 700 Visualizer 18Edit the inputs for the cooling and heating plants to accurately reflect your model and re
199. aaa T 2 14 ASSIGN FOOMS tO SYSTEMS cccc cece cececeecee seen eeenes 2 15 Create LATS seira T Te 2 15 Assign systems lO plants creer 2 17 DEMES CONOR IC Sista tec E A 2 18 Create schedules oct a A 2 19 General modeling MINES rarnana 2 25 CDS PRM001 EN TRACE 700 User s Manual Contents Chapter 3 Cooling and Heating Plants Decoupled chiller arrangeMent cccccecceseeeeeeeeeeeaeees 3 3 Parallel chiller arrangement cccccccceeeeeeeeeeeeeeueeesnees 3 7 Series Chiller arranGeMent cceccccecccccceeeeceeaeeeeeneeeanes 3 9 Variable primary flow chiller arrangement icce 3 13 Switchover control for chiller plants 3 17 Thermal Energy StOrage sea AE cece eeeeeeeneeenneees 3 21 OC Cee NC eee a eae eieeetees 3 28 Direct fired absorption Cooling accicxciacSi sees 3 31 Low flow chilled water SYSTEMS cccccsecceeeeceee essen ees 3 33 Purchased chilled WALCR ccctcveis rutiinesed wager ait tenhine tated 3 37 Purchased district steam and purchased district NOt water ec eeccseeeee cece eeeeeeenes 3 40 Plate and frame free cooling cccccceeeceeeeceee este esses 3 43 Refrigerant migration free COOLING ccccecceseeeeeeeeeeeees 3 46 Strainer cycle free Cooling fsscesvecsirecshti whats tectaceiewtees 3 48 Double bundle condenser heat recovery 3 50 Evaporative precooling of condenser aif 3 54 COOlING tower with VFD sareni Botheaete tad 3 57 Chiller toWer OPTIMIZATION
200. abaran ir baa earder haa Piau Leet ree Gescrption esar piant W a tt z Siingreelhed Block baredon dengn ordain O Sas Cesi Tape Nore kiua abian wot bulb aea wa amaaa The Plant Controls dialog Te ZEO 3 box contains the coraan entries that Thos essence configure the distribution pump Cooling and Heating Plants Decoupled chiller arrangement 3 5 Note In a decoupled piping E Miscellaneous Accessories Library alls arrangement the secondary Casy wae nao Unloading cuve voei va rarawa eo a See distribution pump runs ma a Varme Vol Coa Waie Pure whenever one or more of the ton chillers is operating To model faloa eneng 0000563 fwata 3 cay eee Etecmery this control characteristic ae Euan we library definitions for pumps avenced use with equipment as the control type Control type sets jy Use the Library Template the default operating l en Editors program to view the profile predefined pumps in the sot PALONG Miscellaneous Accessories library or create custom pumps On the Libraries menu select Equipment and then Misc Accessories 3 6 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMOO01 EN Decoupled chiller arrangement Parallel chiller arrangement To ensure uninterrupted cooling many chilled water plants are designed with at least two chillers even though a single chiller can often satisfy the system load Typically either of
201. ace the generic name for the equipment type with something more descriptive and add comments if desired Choose a variable flow pump for the condenser water loop To eliminate the effect of ambient relief for the condenser specify a minimum operating temperature that equals the design entering temperature Flow based condenser water reset Most of the watercooled chillers in the Cooling Equipment library are defined with constant flow condenser pumps The following example demonstrates how to model condenserwater reset that is controlled by varying the flow of water through the condenser nip x Fie View Opiom Windew Help COYaSSe Reel EES COMTAOSE P TRANE Coding category ater cocked chet Comments JOME CENTRIFUGAL OMALER 170 600 TONS Equipenant ype Stage Certntugal 13 Cookng type Cerentupal paky categagy Pwister cooked chiy Comments Larson CHE 1H TONS ures arable few cord peret Exquaprreend bygas Dardihugal chabert ev ra irad ikre 3 Darca Coolngivpe Certtugal Changing the curve type to None will not disable ambient relief Instead use equal values for the design entering and minimum operating condenser temperatures E Cooling Equipment Options MEE Hite chilled wwen mand fo F Logd checking comin Ne Fuel stance Lite Fuel bape Electri Foe When finished return to the TRACE 700 project to add the newly created equipment to the cooling plant
202. ach other to fix the value for the cooling supply air dry bulb This is suggested because TRACE 700 cannot psychrometrically solve for the cooling supply air dry bulb when an energy recovery transfer device Is attached to the Return Outdoor deck Refer to Frequently asked questions on page 6 20 for the ramifications of inputting a cooling supply air dry bulb CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 7 Desiccant dehumidification Coil loop for exhaust air energy recovery alls Devices including total energy wheels and heat pipes other than the coil loop described here can exchange sensible and or latent heat for energy recovery 4 8 System Design Options An exhaust air energy recovery system can reduce utility costs by capturing and using energy that would normally be lost to the exhaust air stream A coil loop can be applied either to the primary supply air system or to Independent systems such as the dedicated ventilation system that serves a laboratory The effectiveness of the coil loop typically ranges from 45 percent to 60 percent for recovering sensible heat Figure 4 2 illustrates how the coil loop works During the heating season Inset A heat extracted trom the exhaust air stream EA warms the air brought into the building Operation of the coil loop is limited to prevent the supply air temperature from exceeding the cooling set point This condition is most likely to occur on m
203. ackup r Heat Pspain electric resistance by Cooking plant TF A TAE Fi Concararara SCS wi selecting the plant and Eerie a E Hep tert wet bt iat t E clicking the Edit button Equipment ype E gt VAF Han Purp Mantia Spad Conga F Thamal Sirag wta Seqencnghee Sigh a 4 Select the cooling plant and a GH click on the Cooling CO EEE Equipment tab 5 Choose the VRF plant that best matches the target performance and operation There are two categories of plant available VRF Heat Pump and VRF Heat Note The VRF Heat Recovery option is able to recover heat from one VRF Recovery indoor unit and share it with other indoor units that are connected to the same refrigerant circuit TRACE assumes that heat can be recovered between all zones that are assigned to the system However heat recovery outdoor units are available only up to a certain capacity 20 tons as of this writing To accurately model VRF heat recovery the design capacity of all the indoor units zones assigned to the system should be no larger than the available capacity of the VRF Heat Recovery outdoor unit This might require the creation of several systems and several cooling plants 6 Specify Backup electric resistance as the backup heat source CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 83 Variable refrigerant flow system 7 On the Heating Equipment tab refine
204. al RE Dedicated 4 unk F eet Hesg plants da Bl Heating plant 1 bode Elie Gariad E H Gated boks racittence hes ilk Heating plant 2 decicosted O14 unit ener hanger fee Gasded heat ewchanges rootop i ar For cooling use air cooled chiller and an air cooled unitary For heating use boiler for the WSHP system and gas fired heat To nemp equpmeni crag Pe dened ouin excha nger TRACE 700 User s Manual e CDS PRM001 EN Dedicated outdoorair systems z2 Finally assign the coil loads of the air distribution system to the proper cooling and heating plants 13Drag each coil in the Unassigned Systems Coils pane to the appropriate plant in the Systems and Plants pane The illustration labeled After shows the completed assignments E Man Cooling Coa G Optional Vertiation Cooling Col OC Heating Spstem VRH and DOAL gt J Main Heating Coa E Achas Coa E Preheat Coa E Optional Vertilation Heating Cod Before Table 4 8 Equipment types Cooling Equipment tab Aircooled chiller Is Cockers plart 1 ae cooled chier ila Heating plant 1 bosa la Cocking plart 2 d dcated 04 un llas Heating plant 2 dedicated OA un New Coot Plant air cooled helical rotary chiller Eii Coig plant 1 se cocded chier EHE Canling Sytem WAH and DAL D Man Cooking Cod i lbs Hiei plar 1 phasi GRE Heating Synem WAH and DOSU E Mar Heating Cod New Hoot F Rehes Co E Pr
205. al Path Air Handler Split Dehumidification Unit m When the outdoor dew point is less than the current supply air dew point setpoint and the outdoor dry bulb temperature is greater than the cooling supply air dry bulb setpoint the outdoor air cooling coil will cool the entering outdoor air to the cooling supply air dry bulb setpoint The return air cooling or heating coll modulates to maintain the space temperature at setpoint m VWVhen the outdoor dew point is less than the current cooling supply air dew point setpoint and the outdoor dry bulb temperature is less than the cooling supply air dry bulb setpoint the outdoorair heating coil will heat the entering outdoor air to the heating supply air dry bulb setpoint If no heating coil exists in the outdoorair path input the heating supply air dry bulb colder than the winter outdoor design temperature The return air cooling or heating coil modulates to maintain the space temperature at setpoint This example will cover how to model the airdistribution system steps 1 8 model the cooling and heating equipment steps 9 11 and assign the loads from the coils to the equipment step 12 Alamate 1 Syshem descnption Dua Path Aw Harder Single Zone Ah 2m New w huchon a 4 1 Start by selecting Single Uden Dian d oe Zone as the system type San EF 2 m z A a Pack 2 Click Advanced and select or verify Draw Thru fan configurat
206. al zone YW rn wer a ai 5 La a zu x 1 th f Full Airficnw System Control Strategies Fan pressure optimization for VAV systems 5 13 Ventilation reset for VAV systems ANSI ASHRAE 62 Ventilation for Acceptable Indoor Air Quality is considered the standard of care for designing ventilation systems in commercial buildings That document details a prescriptive Ventilation Rate Procedure for compliance which relies on adequate dilution of space contaminants to achieve acceptable indoor air quality Two ventilation rates must be considered to successfully apply the Ventilation Rate Procedure In a multiple space system the minimum required ventilation rate for each space which can be determined from the type of occupancy and design population and the total system ventilation rate needed at the air handler which is defined by Equation 6 1 from ANSI ASHRAE 62 2001 Equation 6 1 takes credit for unused ventilation air returning from overventilated spaces reducing the total amount of outdoor airflow for the system Figure 5 5 Ventilation reset for VAV systems central air handler with controls E outdoor airflow measured and controlled mM outdoorair temperature M supply air temperature supply static pressure SA a VAV terminals with ay DDC controls M required ventilation Z E primary airflow communicating m calculated space building automation system ventilation fraction E total supply airfl
207. ally be allowed to calculate the supply airflows based on the input loads by selecting Main Supply units of To Be Calculated Load Design and Energy Note The VAV minimum airflow only applies to variable volume systems The VAV minimum airflow is ignored for constant volume systems m The entered VAV minimum stop may be too low for some rooms This can lead to spaces having a higher specified ventilation rate than the minimum airflow This will result in insufficient ventilation airflow in heating mode This typically leads to heating ventilation being different than cooling ventilation at the room and or the system level The Airflows section of the Room Checksums can be used to check for this condition Load Design and Energy Note In most VAV systems a zero for the VAV minimum will cause the box to close completely when the room calls for heating E The VAV minimum airflow schedule is not using the schedule Available 100 For most cases this will cause low airflows to the space and incorrect results The only time this schedule should be changed is for a VAV box with two minimum stop settings The VAV system may not operate properly if any other schedule is used and cooling and heating energy may be underestimated Load Design and Energy E Ihe airflows are not balanced in room s in which room exhaust is entered Airflows must be balanced at the space level for TRACE 700 to calculate the space energy balance properly Please
208. an Powered V Paralel F arrPoveered V pod Hig Cod on Pieru irdet Senet F an Powered VAV Tofan Dende Duct VAV arar Volume VW Paralel Fan Powered sae 1 Hig Col on Maang Box Outlet l zj This entry directs the program to calculate the Note For an optimally designed system several gn nu system level ventilation iterations of calculations may be required to find J airflow required for design optimal minimum stop positions when using by solving Equation 6 1 of AA 62 as the a N memhodology J ASHRAE Standard 62 2001 Refer to ASHRAE Standard 62 in the online Help 5 for additional information related to ASHRAE r During simulation STD 62 calculations z TRACE 700 calculates the Seana fey Waning The licks makadi rod ae cove Components of ths eysttem Changing Vertdshon deck locates Retar Odon Deck ata values Can Gastcaly atisct how 4 individual room ventilation fractions for each hour to the sythem operates Pleane make ure arrive at the hourly Other methods of controlling system level ventilation include ventilation airflow required m ASHRAE Std 62 which directs TRACE 700 to use Equation 6 1 to at the system level calculate the system level ventilation airflow required for design During simulation the system will attempt to introduce this amount of air whenever ventilation is needed E Sum Room OA Reqs which defines the system level ventilation requirement for design and for each hour of s
209. an only be used if the cooling capacity of the tower water is sufficient to meet the entire building load 3 46 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Refrigerant migration free cooling Nhs To model a chiller with refrigerant migration free cooling 1 Add the appropriate equipment category to the cooling plant For this example select water cooled chiller This is equivalent to dragging an equipment icon to a plant on the Configuration tab Replace the default equipment tag with a more descriptive name if desired Select the desired equipment type and full load consumption for each pump Click Controls and choose the appropriate option from the list of free cooling types in this case refrigerant migration Little if any free cooling capacity is available when the ambient wet bulb temperature exceeds 50 F Unlike the compressor which is off accessories such as pumps and cooling tower fans continue to operate in the conventional manner during the free cooling mode The cooling tower must be designed for winter operation Related reading Chilled Water Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRCO16 EN Sample scenario A water cooled centrifugal chiller is equipped for refrigerant migration free cooling When ambient conditions permit free cooling satisfies up to 40 percent of the design capacity of the chiller
210. ance characteristics different from the actual coil selected by the user CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 73 Selecting a DX unit using TRACE 700 output Selecting a chilled water cooling coil using TRACE 700 output 1 After calculating the TRACE 700 file there are several output reports that can be used to get the data required to select the cooling coil For the Variable Volume Reheat system used in this example the System Checksums report and the System Component Selection Summary report can be used This section discusses the steps for properly selecting chilled water cooling coils using the TRACE 700 output reports It will be assumed that no mistakes have been made in the modeling process and that all results are accurate for the building and systems Related reading Cooling Coil Heat Transfer Engineers Newsletter volume 31 number 1 Sample scenario The design team has decided to use an air handler with a chilled water coil The design data from TRACE 700 will need to be input into a selection program to find an appropriate cooling coil From these reports the Total Capacity Peak Airflow Entering Dry Bulb Entering Wet Bulb Leaving Dry Bulb and so forth can be taken where Total Capacity 91 5 Tons 1098 5 MBh Sensible Capacity 735 9 MBh Supply Airflow at Space Sensible Peak Load 26 333 cfm Supply Airflow at Cooling Coil Peak Load 24
211. anced for each system that will have outside air calculations based on Standard 62 1 5 Select the appropriate Standard 62 1 calculation System Design Options ASHRAE Standard 62 1 4 94 we reale Reson Airihi Alken 1 Agee sa briri brai ioscan Room decanter Clavie 101 tia aaen a tans gt hance Han gupphy Coning To be ealeuisied eee Vieni Apoy ASHRAE Sit 1202007 Yes Tyee Elannon lage Teh Peopbased 10 eip Arebered O12 emsan Schedule Vera Ebesi bikibi Type Hers Caeira p E dhangedtr E E dhangedtr Heating Scheschle avaisi Te Templates Fem Odne al Uriari Cie ait Patios Detaut Tos Deina ortt Deimas Single Sheet Rooms Floats yas brt Loach Aapdiay tue Cele To te eaea Heating Tote calculated Sad Bot T A Cig Ex Ceiling cl tupoy ceing rem 100 Hig Ez Cong neey gt orn FIO 20 o Ostech boved on arson vo Sxl DEW Hir DA mts C urre Feces ghana Plate p oo Schedule ivast 10005 E Cig Arik Schedles Enise OECEI Tyee Deiat 3 Note If the recirculation effectiveness is unknown select Default based on system type TRACE has a default value for each available airside system Abemnatree 1 System description VA Retest Classrouess Vanatle Volume Reheat 30 Min Flow Delak Twof an Double Duct VAY UFAD VAV w Baneboard Heating UFAD VAV w Farkssis
212. ann atectivercs at 75 ain EE 2 Indirect col schedule OF 1 Latent Fme benni dia ental Cooing effeciver ss at 100 akw 0 Type Fes pia Cooling effectivermss at 75 awie 0 Supside deck Retuen c Heating eliectiverets at 100 sifiow 0 x Extriade deck Rean x Schedule Avalatie Additional Items When adding a fixed plate heat exchanger to an airside system it is recommended that the minimum and maximum cooling supply air dry bulbs be set equal to each other to fix the value for the cooling supply air dry bulb This is suggested because TRACE 700 cannot psychrometrically solve for the cooling supply air dry bulb when an energy recovery device is attached to the Return Outdoor deck Please read the FAQ and Oversizing and Undersizing sections of the manual for the ramifications of fixing a cooling supply air dry bulb CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 25 Fixed plate heat exchanger 4 26 2 System Design Options Fixed plate heat exchanger Energy recovery transfer devices are generally applied at higher airflows higher face velocities than what the manufacturer submits for ARI certification For example if a tixed plate heat exchanger is rated at 400 tom a typical sensible heating effectiveness is around 65 percent However it is likely that this device will be applied at a much higher airflow 600 700 fom which will decrease its effectiveness The user should work with the m
213. anual x Create Plants During simulation the program attempts to stay below the Maximum kW value by cycling off n equipment based on the assigned demanda limiting priority on bee System Control Strategies Demand limiting 5 45 Now assign a demand limiting priority to the chiller in the Cooling Equipment Controls window click Controls on the Cooling Equipment tab Finally assign a demand limiting priority to the electric heating coils on the Heating Equipment tab Note TRACE 700 can also model demand limiting for fans Shutdown priorities are set in the Advanced Options dialog box which is available from the Options tab of Create Systems 5 46 System Control Strategies Demand limiting ST a Plant description Cooling plant 1 Equgmerting Chiler 1 Free Cooling Po Type hen Fhad cooler type Nore F Egami type Hessa F Pump iene z Max chid watese 0 F z Load theddng economias No MlM Eveccivepecsing Mo ooo Energy source Reject heat to plant ooo CC 8 Erigan __ Coona Eauiomem Hews Eaatnert xj Ahunasiive 1 if Cooling plant Cookers 5 Equipment tog ECS Equpnert category waere Heas iaminn equprnert i Rave Utility Mice Accessory B Create Plants Abeomstive 1 Hears pit Heating piane 1 Equipmert tag Elecine enatance hes X Equpmert cotegoy Electr coustance Equapeert Ippe Electne Renstance Mey be Capacty Mo
214. anufacturer s representative to determine the effectiveness of the device at the desired airflow and at 75 percent of the desired airflow and then input these values for the 100 percent and 75 percent airflow points for accurate modeling Refer to Table 4 2 for recommendations on energy recovery applications in different scenarios Table 4 2 Applications for Air to Air Energy recovery Ventilation System Energy Recovery Technology Supply air Supply air Outdoorair Source Temperature Tempering Preconditioning Dedicated Cold Not applicable Sensible or total outdoor air Neutral Sensible Sensible or total parallel or series Mixed air Modulated Sensible Sensible or total outdoor air plus constant volume parallel or series recirculated return W J C V _ es air old Not applicable Sensible or total variable volume TRACE 700 User s Manual e CDS PRMOO1 EN Heat pipe A heat pipe resembles a finned tube coil Each of its large tubes is an independent sealed container that is filled with a heat transfer fluid typically a chemical refrigerant A partition divides the air side of the heat pipe into separate evaporator and condenser sections The capillary wick structure within the pipe walls induces refrigerant flow between the evaporator and condenser without the help of a compressor or pump Two air streams flow across each heat pipe Warm air flows across the evaporator and cool air flows across the condenser The ref
215. ar whenever an energy recovery transfer device is added and Allow energy recovery transfer during design calculations is turned off Food pise MX ina aie SA lempeng Found plate HX omens SA lanpernngj Heat ppe QA precornthorng Heat ppe ipx abel SA tempen Heat ppe renes SA tempang Lig Genie afiar man cig aa 1 Ug desk aher vert cy Liq desic before mar clo TRACE 700 Lig dese before vert cig Nore defn a Senedale wheel NA peecorettorenny Palle aeng camery a ditigh i currentty harrad of vos Hee Charpa Laird Paraeveeters aareen Would oss hoe bu hunny A es Sensible wheel tanas SA tempenng emo Humi Sobd dent on ret os deck Sold denic on vert deck Totas ereigy veel DA precondition W Create Systems Options Akamara System description wSHP with DOAS Wwiaber Source Heat Pump Evapematee Cocky E idrain em Type Bra Tima fia l LST Desce Os Select Ventilation downstream Dect collechacuke ee 10 i if the device is located in the cr oa 5 ae ee outdoor air stream and Indict cod schedule ble 10 downstream of the optional ventilation cooling coil E Select Return outdoor air Sage T Aiton Energy Placeveny Trancler Tyne Eere wheel joala SA piiga Suprude deck Vanian deam Erida deck Ren sy downstream if the device is cadie jvais 1005 located after the mixed air _ftieciveress Osters stream downstream of the main
216. art load conditions In applications with variable airflow the control system monitors the operation of each VAV terminal to identify the zone with the highest load It then unloads the supply fan just enough to keep the VAV damper in the critical zone fully open Figure 5 4 Fan pressure optimization damper positions of VAV terminals static pressure sensor speedor inlet vane position RO of supply fan k g eS A ERE m conse K communicating S building automation system Unloading the fan in this fashion decreases the static pressure in the duct reducing the energy consumption and noise level of the fan Application consideration m Effective implementation of fan pressure optimization requires a control system capable of monitoring the damper positions in all the VAV terminal units Relating reading m Ventilation and Fan Pressure Optimization for VAV Systems Engineering Bulletin Trane literature number SYS EB 2 E VAV System Optimization Engineers Newsletter volume 20 number 2 5 12 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Fan pressure optimization for VAV systems OH To model fan pressure optimization define the air distribution system 1 Choose the desired system type from the Variable Volume category For this example use Parallel Fan Powered VAV 2 For the primary central supply fan pick one of the predefined fan types with critical zone re
217. aseroom 125 reva Gysooms Project Navigator view BP Create Systeme Selection E co Abemative 1 rd Syanem descrigtion VAN Classname aiaia Volume Fleheat TAU Min Flow Deal pias HY Dedicated Vere gt Acheanced Oghors Fen Overices F Terpecatuse Hurrectty a Sl West Haway Jk E a Habay a E Notth South Haway EB Roos 120 Storage oy Gym Storage Room Dhoypree Bees VAM Charger del pees VAV edh Leesa Haai Project Tree view Sippass VAV sath Fiafia Dieubi uzi VA Fiala F an Formed VEV Hig Cod on Meare om Utia Farska FanePoeaed YA 2 14 Program Overview TRACE 700 User s Manual e CDS PRM001 EN Performing basic tasks alla If you assign individual rooms to a single zone SZ system or to a variable temperature constant volume VTCV system TRACE 700 treats each room as if it has a separate cooling coil For proper modeling create a zone for each SZ system then assign the appropriate rooms to each zone Refer to Zoning of rooms on page 6 47 for details on zoning CDS PRMOO01 EN TRACE 700 User s Manual Assign rooms to systems In order for the program to properly calculate the airflows coil loads and fan sizes for each airdistribution system it must know what rooms and zones each airdistribution system serves Figure 2 11 Assign rooms to systems Project Navigator view E Assign Zones and Rooms system then click New Zone Drag
218. asks i l5 Figure 2 8 Create templates Room Denplites Pro t Akemaeve l Default Ahen stve Derai Tanplated intemal losd Dest i Brew bes o Themen Dest sts lt CSs s sY Coumeion Desa i stst ts sSS a iaj ja 4 tema Load Thermostat Program Overview Performing basic tasks 2 12 Constnuction Note Additional weather locations can be imported if necessary Refer to Adding weather locations and activating the 8760 calculation methodology on page 6 167 Additional international weather locations can be downloaded from htto www tranecds com Create templates Templates establish the default values for four types of room attributes Each template is defined on a separate tab Internal load s such as people lighting miscellaneous equipment personal computers for example and other sources of heat within the room Airflow s including ventilation infiltration supply main auxiliary and VAV minimum and room exhaust Thermostat settings for the dry bulb temperatures and driftpoints during heating and cooling as well as for relative humidity Construction of the room height the types of windows and skylights and the materials that compose the heat transfer surfaces exterior walls partitions roof floor Lanai a niet rer 1 Aher apas Ihermnast t Tenlates Project i Dersy j iaeo Schedule Posing re tiigri Delta i
219. at 100S wiif 7 Coding effectneer stat at TEN biia Heating slectivencss af TOE oaii Irteeretan O Heating eliesirrer ot 72 arkar Indvect cod achedle Ev L apara Grage TAHMA Energ ety ara Hilaira ol TOUA miira Tipa ry Conky iecivernss al aie X Supra deck Verdotor Heating ellectiverecs of 100 ations 0 x Gxhede deck iyim ex Heating ebectvenedt M TSS afii lo x Additional Items When adding an energy wheel to an airside system It Is recommended that the minimum and maximum cooling supply air dry bulbs be set equal to each other to fix the value for the cooling supply air dry bulb This is suggested because TRACE 700 cannot psychrometrically solve for the cooling supply air dry bulb when an energy recovery device is attached to the Return Outdoor deck For the ramifications of fixing a cooling supply air dry bulb please refer to Frequently asked questions on page 6 20 and Oversizing and undersizing on page 6 51 Energy recovery transfer devices are generally applied at higher airflows higher face velocities than what the manufacturer submits for ARI certification For example if a wheel is rated at 400 fpm a typical sensible heating effectiveness is around 74 percent However it is likely that this wheel will be applied at a much higher airflow 600 700 fom which will decrease its effectiveness The user should work with the manufacturer s representative to determine the effectiveness of the device at t
220. at the System level Note For additional details on Systems refer to the System Type Characteristics in online Help CDS PRMOO0O1 EN TRACE 700 User s Manual Return Outdoor Deck conditioned outdoor air is mixed with the return air in the main unit s Plenum conditioned outdoor air is delivered to the plenum above the spaces Room Direct conditioned outdoor airis Z555 s Tes roi zi peat 000 Hin Fie Dolgut delivered directly to the spaces This can esne Linds also be used to model the delivery of Wha fF conditioned outdoor air to dual duct VAV boxes where it mixes with conditioned recirculated return air DUREE ST Ee Heating cod evvodabde VOECI AA Emin VICE 5 E tin Q ET W Create Systems Dedicated Ventilation Abemetrve System description VAH and DOAU Variable Volume Mehest 30 Min Flow Detak Contigurston Dehuendity ipmonty o Cool Heat Control methed Opteron Supply Ae Dew Port Cooling Heino Design Setpowts Conling Hesting Setpoint Lasts Cooling supply air dey bulb fes F Supply ai dy bulb high im Heairg sap ar dyb 0 F Supply a chy bub howe im F Cooling supply at dew pont F Cooling SA dew poirt hih ime E5 iti i S Cooling SA dew poet kow imi 5 Dedicated Vertigton Schede Dede ated Ventilation Locators Cooking cod Avelable 100 Opona favours SCY System gt The dedicated ventilation unit will
221. at the same level as the main cooling coil The System Component Selection report should be used to size the dedicated ventilation unit Same level as main heating coil The dedicated ventilation unit will be placed at the same level as the main heating coil The System Component Selection report should be used to size the dedicated ventilation unit System Design Options 4 49 Dedicated outdoorair systems E Create Systems Fan Overnides 8 On the Fans tab input the fan type and the total static pressure for the primary fan the fans in the fan coil units and the optional ventilation fan the fan in the dedicated sy rien Sm Alamaa 1 Sythe depcniption Fan Codes ard DOAJ Fan Cod Fan peeling schedule Eyck wath occupancy r i 3 ak kisim ventilation unit Seconda o Jew Teh kfm mbam kwim Ay MOO litt Next define the son ates pn Hoo k e C kahit CE cooling and heating plants represented by the fan coil system and the rooftop air a conditioner Configuration 9 Add two new cooling o A s ba Coir amenas tt man ae Mas Cooling plant 2 idedicated QA unt plants and two new N aa a ue qo tir Piara weard Heating plant 1 boder r 7 mT Mas Heating plant 2 dedicated OA un Now Cig Flara heating plants to the 6 Aa 9 W ates Doder Clectne Gartred tource he resiitance h s ent i F O S und Gilg Paes thn For cooling use water cooled
222. at would be typical for the room type being entered in Create Rooms and allow the user to override these Inputs with any atypical values for that specific room CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 125 Using templates 1 The first step in using templates is to create the templates Click Create Templates TRACE 700 will open to the Room template Note It is much easier to create templates before the rooms have been input Applying templates after the rooms have been input is time consuming and often difficult to do Refer to Additional Items in this section for instructions on reverting inputs to templated values 2 No templates have been input into this file Therefore the Internal Load tab should be selected 3 From the Internal Load tab the general characteristics of the office areas internal loads will be input Click New and enter Office Areas into the Description field Enter the appropriate Type Density Loads and Schedule for the people Repeat this for Lighting and Miscellaneous loads 6 126 Using templates Advanced Usage and General Modeling Tips In the following scenario a set of templates for the office areas of a building will be created and applied in Create Rooms x TRACE 700 for exclusive use CDS pects TRACT File Edi Adira View Optra Lires Tengides Aenaives Seip Window Heb i gt A aso Fea wt A Wl BG OM BO Room Templates Pro
223. ate Systems is not Return Outdoor deck then Return outdoor air upstream and Return outdoor air downstream will function identically TRACE 700 User s Manual e CDS PRM001 EN Desiccant dehumidification 5 Select the exhaust side deck for the device This will determine which airflow will be used as the regeneration air stream The airstreams typically used are building exhaust air outdoor air or a mixture of the two Note In this case the airflow that is being exhausted from the building at the system level will be used as the regeneration airstream for the desiccant device Because of this System Exhaust will be used CDS PRM001 EN TRACE 700 User s Manual W Teate Systems Options pes bes Bt System description System 00 Type tone Deecteiciency E oook Drect cod schede E35 6pm y ndee f 5 feamwspm x Indeect col schedule snom z Stage 1 ArtoAk Energy Recover Transier Stage 2 Aino Ensi Recower Tranater Sobd dene on vent deck Type Hore det ud Supada deck Extrtide deck F Select Outdoor amp room exhaust mix if the regenerator will first try to use room exhaust as the sole source of regeneration airflow If the room exhaust airflow is insufficient the rest of the regeneration airflow will be made up of outdoor air Select Outdoor amp system exhaust mix if the regenerator will first try to use system exhaust as the sole source of regeneration airflow If the sy
224. ately Additionally main and reheat coils are this method increases the the same It is only design sizing of the equipment necessary to oversize the Users will see this reflected in main coil the design reports e g System Checksums CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 95 Modeling for LEED Method 2 Oversize the plants Note Unlike Method 1 this method does not affect the design sizing but instead adds capacity 1 Check the Link airside coil capacities to equipment capacities box 2 On the Create Plants Cooling Equipment tab select Plant Capacity and enter 115 for oversizing 3 On the Create Plants Heating Equipment tab select Plant Capacity and enter 125 for oversizing x esaret Factoes Sendstenn hours rua yor ji Sirim Caleria code 8750 Standard Ecay 33 Cancel First month Jamuery Gor Last morth December ol x R Link aitide cod Capacies to 7s cqupmert capste Hot water 7 F Apply 08 PRM rules to fan seng Chilled water 10 Pet ASHASE Starebed 901 Dqugerant Bag ressis uriy O01 Cquprant categery Er ceed ely dhana I Henro gist Eare Faan Fuel Beda Epes Ean Y ott Note If multiple pieces of equipment are Chaparesnd Poget SL brs Gii Poel HA Walii C20 MEA mm cluded in one plant the total of the tmnt 3 am xPuretacacty equipment capacities should not exceed the
225. ather than TRACE 700 Help repeat many of the same steps for each example this section contains detailed summarizes each analysis task represented on the Project information about each Navigator palette For step by step instructions and other related program entry information refer to the tutorial in the electronic TRACE 700 Getting Started Manual and to online Help a Provide weather information Local weather conditions latitude and longitude and elevation affect the loads in a building To provide this information pick the city that best represents the weather profile that the building will experience The TRACE 700 database includes weather profiles for more than 500 cities around the world Each profile details the design wet and dry bulb temperatures barometric pressures wind velocities ground reflectance saturation curves and cloud cover This information helps the program to determine the conduction solar infiltration and outdoorair loads in the building Figure 2 7 Provide weather information 4 karm lies Limes o i zA a BAHRAT HEDRAS T eT ah ik 1 i Drit h j j f F sisi wia a 77 D eieae ereke angi bin rire rman T Bei Mere Click Overrides to view or modify the current weatherrelated values Click a region on the map to select the representative city To change maps use the Options menu CDS PRMOO1 EN TRACE 700 User s Manual Program Overview 2 11 Performing basic t
226. ation in TRACE 90 1 2007 Strategy 700 reference Energy recovery page 4 15 G3 1 2 10 Demand control ventilation page 4 91 6 4 3 9 Airside economizer page 5 2 G3 1 2 6 Optimum start page 5 6 6 4 3 3 3 Supply air temperature reset page 5 50 G3 1 3 12 VAV minimum airflow requirement Create Templates G3 1 3 13 or Create Rooms Airflows tab Design airflow rates Create Systems G3 1 2 8 Temp Humidity tab Fan cycling schedule Create Systems 6 4 3 3 1 Fans tab Note Some ASHRAE 90 1 2007 directed control strategies use airflow as a criteria in determining their use If this is the case calculate the Design portion of the baseline alternative to determine system level airflows e g System Checksums report Changes mentioned previously e g envelope should be made prior to calculation to ensure an accurate value Is determined System fan sizing System fan energy for the baseline building is determined using a formula found in Appendix G TRACE can automatically perform this calculation for both ASHRAE Standard 90 1 2004 and 2007 This feature will determine the fan s location and accomplish the calculation at the appropriate level 6 92 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Modeling for LEED To calculate system fan energy follow the procedure below 1 Check Apply ECB PRM rules to fan sizing 2 Select the appropriate standard to be used for the calculat
227. ave to be completed to determine the portion of wall conduction into the floor plenum This will be the fraction of the wall exposed to the floor plenum TRACE 700 also accounts for heat transfer between floor plenum and the corresponding adjacent space 1 Enter the percent of the eats eee Airey 1 fondu SM Second floor wall area that is exposed to the underfloor plenum Note This must be done for all spaces that have Room decipion ffxi SCS First floor underfloor plenums Temelates Room helt x i Sou Consuet F acs back Faca bitk 2 hrie Hew wal irdena Oea 0 h Uea A MaF copy Artem js h Ta T eleta Taist Sf Direction 150 deg g E Pet wal westounderioct perum o7 x f Glatt E walsmea 25 Type Doute Cesena me Ft Wsie 05 Bhar Height lf Sh Coet 055 Quanity eraj x Shedding Ierd Hone Fater CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 85 Underfloor air distribution F Create Boome Partitions and Moors 2 Room 101 is exposed to aa Firet floor the ground On the Seela Floors tab of Create Roc fostna Rooms create a New oa Floor to account for the heat transfer Utata E Biwi F Loar pasi jir Bilut F PF Create Rooms Partitiens ane Fleore 3 Room 201 is directly Foom deecipton oe Tarral Paian above Room 101 To nn Ea model the heat transfer irteinal Doia z Lergh hiik D ely Heyes i between the rooms _ create an
228. be placed at the system level It will pretreat the outdoor air for all of the rooms and zones assigned to the airside system This is the most common choice for dedicated ventilation systems The System Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Zone Each zone or room assigned directly to the system will get a separate dedicated ventilation system The Zone Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Room Each room will get a separate dedicated ventilation system The Room Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Same level as main cooling coil The dedicated ventilation unit will be placed at the same level as the main cooling coil The System Component Selection report should be used to size the dedicated ventilation unit Same level as main heating coil The dedicated ventilation unit will be placed at the same level as the main heating coil The System Component Selection report should be used to size the dedicated ventilation unit Dedicated outdoorair systems System Design Options 4 59 8 On the Temp Humidity tab specify a Maximum room relative humidity of 60 9 On the Fans tab input the fan type and the total static pressure for the primary fan the fans in the VAV air handler and the optional ventilation fan the fan in the dedicated v
229. ble Sensible or total parallel or series Mixed air Modulated Sensible Sensible or total outdoor air plus constant volume parallel or series recirculated retun Nnnn n a _ _ air old Not applicable Sensible or total variable volume TRACE 700 User s Manual e CDS PRM001 EN Total energy enthalpy wheel Fixed plate heat exchanger A fixed plate heat exchanger consists of alternate layers of thermally conductive plates that are sealed to form separate passages for two air streams The plates are constructed from aluminum or other materials with a similarly high thermal conductivity Fixed plate heat exchangers exist in various configurations materials and capacities of the available flow patterns cross flow is the most common The plates in most of these devices transfer only sensible heat between the two air streams Figure 4 8 and Figure 4 9 on page 4 22 show the typical arrangements for sensible heat recovery in mixed air and dedicated ventilation systems In Figure 4 8 which shows mixed air systems sensible heat recovery can be used to reheat the dehumiditied supply air Insets A and C or to precondition the outdoor air Insets B and C Figure 4 8 Mixed air arrangements EA SA EA SA OA RA OA RA Inset B parallel recovery stream to stream Inset A parallel recovery stream to stream SA OA EA RA Inset C series transfer upstream to downstream CDS PRMOO1 EN T
230. ble Temperature Coritani oume lai sier Soe Hasi Pum Create Systems Dedicated Ventilation Abemetrve System description Fron Cols ond DOAJ 7 Coat best Cooling Heaing Design Setponts a T 2 Configuration Dedicated Vently on Schedules Cooking cod Avate 100 Hesaro cod aveskatle 100 peel avaisi 100 7 2 Seeon Opere Dedicated OA IeroHumsy Fan Col Control method F coms Setpearts Supply oi dy bulb high let F Supply an chy bub kyr imd F Cooling SA dew point high im F Cooley SA daw point how imi Dedicated Ventilation Locotions Rer Dudo Deck System hae Deck Level Cob Fern None no dedicated ventilation unit Cool heat a dedicated ventilation unit is used to cool the outdoor air to the userinput cooling dry bulb during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season Dehumidify priority or Cool Heat a dedicated ventilation unit is used to dehumidify the outdoor air to the userinput cooling dew point not reheated during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season ib Schematic Dehumidify and Reheat Heat a dedicated ventilation unit is used to dehumidify the outdoor air to the userinput cooling dew point then reheat it to the userinput cooling dry bulb during the cooling season or heat the outdoor air to the
231. c CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 65 Airto air heat oump system 2 llay Use air cooled unitary and electric resistance to begin defining the cooling and heating plants Rename the cooling plant to Heat pump and the heating plant to Electric resistance 3 With the cooling plant displayed on the Cooling Equipment tab pick air to air heat pump as the equipment type 4 Open the Cooling Equipment Controls dialog box 5 Use the energy source entry to identify which heating plant if more than one will serve as a backup if the heat pump cannot satisfy the load 6 Assign excess heat from the condenser loop to loads served by the selected heating plant Akense S easa PE gt Aincoged Aicooked Wamo Wabes RE Air cooled unitary 007 undp gi Aircooled condenser Hesg plants iran E la Electric Resttance 64 ii Pevitarce y Garad fesiitence est dat a P cp Cirene Prange Thera liam To memp eggen dag Gre dened equpstent cega in the moniguestion ieee B create Plants The library definition for this equipment type allows it to provide heating as well as Click to save your changes Mae thie ahii rete bo F Load shedding economia Ne Evapa jnecneling ne E Eineigy toune Eene Raae a 5 Fiap concerns heat rewire piana oo Peer 6 3 66 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMOO
232. c building changes that are not accounted for during design calculations m Verify correct thermal zoning and thermostat placement Proper thermal zoning of spaces as well as properly modeling thermostat locations is vital to proper building simulation Ensure Spaces are properly zoned per design documents and are modeled correctly in the Assign Rooms to Systems section m Verity accuracy of drift point entries or thermostat schedules When a space is unoccupied less than 5 percent occupancy and there is no thermostat schedule applied drift temperatures are used as the thermostat setpoints If there is a wide variance between the occupied setpoint and the drift point the HVAC equipment may not be able to handle the pull up or pull down load in the one hour time increment as the building becomes occupied Verify the temperatures entered are an accurate representation of the actual building thermostat controls The same suggestion applies when utilizing thermostat schedules However realize thermostat schedules are not affected by occupancy like drift points Instead they follow the userdetined schedule m Limit restrictions to fan operation TRACE has fan control options allowing the program to intelligently cycle the fan to meet changing load conditions Avoid scheduling fans manually because the simulation may not match up with the expected fan operation schedule Leaving the fan schedules set to Available 100 and applying a fa
233. calculate the file using the new load profile Note Use the Alternative Setup menu to create additional alternatives CDS PRMOO01 EN TRACE 700 User s Manual Step 2 Tih eekeckie patois hares beir gogan hiy bhay belyn lea CCD SS IRACE SOD Propels ance bolle Prahat civ IMPORTANT 1 Altes exiting Alen SAVE TO THE ZAME DIRECTORY 2 Do not change the name of the empcrted fle Ai fhe pool edit the colani or roy label Dikira on Meet below wall launch the spreadsheet piai bbocisted wath cor files 15 em E Micraenlt excel Ele Edt Yew Insert Fome Took Dao Window tiep Adobe POF Ogee 647 I GEEL BE fo 1 El 4 i snog FF window e eloi At 4 A 4 2 Cooling C Heating Coils 3 fiona Day Type Hias borri hale 4 Jan Dsn 1 q Ja Den e 6 Hn Dsn 3 Li Lt 7 Jan Den 4 a a Jan Chiri E a an Dsn Ls a a 10 Ja Den i a e Bi 11_ an Usn a 4 457 07 iz Jan Den E 0 hd 13 Jan Chiri 10 7 12 Hn Dsn 11 37 52 15 Ja Den 12 a 12 ea 16 Hn Usn 13 3 14 3 24 T7 Jan Den 14 aa a 14 Ja Chiri 148 7 Ah oO 19 Jan Dsn 16 AE All Advanced Usage and General Modeling Tips Inputting an existing load profile 6 121 Creating spreadsheets and tables from calculation results TRACE 700 Visualizer The TRACE 700 Visualizer allows the user to create custom charts and tables view trends and get additional details about the loads airflows and energy consum
234. can be used to optimize the trade off between reheat and outside air intake Spaces that have lesser loads and airflows may have outside air requirements that force them to become a critical factor in the Standard 62 1 ventilation calculations By examining the Z fractions in the ASHRAE Std 62 1 report users can set the maximum outside air fraction for the system such that the program automatically adjusts the reheat minimum for those spaces to match the maximum outside air fraction Z In doing so zones that have their reheat minimum adjusted based on this constraint will see larger minimum airflows and an increase In reheat energy necessary to maintain space conditions However the resultant system outside air intake can be reduced and therefore may result in overall energy savings An iterative process may be required to determine the optimal ratio 2 There is an additional option that is available when ASHRAE Std 62 1 2004 2007 w Vent Reset is selected The CO2 based Demand Controlled Ventilation DCV is enabled and can be set to None Proportional Control or Single Setpoint CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 95 ASHRAE Standard 62 1 4 96 System Design Options ASHRAE Standard 62 1 Proportional Control is detailed in Appendix A of Standard 62 1 2004 a When Proportional Control is selected the outdoor air controller will adjust the outdoor air intake flow proportionally between the minimum ve
235. cenario TOPSS will be used to select a DX cooling coil in a rooftop unit Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Selecting a DX unit using TRACE 700 output aaral F kda i a Re pra Epi NO SWoR EIERN OTe ene BEaa ERTE T oad Fina aa t Ezi X amp be 3 i P a E SOG DON SELECT Le ie HE i a a atten E Pre mia iya Pij ER RE ig 1 After calculating the ae ae Sa Fee ee TRACE 700 file there are AT ro A several output reports that can be used to get the data required to select the cooling coil For the Variable Volume Reheat system used in this example the System Checksums report and the System Component Selection Summary report can be used we e ma me me aa n ve oe s e Ss we n ne ar 2 From these reports the Total Capacity Peak Airflow Entering Dry The following numbers will be used during the Bulb Entering Wet Bulb selection process and so forth can be Total Capacity 37 4 Tons 448 9 MBh taken Sensible Capacity 369 4 MBh Supply Airflow at Space Sensible Peak Load 19 575 cfm Supply Airflow at Cooling Coil Peak Load 19 329 cfm Entering Cooling Coil Conditions DB WB 76 5 F 63 8 F Entering Main Heating Coil DB 53 7 F Altitude from Title Page report 812 feet CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 69 Selecting
236. chiller Condenser tower shotage a and air cooled unitary For heating use boiler and gas fired heat exchanger To asagn equoment dag it delers mrn Sener a ore Configuration pane k 10Drag the appropriate icons from the Equipment Category section to define each plant EEA A 11 To finish defining this equipment enter the information from Table 4 6 on page 4 51 Co on the appropriate Bat Cocina let rer coed ce equipment tab Se eee Aas Cong part 24tedcated OA ura oo ian as lt a E Optional Vertiation Heating Cod New Heat Ploni z2 Finally assign the coil loads of the airdistribution system to the proper cooling and heating plants Before 12Drag each coil in the S T Cooling Syitem Fan Colt and DOAL g lt pr a _NewSystem Coils pane to the 5 am Cong prt 2 nda Aw EE O Cooling Syitem Fan Cods and DOAU appropriate plant in the oy rao Sys f PI z Mra p arenira peseta m Heating System Fan Code and DOAJ al di E Cpnus Veetitealieatgts ce pane The illustration labeled After shows the completed assignments 4 50 System Design Options TRACE 700 User s Manual e CDS PRM001 EN Dedicated outdoorair systems Table 4 6 Equipment types Cooling Equipment tab Heating Equipment tab Watercooled chiller 2 stage centrifugal gas fired hot water boiler Aircooled unitary split system RAUC rooftop gas heat 20 ton scroll Scenario 2 A building is served by a wate
237. constant volume systems To specify a supply airflow for these system types the user will need to input the airflows at the room level on the Airflows tab of Create Rooms or in the Airflows template s and TRACE 700 will sum the room level values to get the supply airflow The program will also determine the resulting room relative humidity based on the specified airflow and will report it on the Psychrometric State Points report If the desired relative humidity is not achieved it may be necessary to Input the supply air temperature CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 21 Frequently asked questions If both the supply air temperature and the supply airflow are specified the coil capacity is locked in based on over specification of the sensible heat equation TRACE 700 can only compare the calculated load to the specified coil capacity and report the difference between the two numbers as the over sizing or undersizing of the coil For more information related to over undersizing please refer to Oversizing and undersizing on page 6 51 Q How are split systems modeled A TRACE 700 treats a split system defined as compressor and condenser outside and DX evaporator coil inside exactly like any other air cooled DX system To model this the user can choose either a rooftop or an air cooled condensing unit from the Equipment library If the split system consists of a chiller with a remo
238. cribe the cooling and heating plants that will satisfy the coil loads 1 CDS PRM001 EN TRACE 700 User s Manual To represent the rooftop air conditioner drag the air cooled unitary icon to the cooling plant On the Cooling Equipment tab select a specific equipment type Drag the Electric resistance icon to the heating plant to represent the electric heat coils in the VAV terminals Create a new heating plant to represent the boiler that serves the humidification coil On the Heating Equipment tab select the Gas Fired Steam Boiler Assign each coil load to the appropriate plant 106 5 lias Space Heating E Electric Resistance 00 Boder Electr Garfred fesutance heat exc Cookery komer E o Not shown Finish describing each Purga plant by specifying the equipment type and full load consumption on the Cooling Equipment and Heating To stugh equpmert diag the dained eq E Man Cooking Cot To assign the system and associated coll loads drag the relevant icons to the appropriate plant Equipment tabs ia Hurredification g Heating System VAV system 1 E Huasin Heating Cot llas Space heating Ig Heating System VAV eyetern 1 S E Mann Heating Col E fetes Col E Prehent Cod System Control Strategies 5 11 Humidification Fan pressure optimization for VAV systems Fan pressure optimization is a control strategy that reduces the energy use of the supply fan at p
239. cts the overall part load efficiencies of the HVAC equipment whether air or water cooled For your convenience condensing iS used the TRACE 700 Equipment library The loads are translated into energy consumption by source The already contains the scope of these calculations includes district hot and or chilled required information water and the total amount of makeup water required by a about the part load performance for specific HVAC equipment cooling tower even the energy consumed by the crankcase heaters of a reciprocating compressor Required entries are limited to the types of ai moving heating and cooling equipment used For hydronic plants you will also be asked to enter the total head or maximum energy consumption and motor efficiency for each pump Armed with this information the program extracts the appropriate performance information from the Equipment library and converts the system loads to energy consumption Phase 4 Economic analysis Put simply the final phase of calculations determines how much it costs to own and operate a building including monthly and yearly utility costs over the life of the HVAC system To aid system comparisons TRACE 700 also computes various financial measurements such as cash flow effect profit and loss effects payback period present worth of savings and the incremental return on the additional investment To complete these calculations the program uses the energy consumpti
240. culate individual fan and coil sizes for each of the 200 fan coil units CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 49 Zoning of rooms After calculations have been completed the user would want to look at the System Component Selection report or Rooms Checksums for all coil and fan sizing information 6 50 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Zoning of rooms Oversizing and undersizing Over undersizing which appears on the Checksums and Airflow Loads reports typically occurs with constant volume system types especially Single Zone SZ Fan Coil FC Variable Temperature Constant Volume VTCV and Multizone MZ systems The following airside system and rooms will be used to illustrate over undersizing and how it is calculated in TRACE 700 Figure 6 6 Airside system and rooms Exhaust Return Air Air ACU Ventilation Supply Air 1 Room 1 The sensible heat equation will be used to calculate the sensible loads airflows and sensible over undersizing Q DSHPx SAx T i where m Q is the sensible load in the space calculated based on the input walls windows internal loads and so forth A positive value indicates heat gains and a negative value indicates heat losses Qs can be found on the Checksums report CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 51 Oversizing and undersi
241. curve to calculate the energy consumption of the VWSHP compressor In the case of GSHPs the unloading curve is the same regardless of mode and the ambient modification curve for heat recovery mode is now based upon the minimum entering condenser water temperature approximately 40 F rather than the design entering condenser water temperature approximately 85 F used for cooling The full load energy rate for heating mode should be determined at the temperature specified for the Minimum Condenser Temp which is actually loop temp for WSHP and GSHP The Heat Sink Delta T TLoopAvg MinCondTemp CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 35 Frequently asked questions 6 36 Q What should be selected for the Heating Plant for a ground source heat oump system What should be selected for the Heat Rejection type The heating equipment is used to define a backup heating plant The backup heating equipment is used to keep the water loop from falling below the minimum condenserwater temperature Typically a boiler should be selected as the backup heating source The heat rejection equipment selected as the Heat Rejection type is used as a backup to keep the water loop trom exceeding the design condenser entering water temperature Typically a cooling tower should be selected Note If the entered GSHP system has a large enough water loop entered as the thermal storage capacity the minimum co
242. cy as possible Five types of schedules are used in TRACE 700 E Utilization Schedule This type of schedule is used primarily to vary control the internal loads airflows fans coils control strategies and base utilities Utilizations schedules are used in almost every section of TRACE 700 E hermostat Schedule This type of schedule allows you to vary the thermostat setpoints by hour and is selected on the Rooms tab of Create Rooms and the Thermostat tab of Create Templates E ime of Day Schedule This type of schedule is used to determine what are hours on peak off peak etc for the associated utility rate and is used only in the Economics section of TRACE m Fquipment Operation Schedule This type of schedule allows you to designate the sequence in which cooling or heating equipment operates when there are multiple pieces of equipment working together Equipment operation schedules are used only on the Cooling Equipment and Heating Equipment tabs of Create Plants E hermal Storage Schedule This type of schedule dictates how the chillers and thermal storage tanks operate during the simulation Thermal storage schedules are used In only in Create Plants CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 137 Creating schedules _ Click Schedules on the Libraries menu 2 The Library Template Editors program should open to the Utilization schedules 3 To create a custom schedu
243. d Changes to the rooms airside systems and templates are not allowed with TRACE 700 Chiller Plant Analyzer o TRACES T00 ily elie birai Hele 1 Open TRACE 700 click ie o carl 7 Caa Dairy oa TRACES Mi Lord ulep New on the File menu Archon Profechsn TEAGEN Ton Chile Mint Anatyoe cil Bumn hing Remus and click TRACE 700 impart es Ijz Chiller Plant Analyzer con end walaa 2 Enter a name for the arama A N project and click Open none Fii al ppa TRACE Chukar Plat Arushaner Files Cancel Hep 3 Select the desired plant configuration for the TEHETE cooling equipment and Paolo Chen Funka d Ohler VEL Tar click Next Plai oral Frere Fizi Condy Reto at Mazar Sheer Cocke Frees Dinit Parabel chaler plant 1 jung per chalet Tertiage centilugsl chian paped m paaie yath speed caoire lover bch chide haa a constant volume chilled ater pump 125 ftreg and a conatant wolune condens pump TE vag Note If changng the chiller hpa ure must neapecity pump inbormestion 3 tack EE 6 118 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN Inputting an existing load profile 4 Select the region and then the city where the building is located and click Next 5 Select the type of building to be modeled input peak cooling and heating loads and click Finish Note If the exact building type is not available select something with similar loads and
244. d Additional item 1 All files that are to be combined should have the same weather location and the same input data under Change Load Parameters on the Actions list 6 178 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Combining files Creating a new file based on an existing file Note VERY IMPORTANT t is recommended that you back up or archive the existing tile before beginning this process 1 If a project file is open click Close on the File menu 2 Click New and then New File Based On on the File menu 3 Enter a name for the NEW file and click Open Note VERY IMPORTANT If an existing file is selected IT WILL BE ERASED 4 Select the existing project and click Open 5 Select the alternative that will be used in the new file 6 TRACE 700 will create a new Tile with the selected alternative as Alternative 1 To create a new file using an alternative from another file the New File Based On feature can be used 1 ARAL ee Te A Tetoriahetre re T japmRaggt Ticat Tit fF iaag Arie Tjenare i T ASHRAE GITRCBARTAG F EnegyTnoralwe T THACEOOOE F omisid Tili ti T Unang Tuori tre kil Tiha ii IT Coen pleted LBbatorial ee TEn Tutor gIBAa TAC TRAC EOE E KacwProfile va E Travan iF iapa Maing JB Pred eotd T ARHRAE EITRCBAK TRG T Energy Toria wa Fjona T bibisi Tili tr HE Tubaria e T Tiha i T Senptened L Enron ee TEn Tybori pIBAR TRE F
245. days of the week plus a design day and a holiday Although the calculation process lasts 5 to 7 times longer than a reduced year analysis you can use the additional day types in a full year analysis to more accurately represent the actual day to day operating schedule of the building Figure 2 16 TRACE 700 Weather library w Libeary Teenplate Pcitors 7 x File Wew Options Window Hep COTR Se Ose iss oome TRANE GB Weather Utrary General Information Res Sabres l Urana States 7 Nerth Carem 7 iroso Wiconsn 7 ASHRAE Cienatc Data Latte deg Teee fF pase Station WMO N 720455 Longitude ea deg Desig morth a Aude pe n OA fae in Ho Station Name Maedowsc Mure Awos Winter Design nex Ws OADB OAwB Gund wee Dymus 4 24 F E Clemness efit moh Cooling Mammum DB Mean Comedert WB Sumea 06 v4 fi foz 22 z 1 2 Wna 5 fi oz fis Dym er ais 75 Seana Catt Dennen Fee ee He C Coe D s Coel Coel B Cort l axana HHS lamas Octsered Mace DB Mean Conesdert 08 L 0s 1 2 Commearte DyBue 733 753 742 Wet Bub 7390 71 40 cari DewPor Tis a6 662 Note Reduced year schedules can be used for both methods of calculation Full year schedules should only be used with full year simulations For additional details refer to Creating schedules on page 6 137 Note When you import a standardized 8760 weather file into TRACE 700 the program creates a separate set of
246. decrease its effectiveness The user should work with the manufacturer s representative to determine the effectiveness of the device at the desired airflow and at 75 percent of the desired airflow and TRACE 700 User s Manual e CDS PRMOO1 EN then input these values for the 100 percent and 75 percent airflow points for accurate modeling Refer to Table 4 3 for recommendations on energy recovery applications in different scenarios Table 4 3 Applications for Air to Air Energy recovery Ventilation System Source Dedicated outdoor air Mixed air outdoor air plus recirculated return alr CDS PRMOO1 EN TRACE 700 User s Manual Supply air Temperature Cold Neutral Modulated constant volume Cold variable volume Energy Recovery Technology Supply air Tempering Not applicable Outdoorair Preconditioning Sensible or total Sensible l parallel or series Sensible l parallel or series Not applicable Sensible or total Sensible or total Sensible or total System Design Options Heat pipe 4 33 Sensible wheel Sensible energy rotary heat exchangers sensible energy wheels are similar to total energy wheels in both price and appearance The main difference between the two types of energy wheels is a coating that is applied to the total energy wheel that allows it to transfer moisture in addition to sensible heat Sensible energy wheels are typically applied in scenarios where
247. degrade Iindoorair quality To avoid overpressurization provide a means of exhausting large amounts of air from the building during the economizer mode Position intakes to avoid bringing contaminated air into the building Sample scenario An enthalpy controlled economizer is available to provide natural cooling whenever the enthalpy of the outdoor air is less than that of the return air The outdoor return air dampers can be opened to supply 100 percent of design airflow TRACE 700 can model three types of airside economizers Enthalpy Dry Bulb and Wet Bulb wr eate Systems Options pes bes bt VAW va Baseboard Heating La Evapoestive Cooling Economizer Coni is z i Dereon I2 S E 3 maen fT Schodde avaisi n00 Indeect col schedule Stage Aatodis Energy Recover Tranier Stage 2 Aitodar Enaigy Recoweny T canater Type Nenetsia ST Type Nove detma Supsidedeck Voron uom I Supuiedeck Verniso upsa x Extriade dech Ouida k room erhat moe v Exbraide deck Outdoor i room er me Shadda favie a Schade avan SS Eeen EE EE E Selection Options Dedcoted OA Temo Humdty Porn Cols Schematic Available 100 means that the economizer is available but not necessarily on every hour of the year If On point is not blank then whenever the enthalpy of the outdoor air is below the On point the outdoor air dampers are fully open System Control Strategies Airside economizers 5 3
248. derestimated Example 5 Abematve 1 System description ATu VAW ve Baseboard Heating Fan cycling schedule No tan cycler Avolstie 100 Avvoiatile 100 Avelabhe 100 Avaable 100 Avaliable 100 Avalable 100 1 The selected fan schedule does not allow the fan to run at hours when heating loads occur If the fan is turned off the heating coils cannot consume energy Schedules for fans should be used only when the fans are turned off for certain time periods and not allowed to turn back on no matter what the temperature is in the space The schedules Off 0 percent and Heating Only Design would be two examples of 6 42 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN No or low heating energy consumption incorrect schedule selection Refer to Frequently asked questions on page 6 20 for additional details regarding how fan schedules and fan cycling operate in TRACE 700 Example 6 B create Systems Heating and Cooling Col Overrides X ot Deen Coding Capscty fovadiatde 100 __ d Design Cosing Capacity Avelatle 10T Fovedatle 1003 Avaste 100 oni 2 Avalie 100 Avenatie 100 Waning The fields marked in red require other entries for a conect simulation Contact C 0 5 Support ot 606 787 3826 tee a detailed explanation 1 The heating coil s capacity has been zeroed out This will cause the program to eliminate all energy associated
249. des ambient relief the Web site http Awww tranecds com commercial software unloading xls contains a spreadsheet that will convert the existing curve to an approximation of the Power consumed curve without ambient modification and or relief 4 For increased accuracy an Ambient modification curve should be created for the equipment Please note that different compressor types and compressor designs will have different ambient relief curves Using the correct ambient modification is therefore essential for accurate modeling The following Web site contains a spreadsheet for calculating ambient relief curves htto Awww tranecds com commercial sottware condenser 20relief 20calculator xls 5 Trane Official Product Selection Software TOPSS can be ordered by contacting C D S at www tranecds com or from the TRACE 700 application click Help gt Trane on the Web 6 The unloading curves and ambient relief curves should be based on compressoronly values Some manufacturers include supply fan and condenserfan data in the capacity and power values they publish CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 149 Creating equipment and unloading curves 6 150 Creating utility rates Advanced Usage and General Modeling Tips Creating utility rates Several different types of utility rates will be discussed in this section stepped time of day stepped with a kWh kW flag and time of use Example utili
250. dify the outdoor air to the userinput cooling dew point then reheat it to the userinput cooling dry bulb during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season 4 52 System Design Options TRACE 700 User s Manual e CDS PRM001 EN Dedicated outdoorair systems 3 Select the control method for the unit Because the dedicated ventilation cooling coil dehumiditfies the outdoor air to cooling supply air dew point and reheats it to room neutral or the dedicated ventilation heating coil heats the outdoor air to heating supply air dry bulb Fixed Setpoints will be used 4 Input the Cooling and Heating Design Setpoints In this scenario 55 F should be input for the cooling supply air dew point 70 F for the cooling supply air dry bulb and 68 F for the heating supply air dry bulb 5 Select the schedule for the coils and fan in the dedicated outdoorair unit Note If a custom schedule is created for the fan or coils it is recommended to use values of 0 percent for hours off and 100 percent for hours available to run to avoid confusion W Create Systems Dedicated Yentilation Akamara syin devcistin WEEP ed DOA e Wale Sanca Hort Paro _ Cancel Configuration Dahun and Mehes Heat Cina mihal Front Seleri 3 Cooling Haning Design Setpaintt Note For additional information Coning mock or dy bub related to the other Control
251. dling system the percentage of wall lighting and miscellaneous loads assigned to the plenum and the amount of outdoor air needed for proper ventilation at design conditions By applying these entries to standard procedures outlined in the ASHRAE Handbook Fundamentals TRACE 700 determines the quantities of outdoor air and supply air as well as the supply air temperature unless already specified by the user The program also calculates the design cooling load and the design heating load for perimeter and interior spaces Phase 2 System simulation During the second phase of calculations TRACE 700 applies all of the building variables that affect system operation by air distribution system and by hour to translate building heat gains and losses into equipment loads In effect TRACE 700 follows the air as it travels throughout each alr distribution system gaining or losing heat and or moisture along the way TRACE 700 User s Manual e CDS PRMOO01 EN Completing the airside system simulation defines the equipment loads for air moving heating cooling and where applicable humidification by system and by hour Phase 3 Plant equipment simulation The objective of the calculations in this phase is to translate the equipment loads by system and by hour into energy consumption by source To accomplish that task the program applies the hourly equipment loads for each system and the TP relevant weather data Weather affe
252. dual fuel applications The interior zones in many buildings require yearround cooling during the day even when the temperature outside Is 20 F or less Such conditions also require heating at night and in perimeter zones during the day Depending on the load profile of the building it may be cost effective to design an HVAC system that uses two sources of heating energy For example if relatively little heat is required during the day the terminal units may be equipped with small electric heat coils An inexpensive heat source such as natural gas can then be used to handle the increased heating load that exists at night and during morning warm up Note To conserve heating energy it is common practice to set back the thermostat during unoccupied periods Morning warm up describes the control strategy that restores the desired space temperature in time for occupancy Figure 5 7 HVAC system with two energy sources for heating packaged air conditioner with gas fired heat air terminals with electric heat Application considerations m Controls must be provided to switch from one heat source to the other m A dual fuel system design may be ineligible for the special rates that some utilities offer for all electric systems 5 20 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Morning warm up for dual fuel applications J Use the Library Template Editors program to create a schedule for the thermos
253. during design calculations is turned off 3 Amessage will appear that asks whether the user wants to account for energy recovery transfer during the design and energy analysis simulations or only during the energy analysis simulation Select Yes for this example Lan desi hehe werd cig Hewes chet Sarika ma LL peor E Semt FarrPowsed VAV A m Select Ventilation downstream if the device is located in the outdoor air stream and downstream of the optional ventilation cooling coil E Select Return outdoor air downstream if the device is located after the mixed air stream 4 Select the appropriate supply side deck for the device For this example Ventilation downstream will be selected as the supply side deck The coil loop will be used to Indeect col schedule T Stage 1 Altos Energy Recowerp Transter Type Cod loop varies tuple tempenng Supsidedeck Vertieton dowutreem A4 Edrie deck Reun ovdow a upiresn Schade Ava atie 100 y reheat the ventilation air encores Opora downstream of the main cooling coil downstream of the optional ventilation cooling coil Selection Options Dedicated OA Temp Mumdty Fons Cok J___ Schematic 4 12 System Design Options TRACE 700 User s Manual e CDS PRM001 EN Coil loop for exhaust air energy recovery Nore pam Type None X Type Dectes oo re Deect cod schedule 6 se bof pn E Maxcudhoor f neee D
254. e Hourly ambient wet bulb offset WF Cogeneration type v Secondary distribution pump Type Yar vol chill water pump 1 4 Full load consumption f 00 fit water Thermal storage Type GLHE designed for 20F 11C TD wellfield Capacity i 3 gal ton b Schedule Heatpump ti m Geothermal Loop TLoop Ent Bldg iGSHPA 12 tore Flow rate f 00 x of condenser flow rate Loop pump var vol geothermal loop pump H E F L rate fioo lit water Flow scheme Bidiectionalcascade O A Number of simulation years Ss Loop fluid glycol percent fo Heat exchanger approach fp F CDS PRM001 EN TRACE 700 User s Manual Cooling and Heating Plants Central geothermal chillers 3 79 15Enter the evaporator and condenser energy transfer pumps within the Base E vap enengy harales purp Utility Misc Accessory A Sa i a screen The evaporator energy transfer pump will be activated when the chiller s are in cooling mode and the condenser energy transfer pump will 100 Eneu Ome 4 be activated when the chiller s are in heating mode In simultaneous mode both pumps will be active The pumps only need to be assigned to the Adonai 1 Cooling Plant using the Hewing plant Eochu reing waer a Plant field To ensure i l z PE Equpmeri category Doder proper bidirectional cascade wey pump modeling it is critical to use the standard library oon a Eneegy rate e33 Pescere efficien
255. e process of entering and changing room information They are based on the idea that several pieces of information are common for many If not all of the rooms or types of rooms in a building Examples of this type of similar information include design thermostat setpoints wall roof floor construction types amount and type of lighting and so on Templates are similar to the concept of Master Cards in TRACE Load Design 600 The templates were designed for use In conjunction with the Create Rooms Single Sheet tab to allow the user to enter room information on one screen This allows much quicker entry of room data In addition because the user does not need to repeatedly select construction types densities and so on templates reduce the chances of input errors Finally templates also make changes to files and comparisons between alternatives much easier There are five types of templates However the Room template acts as a super template It does not contain any specific room data but it allows grouping of the other four templates listed below E Internal Load template E Airflow template E Thermostat template E Construction template Templates are generally created for each type of room in a building office areas conference rooms hallways rest rooms and so on After the templates have been set up they are applied as appropriate to the individual rooms in the Create Rooms section The templates will bring in values th
256. e 4 1 suggests desiccant dehumidification requires a process air stream and a regeneration air stream In this example the moisture in the process outdoor air stream is absorbed by the desiccant wheel which then releases the collected moisture in the regeneration exhaust air stream Figure 4 1 Airdistribution system with desiccant dehumidification regeneration air stream system exhaust SYS EXH deck gt S S return fan gt central 9 p exhaust air S D Be o w oO recirculated air runaround 9 loop space 1 F m gt E gt iad gt S 9 radiant ht se e S zj 2 ve outdoor alr 5 q space 2 VAV d supply fan i process air stream PRY radiant ht Continued operation of the desiccant requires a regeneration process Regeneration is usually accomplished by applying heat to the regeneration air stream before it reaches the desiccant Consideration of desiccant dehumidification is warranted whenever one or more of the following conditions is true of a prospective application The latent load is significantly larger than the sensible load m Ihe cost to regenerate the desiccant is low when compared to the cost associated with overcooling the space m The humidity control level in the space would require chilling the System Design Options supply air to subfreezing dew points when vaporcompression refrigeration alone is used
257. e Base Hasy demand 00 oom Hi3 1 Utility librar Schede voisin 100X pate To include domestic hot water in y r Enenytype Process hot rarer toad 14 the heating energy calculations provide temperatures when the hourly demand is a flow rate Note Entering and leaving temperatures are only 2 Rename the copy and add comments if desired 3 Replace the existing hourly demand with 200 gpm available when using units of gpm or Ips 4 Change energy type to Process hot water load 5 Provide the water temperatures entering and leaving the boiler 60 and 105 respectively and save the new utility 6 Using ilg add a boiler to the heating plant Abomatrve 1 Qupmert Category A tt a wf Aatcoed Ancodked Waterco Wataita ches uray chiller untoy M Elect Garfred 6 7 Define the domestic hot water load as a base utility using the new library member created in Steps 1 through 4 Assign it to the heating plant and click Apply Domestic het water few ine Deneio 7 Oomer hat mater forrasa af Park resting clare 002 8 Specify the equipment type and full load consumption of the hot water pump on the Heating Equipment tab HOH LLL Be CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 63 Domestic hot water assigned to a boiler Air to air heat pump system alls Oversizing the cooling capacity of the heat pump lessens the use of electric heat bu
258. e Edt Actors View Options Liearies Tempides ABertulives Setup Wirrdow Help Seo SR Or ketevwe STE H TRANE At this point TRACE 700 can calculate design loads and a yearly load profile If the remaining sections of TRACE 700 are completed the file can be used for energy and economic analysis CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 113 Quick building inputs via the New File Wizard Using TRACE 700 Chiller Plant Analyzer When using Chiller Plant Analyzer no changes can be made to any inputs in Create Templates Create Rooms Create Systems or Assign Rooms to Systems The TRACE 700 Chiller Plant Analyzer is intended to be used to quickly model chiller plants using an approximate or custom load profile In this example a chiller plant with two chillers in a decoupled arrangement will serve an office building in Dallas Texas 1 Open TRACE 700 click New on the File menu so TRACCS FOO bor exclusive use by and click Chiller Plant SN mace m chta ste anana a Analyzer ee ae p Tirer le Bred On axl Tuhod Salling Look in 9 Protects 0 d E 2 Enter a name for the m project and click Open 3 Select the type of chiller plant to be modeled If Faron 2 the exact plant is not EA a available choose Hap something similar and click Next Deccupled chile plani poman secceiany pargar agyara kerilent e d elie pent te 4 Click the appropriate c
259. e and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Modeling large rooms and zones Zoning of rooms Room and zone assignments In TRACE 700 the Assign Rooms to Systems section of the program is used to configure the rooms and zones on the airside systems Airside systems can have system zone or room level coils and fans For accurate simulations correct zoning is essential because the level of the fans and coils will affect how the rooms and zones should be configured The following three examples show proper configurations System level coils Figure 6 3 Typical VAV example OF VAM w Fh oF VAN w Rh oF VAN w Rh 1 oF VAN w Rh E East Office d East Zone L d E ast Zone L d 2 Room Zone g west Office L g East Office L g East Office F g East Office d west Zone gE VAV ws Rh 2 E west Office L g west Olfice L g West Zone L gp west Olfice East Room West Room East Room West Room Note To model the far right example for energy analysis the user would also have to specify a Thermostat location of Zone for the rooms served by the same terminal device The following systems have system level fans system level main cooling coils and system level preheat coils by default CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 47 Zoning of rooms terminal reheat all VAV systems all constant volume mixing systems and all induction systems In TRACE 700 a system level unit serves al
260. e being modeled as a single space This can cause the internal loads to negate the envelope losses leading to an underestimation or elimination of the heating loads in the energy simulation Because internal loads are typically neglected during the heating design calculations reasonable heating design results may be returned using this assumption Modeling interior and perimeter areas as separate rooms will eliminate this modeling error Refer to Modeling large rooms and zones on page 6 45 for a detailed explanation Example 2 interna Deine fai Dase 3 Taa Desa 7 Comm Dess v Ugis Twe Heat gain 1 aft Moecefarrous inact Tap Misc Load 1 Erangy fas wrn enemy Etectncty 1 The Cooling Only Design schedule is selected for any of the internal loads This schedule should typically only be used for design calculations not for energy analysis It simulates 100 percent of the internal loads in the building 24 hours a day except during the heating design portion of the calculation which may not be what is actually occurring in the building This tends to lead to the internal loads meeting the heating loads To view the schedule click Schedules on the Libraries menu and select Utilization as the schedule type Here the user should be able to view the schedule and find schedules that more closely follow the actual operation of the building 2 The internal loads are scheduled as Available 100 This schedule sho
261. e coniguzaton bee 4 g Equoment Configuration _ConingEqupmert y Misc Accessor Adematree 1 Heating plat Purchased District Steam gt Eqdomertiag POS 5 E quapmert cobegory Boder gt Eaamert Purchased Onine Steam 5 Thermal storage Capacity Type Nore Eng rate fio Percere efficient Copecty or Schedule 519 E5020 Heaters waer cec purmo so de fo it water Create Plants Equement schedule Avaliable 100 ba Wel n PucheedOwnhawae a Quipmert tag rovew 5 X o O ppa Puachared Datnot Hat Water 5 z rae ig Capacity a ie fe CS IM Eng rate fiw Percer ethen Copacty 0 fior z Hol waia pump Type E5020 Heat water cae pump l Equipment schacde avait 100 Full load naea fs fi O Ls mz Cookrg Cqupmert Heating Equipment Bape Uy Mirc Accessoy TRACE 700 User s Manual e CDS PRM001 EN Purchased district steam and purchased district hot water Plate and frame free cooling Tie One way to reduce the energy consumption of a chilled water plant is to precool the water in the chilled water loop before it Plate and frame enters the evaporator This can be accomplished by piping a heat exchangers are plate and frame heat exchanger into the chilled water and sometimes referred to as condenserwater loops Using the piping arrangement shown in waterside economizers Figure 3 9 free cooling and mechanical cooling occur simultaneously Plate and frame fr
262. e e eerisy Eicon ruek Fate Defintion Ee concurence Mri chupe Stat period End pened December Rate ype Opes Mrima demand Fuel adana fon Customer Che OO kwawo o 3 In this example the utility charges 0 040 kWh for off peak consumption and a fuel adjustment charge of 0 01 kWh Fle vew Opions Window Hep OTAS giy iiA co DS AUS In this example the utility charges 10 45 kW for all on peak demand kwnawmo fie In addition the utility charges a minimum demand of 80 percent of the previous 11 months maximum on peak demand Advanced Usage and General Modeling Tips Creating utility rates 6 157 w Library Template Editors siol Opos window Hp Ph vw OTE lt te eeisy eas cons rnek TRANE 9 Click New Definition to define the next utility in the rate structure This In this example the utility charges time off peak electric 6 05 kW for all off peak demand demand will be defined In addition the utility charges a minimum demand of 80 percent of the previous 11 months maximum on peak demand w Library Template Editors lol Opina Window Help Ph vw POTaKx lt te ese ITEE cons 4gSex ev TRANE 10Click New Definition to can define the next utility in Endpecd fOxete J the rate structure This re Raees Once time gas will be defined oe Ls Click Save and then click a 10 Mendes Close In this example the ut
263. e energy analysis simulation Select Yes for this example Select the appropriate supply side deck for the device For this example Ventilation downstream will be selected as the supply side deck The sensible energy wheel will be used to reheat the ventilation air downstream of the optional ventilation cooling coll System Design Options Sensible wheel Sample scenario To input the type of heat recovery in Figure 4 13 Inset A we will model an office building with a dedicated ventilation unit make up air unit that dehumidities the outdoor air and then reheats the air to a room neutral dry bulb temperature before the air is delivered directly to the space VWatersource heat oump VWSHP units are installed in the ceiling plenum above each room and handle the cooling and heating needs for the rooms To reduce the amount of reheat energy needed a sensible energy wheel will be used to remove heat from the exhaust air stream and reheat the dehumidified outdoor air ied wil W Create Systems Options m Ez Click Yes to activate energy recovery Abematrve System desciotin sir anos wltransfer for design and energy analysis Click Evaporative Cooling e No to ignore energy recovery transfer during the design calculation and include it only during the energy analysis simulation Indeect elficency Inderct cod schede l Staze 1 Atos Energy RecovernTranster Note This message will only appe
264. e equipment type tells TRACE 700 the type of fuel that will be consumed by the equipment the unloading curve auxiliary energy consumers full load energy rate and so on Not selecting the appropriate equipment type can lead to highly inaccurate energy consumption results Energy Only Multiple pieces of equipment are assigned to the same plant but the sequencing type Is set to single This is not a valid input and can lead to the chiller plant operating incorrectly Energy Only Multiple pieces of equipment are assigned to the same plant but the capacities of the individual pieces of equipment have not been input This is not a valid input and will lead to the first piece of equipment handling the entire load Energy Only For any type of heat pump equipment the heat recovery capacity and or heat recovery energy rate of the heat pump has been deleted on the Cooling Equipment tab of Create Plants This value tells the program how much heating and at what efficiency Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes the heat pump can provide based on the cooling capacity Removing these values disables the heating energy consumption of the heat pump unit Energy Only m The pump full load consumption has not been input Without a pump head or size the program cannot calculate pump energy Energy Only Base Utility Misc Accessory tab of Create Plants W Create Plants
265. e h s ec P cp Cookery Paargs Thema timer thosga Category section on the Ancodled Aincocled Waterco Waterco chiles ukay left side of the screen click a Boiler and drag it over to the heating plant 4 chiller unteoy 2 M Electrc Garfred resutance heat enc amp a F oo Ancodied Cocker Pumps Thermal tomer Cordano CDS PRM001 EN TRACE 700 User s Manual To stupi equpmeri dag the deized equperari calegory lo the conigzahon bes Cooling and Heating Plants Purchased district steam and purchased district hot water 3 41 3 42 3 Click the heating plant click Edit and rename the plant Click the Heating Equipment tab In the Equipment Type list select the appropriate equipment type to be modeled Purchased district steam or Purchased district hot water It is also recommended to change the Equipment Tag to a more appropriate name Input the appropriate pump type and the full load consumption for the pump Purchased district hot water only Cooling and Heating Plants Arcokd Waterco Waterco ik ur oy chiller utay _ Now Cig Plot uo H te PE cate Plants 5 xj Ahenstive 1 ou Pt Equpmert Category Arcod Waterco Waterco urtay chiller urday so HA Water Electr Garfred taue he resutance heat enc a Poo Ancoced Cookeg Puree Thermal Condenser timer thotage LEE EE RE k To stug equement dag the deteed equpment calego lo th
266. e room exhaust airflow is used exclusively as the exhaust side Room exhaust airflows are input on the Airflows tab of Create Rooms If no room exhaust is input then all exhaust air will be at system level m Select Return air if airflow returning back through the plenum or return duct pre system exhaust and post room exhaust is used as the exhaust side TRACE 700 User s Manual e CDS PRMOO1 EN 5 Choose the schedule that describes when the heat exchanger is permitted to operate The schedule Available 100 will allow the device to operate year round 6 Input the effectiveness of the fixed plate heat exchanger essentially how efficiently the heat exchanger recovers energy by clicking Effectiveness and entering the sensible effectiveness percentages at different airflows Click OK and then click Apply when finished Note To further refine the model of the energy recovery device the Options button can be used to define such items as parasitic energy consumers static pressure drop bypass dampers part load controls economizer lockout and frost prevention Stage Altos Energy Recowerp Transter Stage 2 Aitovka Enig RecowenTranater Extrade deck Renan a Schade ivan 100 75 Effectiveness Options Senate Type rene Cooling effectiveness at 100 afiow e6 x Direct efficiency T Cooling effectiveness at 75 aioe E s Direct cod schade OHT Heating otiectiveness at 1000 ations S Indvect eticiency T
267. e the Morning Warm up schedule as the Thermostat heating schedule 5 22 System Control Strategies Stat End Destenption Eaz tend rocitog Horth isy lt December Simdan ype Reduced pear C Filyos Day type Coaing design weekday 7 Comments pe A rejt and on weekends Jaruay December Sahada to Sunday 4 Stat End Deserption Eee naw cere hd Creen Month parny Simion ype Reduced pax C Flyes Day type Coaing design weet dey Comments pe Orly on wreekGays dare Ore day Jaruay December Sahaday to Sunday 5 1 ge necks Dg Derion Erai i sheds unda J Ahemaive 1 Degn Coorgdybb 5 F Heating dybub oF Retsive humadty 50 Themmostat Cooling dipon 5 F Above ground Heating dipai 5 F Floor mutipker E Roms persone 1 R oom ieam e z a ore 5 TRACE 700 User s Manual e CDS PRM001 EN Morning warm up for dual fuel applications llas Finally create a heating plant that consists of the gas fired furnace in the rooftop air conditioner and the electric heating coils in the VAV terminals Aatcoed Arc ded Waterco Waterco chev urtoy chiller untoy Electr Gsrfred 7 Add a gas fired heat exchanger and electric resistance heat to the heating plant Then use the entries on the Heating Equipment tab to finish defining each piece of equipment 8 With the gas fired heat Hlauieg lam exchanger displayed Ecuupment tag ei tred heat exchanger x Equipment cotegoy
268. e the efficiency of the chiller supplying warmer water to the tower will reduce the horsepower requirements of the cooling tower fans and increase the capacity of the tower m Increasing the evaporator AT can make a series chillerpiping arrangement appealing particularly for applications with helical rotary compressors or absorption chillers Related reading E Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN E How Low Flow Systems Can Help You Give Your Customers What They Want Engineers Newsletter volume 26 number 2 Sample scenario A central cooling plant includes a 500 ton centrifugal chiller The temperature differentials across the evaporator and condenser are 10 F and 15 F respectively Constant volume pumps serve the chilled water and condenserwater loops Modeling this scenario requires you to customize three existing pieces of equipment as illustrated on pages 3 35 and 3 36 a cooling tower a chiller and a constant volume pump Note Lowering the condenser flow rate decreases the full load energy rate of the cooling tower Use this equation to calculate the new eneroy rate LWT WBT LWT WBT where LWTq leaving condenser water temperature that provides a 10 F AT for example 85 F to 95 F WBT design wet bulb temperature LWTx new design leaving condenser water temperature that provides the desired AT a 20 F AT in this
269. e to edit information in any section that uses data from another alternative m Create based on TRACE 700 will create an editable copy of information from another alternative which will increase the Tile size and the calculation time However the user can edit information in any section that is created based on data from a previous alternative This option should be used when changes need to be made to a section but inputs similar to a previous alternative will be used m Create new TRACE 700 will create a new section with no data which will increase the file size and increase calculation time The user can Input completely new information in any section that is new This option should be used when changes need to be made to a section or alternative but inputs are not similar to the other alternatives Application considerations m he first step in creating alternatives is to determine how similar the existing alternative and the new alternative will be In general the more sections that use data from another alternative the better However if changes need to be made to a portion of an alternative Create based on if the alternatives are similar or Create new if the alternatives are very dissimilar should be used for the appropriate section s Two examples will be used to illustrate how to create alternatives in TRACE 700 Multiple ai handlers served by a chiller plant vs a large central al handler served by the same chiller p
270. e total Direct efficiency f x orp CF h Deect cod schectde fE Bpr x energy wheel is kadis SO swa E permitted to operate The Indrect col schede Ean bam I schedule Available 100 Stage 1 AatosAa Energy Recovery Transhes Stage 2 Ardoi Eneagy Recovery Teanales will allow the device to Tp ae La QA peecondtior Tyee Nerv detoudl oo Suprande deck Vertigon upvream artiy puea operate whenever it is Exhriide deck Sytem enas vl advantageous Schede vaiatie 100 6 Input the effectiveness of the wheel essentially sees how efficiently the wheel recovers energy by clicking Effectiveness and entering the sensible and latent effectiveness percentages at different airflows Click OK and then click Apply when finished Evaporative Cooling Type rare Drect cod schade E35 Indwect elieieney Fo Indirect col schedule E 25 Stage 1 Aroi Energy Reco Type Tasane Eride dack System ex Schedule CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 19 Total energy enthalpy wheel 4 20 System Design Options Note To further refine the model of the energy recovery device the Options button on the Create Systems Options tab can be used to define such items as parasitic energy consumers static pressure drop bypass dampers part load controls economizer lockout and frost prevention Additional Items When adding an energy wheel to an airside system it Is recommended that the mini
271. e used to treat the outdoor air and deliver it to the laboratory area This same air handler will also provide all cooling and heating to the laboratory area we TRACE 700 for exclusive use by C CDS TRACE700 Projects ASHRAE GZIRCIZ TR a2i5i x Fie Edt Actors View Optra L rais Temples Alernulives Setup Widow Help Seo gt R OF etkevn STAR TRANE Project Navigator 7 as E e reven tenas 1070172004 08 39 AM CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 73 Systems with 100 outdoor air 2 The cooling ventilation rate should be input as 100 and the units should be selected as Cooling Airflow The heating ventilation rate should be input as 100 and the units should be selected as Heating Airflow This can be done on a room by room basis on the Airflows tab of Create Rooms or for the rooms in general on the Airflow template in Create Templates Note For additional details on templates please refer to Using templates on page 6 125 3 If a minimum airflow must be supplied to the space then input the minimum airflow rate under the main supply airflow using the units of air changes hour cfm sq ft L s sq m cfm person or L s person By default TRACE 700 will calculate the supply airflow based on the loads for the space 4 f a VAV system Is being modeled the heating minimum airflow should also be input for the VAV minimum airflow rate 4 74 System Design Options
272. ead to undersizing of the heating coils and is not common design practice To view the schedule click Schedules on the Libraries menu and select Utilization as the Schedule type Here you can view the schedule and find schedules that will give more accurate results Typically selecting a ventilation schedule for the ventilation or copying the people schedule and making heating design 100 percent midnight to midnight will give more accurate results Load Design and Energy m The heating design day type for the ventilation schedule has hours that are not 100 percent The time that the heating load is peaking may be during one of the hours when the ventilation is scheduled off This tends to lead to undersizing of the heating coils and is not common design practice Load Design and Energy Note Because the heating design calculation assumes no solar loads and constant ambient conditions the hour of peak does not affect the conditions of the outdoor air Also this portion of the schedule only effects the heating design calculation Therefore 6 8 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes energy analysis other than the size of your heating plant and or coils and cooling design should be mostly unaffected E The input value for heating supply does not match the input value for the VAV minimum airflow This will cause erroneous airflow values In addition TRACE 700 should typic
273. eam of the valve to strain the condenser water before it enters the chilled water loop resulting In the name given to this method of free cooling Figure 3 11 Piping arrangement for strainer cycle free cooling cooling x tower X condenser loop chilled water loop cooling load Application considerations E Pumping cooling tower water throughout the entire chilled water loop increases the risk of corrosion and fouling Water treatment though costly can help mitigate this risk m Free cooling is only available if the leaving tower water can satisfy the entire cooling load limiting the effectiveness of this option Ambient wet bulb temperature determines the amount of free cooling capacity available from the strainer cycle cooling Capacity diminishes as the ambient wet bulb temperature rises 3 48 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Strainercycle free cooling m The cooling tower must be designed for winter operation Sample scenario A chilled water plant which includes a watercooled centrifugal chiller is piped to provide strainercycle free cooling Albani 1 lla After adding a water Couingplnt Eora pi 00 O He ecan cooled chiller to the cooling J ie w SECS plant Eqinment catagees watao chia a Hourly ambient wet bubat SCS Equpmentiype Careta A Thesemal storage 1 Choose the appropriate Seqercngiee Srce SSC twe noe i Capacity P
274. eason or heat the outdoor air to the user input heating dry bulb during the heating season before it is mixed with recirculated return air and delivered through a common supply fan WE Create Systems Dedicated Ventilation o 4 Select the control method Aamar 1 for the unit Because the iaig rhachis oar a ventilation cooling coil o E i dehumidities the outdoor Tinea rar _ Note For additional information air to the cooling supply Ceoing super ah cy bub i related to the other Control i Heating uppie an dy bub F i air dew point that is reset Coirassas o Methods press F1 and click based on room relative c Control Method humidity Optimize Dedicated Ventilstion Scheduler F Dedicated Venilstion Locations Supply Air Dew Point Cooingeod Avodstie 100 z Deck lb d Hestngcod Eroina Lei WI e used Cron avaisi 1 4 a Dpore Dedicated DA Ears ok Sehnat 5 Input the Cooling and Heating Design Setpoints In this scenario 65 F should be input for the cooling supply air dry bulb 55 F for the heating supply air dry bulb 65 F for the cooling supply air dew W Create Systems Dedicated Ventilation Akamara System description Dus Pgh As Hande Sige Zone Configuration Er Drehurrecditic stiors Ura Cirina mesthexd Epira Suppi Aa Chew Peri r Cosblirag Peating Deign Setpariti r Cacing Hasng Sepan Limits Cooling rupph air diy bab jis F Supply sr dry bulbs hig
275. eating Qs 5 500 Btu calculated by TRACE 700 based on heat losses E Cooling Ts 55 F Input by user or calculated by TRACE 700 E Heating Ts 100 F input by user Because constant volume systems supply the same airflow for both heating and cooling conditions TRACE 700 calculates the design cooling and heating airflows separately and selects the larger of the two airflows as the design supply airflow for the system This same supply airflow is then used for heating design and for cooling design Cooling 11 000 1 1 x SAx 75 55 SA 500 cfm Heating 5 500 1 1 x SAx 70 100 SA 167 cfm In this scenario the over undersizing on heating would be over undersizing 1 1 x 500 x 70 100 5 500 71 000 Btu This would indicate overheating of 11 000 Btu because the Space would need 167 cfm at a supply air dry bulb of 100 F to properly condition the space Rooms typically do not need as much airflow for heating as for cooling Oversizing therefore TRACE 700 User s Manual e CDS PRMOO1 EN Oversizing and undersizing Inputting the leaving cooling coil temperature will cause the same situations to occur as inputting the supply air dry bulb The relationship between the two inputs is shown below Supply Air Dry Bulb Leaving Cooling Coil Temperature Duct Heat Gain Fan Heat Gain draw thru fan configurations only CDS PRMOO1 EN TRACE 700 User s Manual occurs because there is too m
276. eating etectivenest at 100 aefiow fo x Eride dack fVentiston Schade fvedatie Effectiveness 77 Options Note Cooling Effectiveness refers to supply side ARI entering conditions at 95 F dry bulb 78 F wet bulb and exhaust side air entering at 75 F dry bulb 63 F wet bulb Heating Effectiveness refers to supply side ARI entering conditions at 35 F dry bulb 33 F wet bulb and exhaust side air entering at 70 F dry bulb 58 F wet bulb Additional Item When adding a coil loop to an airside system it is recommended that the minimum and maximum cooling supply air dry bulbs be set equal to each other to fix the value for the cooling supply air dry bulb This is suggested because TRACE 700 cannot psychrometrically solve for the cooling supply air dry bulb when an energy recovery transfer device is attached to the Return Outdoor deck Please read the FAQ and Oversizing and Undersizing sections of the manual for the ramifications of fixing a cooling supply air dry bulb TRACE 700 User s Manual e CDS PRMOO1 EN Coil loop for exhaust air energy recovery Total energy enthalpy wheel A total energy wheel is a revolving cylinder filled with a desiccant treated medium that is suited for transferring sensible and latent heat Heat transfer occurs when adjacent air streams usually supply and exhaust pass through the wheel in a counterflow arrangement The exchange medium inside the wheel collects sensible heat from the warmer
277. ecting a chilled water cooling coil using TRACE 700 output 6 80 Modeling for LEED Advanced Usage and General Modeling Tips Modeling for LEED USGBC s Leadership in Energy and Environmental Design LEED program updates Its products to closely align with the latest industry standards LEED version 3 the most recent version of LEED also known as LEED 2009 incorporates the latest standards such as ASHRAE 90 1 2007 and ASHRAE 62 1 2007 TRACE 700 has been updated to reflect the latest changes in ASHRAE standards and can be used to achieve LEED credits under version 3 Specifically TRACE 700 can model a building s energy use to determine its efficiency for LEED Energy and Atmosphere credit 1 EAc1 option 1 How to model the proposed building and baseline building in order to compare energy efficiency is outlined below Refer to Additional LEED credits on page 6 90 for a list of credits TRACE 700 may help to achieve Note If LEED version 2 2 is used the following guidelines still apply However version 2 2 references ASHRAE Standard 90 1 2004 not 2007 TRACE is compatible with both versions of the standard Ultimately it is the user s responsibility to ensure compliance with the appropriate standard s requirements Contact C D S support with any compatibility questions not covered in this guide Before you begin the TRACE analysis we recommend that you review the following LEED Reference Guide for Green Bui
278. ection needs to be edited and most of the airside inputs will be different in Alternative 2 As a result Create new will be used Note Templates cannot be Created New Project Nawigalor me TRACES TOD Ca DOS TRACE TOO Projects Tutorialtre tre Fie Eda Peer Whw Speer Liria Temples Aiii Sap Aier Heke Sa he OR er cae a ee Sa RF Project Nawigator Einter Propad Irka Bait ath nial AH Sees Valaat Idolos a Crercoe arire La nee Vaio 11 Tenplates Use Abbseratiens 1 fe Alen O Ara Be ign Rems lo Systems TAs ex A p UET Systems Selection Abemative 2 System description izten 001 VAN ve B aseboard Heating Venable Temperate Coratare Volume Venable Voluene Reheat IX Mr Flow Delad VOY wR anatra Sie Heaton Advanced Usage and General Modeling Tips Creating alternatives 6 133 To copy Alternative 1 1 Right click the gray bar labeled Alternative 1 then click Copy Alternative on the menu that appears A third alternative is created that uses the data from Alternative 1 Note The menu can also be displayed by clicking any line in Alternative 1 and then clicking Copy Alternative on the Alternatives Setup menu 2 To name the new alternative double click the project information for Alternative 3 to display the Project Information window and edit the Description field Note The Project Information window can also be
279. ed unless the night purge cycle is active 8 on The night purge cycle is an option for the airside system Click the Options tab of the Create Systems window and click Advanced Options 9 To make the night purge cycle available choose the custom schedule just created Create Rooms Airflows Altemative 1 Apply Adjacent air transfer from room Room description JExample room lt lt No adjacent air trans gt gt Templates Room Defaut 7 Cooling Internal Default x Heating Airflow Defaut Ventilation Tstat Defaut Type Constr Defaut Cooling Heating Schedule when Occupied 7 Infiltration Type Cooling Heating Schedule Available 100 Single Sheet Rooms Main supply Apply ASHRAE Std62 1 2004 2007 No Ausiliary supply Cooling ai changes hr Heating jo fachas Std 621 20042007 ClgEz eutn J EE Hoezen e Game DCV MinOA Intake None z Room exhaust Rate fo air changes Fl Ne O Schedule Availabe 10 x fo air changes VAV minimum fo ai changes hr Rate fo Clg Airflow Schedule avaiable 100 x Type TO To be calculated To be calculated Int Loads Direct efficiency U x Orpen OF Dereci cod schedule v ntable 100X Max outdoor oe 100 x Indwect etfcxrrcy r Schodde Avaasble 100 5 Indirect col schede Ey ohatle 100 r Stage 1 Aintodie Energy Recowerp T ranster r Stage
280. ed Dar ireira screen Wedd yina Won bi hurri A ari Options Create Systems Options Abematrve System description Penson x Singin Zone Z Evapceative Cooing Ecorneuner Type Nore E Select Ventilation downstream Dieci oicierey y if the device is located in the outdoor air stream and Indwect elficiency Indroct col schedle Seon SCY downstream of the optional ventilation cooling coil Type Heat pipe enas SA tampering Select Return outdoor air Supside deck Rodan 7 addoce on dowrstioam B downstream if the device is Stage Aa tows Energy Recover Transiter located after the mixed air stream downstream of the main cooling coil Schedule avondale 100 TRACE 700 User s Manual e CDS PRM001 EN 4 Select the exhaust side deck for the device In this case Return outdoor air upstream will be selected as the exhaust side deck The heat pipe will be used to precool the mixed air stream before it enters the main cooling coil Note If the proper airstreams are not selected for supply side and exhaust side decks of the energy recovery transfer device then the unit will not function correctly or may not function at all 5 Choose the schedule that describes when the heat pipe is permitted to operate The schedule Available 100 will allow the device to operate year round 6 Input the heat pipe effectiveness essentially how efficiently the heat pipe recovers energy by clicking E
281. ed as Cooling Only Design or uses an internal loads schedule People Office for example Available 100 or another appropriate schedule should be selected instead Also be sure that if a fan schedule has been input other than Available 100 that the actual system has the ability to turn off the fan based on time If the fans cycle in conjunction with driftpoints then a fan cycling schedule should be used instead found at the top of the screen If the fans turn off for a specific time period regardless of the temperature In the space a fan schedule should be used To view the schedule to verity accuracy click Schedules on the Libraries menu and select Utilization as the Schedule type Coils tab of Create Systems This tab should rarely be used but can be used to remove or schedule coils on and off based on time If a coil needs to be removed it is typically best to schedule the coil off instead of zeroing the capacity For most cases It is strongly recommended not to zero out a coil or schedule it off For example if the reheat CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 173 Altering a load design file for energy analysis coil or main coil are zeroed or turned off in a VAV with reheat system the design and or energy analysis calculations will be incorrect In this system the reheat and main heating coils are actually the same coil the heating coil in the terminal device Main is u
282. ed from the Rate Structure Library Description list The individual Defined rates also known as definitions can be found below the comments section of the rate structure ae E Eare a o e AR Minimum demand Fal adea ems Ne Dekeiion The definitions tell the program what values to use during the different parts of the economic calculations TRACE 700 will not calculate costs for a Utility ne Fie View Opora Window Heip electricity water and so on YF OTa ste V oerisy B47 Oe unless a definition has been haso created in the selected rate Eo 3 y structure Minium chage 3 To create a custom rate structure click New Structure A new Rate Structure library window will open with a default rate structure name in the Description field CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 151 Creating utility rates w Library Template Editors alal x Fie Vew Options Window Help POTEa te V oer is eer TeHeasA7ReE TRANE 4 In the Description field delete the default rate structure name and enter a name of your choice Avoid using any punctuation in the name r Plate Defintion Deterigtion Nother Wisconsin Utity Rate 4 xj Uy Eectne demand Minium charge 5 Click New Definition to start defining the rate structure Fem Forty gems Pi me 6 Select the utility that you ajgjxj would like to define fir
283. ed of denser materials such as brick Knowing how quickly the target temperature In the space can be achieved lets you minimize the length of time that the HVAC system operates before the occupied period begins Starting equipment as late and stopping it as early as possible based on scheduled occupancy ambient conditions and the thermal characteristics of the building can yield significant energy savings without sacrificing comfort Figure 5 3 Comparison of occupancy and operating schedules equipment enabled equipment operation with optimum start stop scheduled occupancy 12 a amp i 6 a m 12 p m 6 p m 12 a m Application consideration m Use a building automation system BAS to monitor and control the entire HVAC system Ideally the BAS should be capable of learning from previous experience so that it can optimally start and stop equipment daily 5 6 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Optimum start and stop In the Library Template Editors program 1 cy Create a new Utilization schedule to define when the supply fan operates from 6 a m to 6 p m daily for this example Make the Heating design schedule 100 percent midnight to midnight 2 Create a second schedule that tells the program when to search for an Optimum start time for the supply fan in this case from 6 a m to 7 a m on weekdays only CDS PRMOO01 EN TRACE 700 User s Manual Sample scenario T
284. ed to be input The Single Sheet tab paired with the data from the templates can be used to input all of this data Because this is the first room to be defined with the templates it is usually recommended that the individual tabs be checked to verify the inputs for the space 10Now that Office 101 has been created the other offices in the building can be modeled using the same set of templates Remember templates for each type of room offices hallways restrooms and so forth should be created rather than one set of templates per room entered In Create Rooms In a typical TRACE 700 file templates for the other types of rooms conference rooms hallways and so on in the building would now be created In this scenario only offices will be modeled A sample room will be input to show how to apply the templates The room is 1 500 ft2 has a flat roof one east facing exterior wall with 30 percent glass and is fairly typical of the other office spaces Amaire Note When the Room J Room descaghon Oce 101 P p template is selected many Template 8 Width o payme an om oO of the values such as i f fo a fe Internal loads and Airflows Zas will populate based on the Wal inputs from the Internal Deserpion Length It Hegti it Dene M p i Load Airflow Thermostat and a pk R Construction templates aiziz Anemaive 1 Note This building does not have ooo Il any skylight
285. ee cooling can be achieved with other piping arrangements depending on the operating characteristics desired Figure 3 9 Chilled water plant with plate and frame free cooling distribution condenser water loop plate and frame heat exchanger When the ambient wet bulb temperature is low enough the heat exchanger transfers heat from the chilled water returning to the evaporator to the condenser water returning from the cooling tower Precooling the chilled water before it enters the evaporator lessens the cooling burden reducing the energy that the chiller uses Application considerations m Adding a heat exchanger to provide free cooling increases the initial cost of the system The additional pressure loss also raises pumping costs m he ambient wet bulb temperature determines the free cooling capacity of the heat exchanger cooling capacity diminishes as the ambient wet bulb temperature rises Free cooling is only CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 43 Plate and frame free cooling Cooling equipment definitions in the TRACE 700 library include an approach temperature for a plate and frame heat exchanger the default is 3 F To model a different approach temperature use the Library Template Editors program to copy and modify an existing piece of cooling equipment Note TRACE 700 assumes that the capacity of the heat exchanger equals the cooling capacity of the chi
286. een the entering and leaving chilled water temperatures AT is larger for series arrangements than for other plant configurations Account for the larger AT when selecting cooling coils Related reading E Chilled Water Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRC016 EN E Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APM001 EN E Don t Overlook Optimization Opportunities in Small Chilled Water Plants Engineers Newsletter volume 32 number 4 Sample scenario An absorption chiller upstream and a centrifugal chiller downstream are piped in a series arrangement Each of these watercooled chillers has a nominal cooling capacity of 500 tons and a dedicated condenserwater pump The absorption chiller is preferentially loaded that is it starts first and handles most of the cooling load If the cooling demand exceeds the capacity of the absorption chiller the centrifugal chiller cycles on the minimum step of unloading for the centrifugal chiller The following illustrations demonstrate how to define the chillers Steps 1 6 and the loading strategy Steps 7 8 3 10 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMOO01 EN Series chiller arrangement W create Plants lla After creating a cooling Abemative 1 plant that consists of two Cooling plae Coclrgpirt O01 Heatrejectonnpe E5108 Cocirg tower
287. eers E 5 4 Opm Stan and S OD sea T ETR 5 6 HCN CAM OU esnan n n eed ot beces aoe 5 9 Fan pressure optimization for VAV systeMmS 006 5 12 Ventilation reset for VAV SYSTEMS ccccceeeeeeeeeeeee ees 5 14 Unoccupied ventilation night PUrge cccceecee eee e ees 5 17 Morning warm up for dual fuel applications 5 20 ehled wate rtesSet nenna N bee atededtead 5 24 Condenser water TESOL sia Heine theta a et 5 26 Load Shedding ECONOMIZEL ccccecececcceeeeeeeeueeeae scenes 5 30 DAV NOM MING anc cect iA E A moneiaslaas 5 33 Beman IMUNO prem eeeenertesnter arene eae Meat eres tee ttt nate errr es eaten 5 43 GLY Cyclin ena e a a 5 47 Supply air temperature FeSet cece ceeccseeeeeeeeeeeeeeenes 5 50 Chapter6 Advanced Usage and General Modeling Tips Common modeling mistakes s r 6 3 Rooms Tab oT Create ROOMS sickness ica 6 3 Roots and Walls tabs of Create RoomsS 00 6 5 Internal Loads tab of Create ROOMS 6 6 Airflows tab of Create ROOMS n c 6 8 Selection tab of Create Systems cence 6 10 Options tab of Create Systems cciceee 6 11 Temp Humidity tab of Create Systems 6 12 Fans tab of Create Systems e teiininioskenit oa 6 13 Coils tab OF Create SYSTEMS vcuesicsescthcaussacieadoran 6 14 CDS PRMOO1 EN TRACE 700 User s Manual Contents Cooling Equipment and Heating Equipment tabs Oe Ce Sy OA nsa a a 6 16 Base Utility Misc Accessory tab
288. eheat Cod mii Cochin plant 2 dedicated OA vind RHEE Canling Sytem WAH and DIOL G Opia Werdaton Cacing Col Eli Hesting plant 2 dedicated A un GRE Heating System WAH and DOSU E Optra venison Heating Cod Heating Equipment tab gas fired hot water boiler Aircooled unitary split system RAUC rooftop gas heat 20 ton scroll CDS PRMOO01 EN TRACE 700 User s Manual System Design Options Dedicated outdoorair systems 4 61 Scenario 4 A building is served by a fan coil system and a dedicated outdoorair unit that delivers conditioned outdoor air directly to the individual spaces The system level controller polls the fan coils and resets the dry bulb temperature leaving the dedicated outdoorair unit to avoid overcooling or overheating any room During the cooling season the dedicated outdoorair unit dehumidities the outdoor air to 55 F dew point and then if necessary reheats it just enough to avoid overcooling the room with the lowest sensible cooling load During the heating season the dedicated unit heats the outdoor air as much as possible without overheating the room with the lowest sensible heating load m Ihe system controller determines the current supply air dry bulb setpoint needed to avoid overcooling or overheating any room m VVhen the outdoor dew point is greater than the cooling supply air dew point setpoint the dedicated outdoorair unit will dehumidity the entering outdoor air to the cooling su
289. eling hints 2 28 Program Overview TRACE 700 User s Manual e CDS PRM001 EN General modeling hints Cooling and Heating Plants Modeling examples in this chapter Cooling and heating plant design and control Decoupled chiller arrangement page 3 3 Parallel chiller arrangement page 3 7 Series chiller arrangement page 3 9 Variable primary flow chiller arrangement page 3 13 Switchover control for chiller plants page 3 17 Thermal energy storage page 3 21 Cogeneration page 3 28 Direct fired absorption cooling page 3 31 Low flow chilled water systems page 3 33 Purchased chilled water page 3 37 Purchased district steam and purchased district hot water page 3 40 Free cooling and heat rejection Plate and frame free cooling page 3 43 Refrigerant migration free cooling page 3 46 Strainercycle free cooling page 3 48 Double bundle condenser heat recovery page 3 50 Evaporative precooling of condenser air page 3 54 Cooling tower with VFD page 3 57 Chiller tower optimization page 3 59 Domestic hot water E Domestic hot water assigned to a boiler page 3 62 Heat pump systems E Aijrto air heat oump system page 3 64 m V Vatersource heat oump system page 3 68 CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 1 3 2 Cooling and Heating Plants Ground source heat pump system page 3 72 Central geothermal chillers page 3 76 Variable refrigerant flow system page 3 81 Note Thi
290. em and the associated coil s drag it to the appropriate plant that is assign cooling coils to cooling plants and heating coils to heating plants as shown in Figure 2 13 on page 2 18 Note In some types of systems the same coil serves as both the main cooling coil and the main heating coil Examples include fan coils unit ventilators and watersource heat pumps TRACE 700 represents the cooling and heating functions separately as purple coils so that you can assign each coil load to the proper plant CDS PRMOO1 EN TRACE 700 User s Manual Program Overview 2 17 Performing basic tasks Figure 2 13 Assign systems to plants Project Navigator view gt Cooling System Fan Code Hale asorage he Coolng plant 001 E Man Couing Col f Cooler System PPVAY Clarina ot Hasra Spia Fari ot Hal Sloe E Wla reire Lice E Man Hasira Lol k gi Hasir Spele FPVAV latita E Man Hiashi Col Drag each unassigned system and associated coil s to the appropriate plant Define economics The TRACE 700 program calculates financial measures such as the net present value of annual cash flow internal rate of return simple payback period and savings to investment ratio To complete these calculations the program applies utility rates to the monthly energy consumption of the cooling and heating equipment determined during the plant simulation Entries in this section of the program describe various economic factors
291. emnainee 1 Syshem deserption asne Wate Source Haat Purp VAV wF toed Flow Shan Hesling Verntiahon acd Hears Create Systems Fan Overrkles Pils x Alemative 1 System description csHr 7 Water Source Heat Pump Aa Fan cycing schodue No tan eyeing Ovorides Ful Load Ful Load a im phe eet Primary Hydronic in heat pumo fan a _kwiCim Available 100 Secondey None w t Avodatle 100 Pedan None l lo kiw Cim Available 100 Cooling plants Ls a lias Ground source hes pump Ancocled Waterco Waterco Sd Ground source heat pump 001 untay chides uray o henaic Electric Garrod siitance h s exc Click Fie displayed chi ui Ick to save tne displayed entries p Dosing Eqpapmend Akemi 1 pay j Cooling plant Ground Soure Heat Pump Type WHP Coning torre a Hourly artar weet kah dhie F Cancel Thama Shit anges Hew Egi Twe GLAC centred ie 10 ECI TO wate Bape Unity hipt Accesso This entry defaults to Ground loop so that any excess heat from the heat pump is rejected to the ground loop This entry identifies the heating plant that will serve as a backup if the heat pumps cannot satisfy the load TRACE 700 User s Manual e CDS PRMOO01 EN Ground source heat pump system 9 Click Cooling Plant and Cooling Equipment Controls xj Geothermal Controls EE EN eet 10Choose the geothermal bone J otopa loo
292. ems Fan Ovenides i Akamata primary fan in the dual Sysbem desertion Buah Ar Hare Singe Zone path air handler rliai sit Mes Next define the cooling and heating plants represented by the dual path air handler system and the rooftop air conditioner 9 Add a new cooling plant and a new heating plant A Gr ct Ge to the Configuration a a wo Paine 6 m Doler Electio Garfred 10Drag the appropriate ER icons from the j Equipment Category section to define each plant 11 To finish defining this equipment enter the information from Table 4 10 on page 4 72 on the appropriate equipment tab CDS PRMOO01 EN TRACE 700 User s Manual abi 100 E L Awalabia 1003 las Cooling Plant 1 Chier Piani E E Watercooled chiler Heating plants kas Heating plant 1 Doler S Gasdeed boler For cooling use water cooled chiller and air cooled unitary For heating use boiler and gas fired heat exchanger To asap cqupmeri drag e OCOL mpra Gye wy oe System Design Options Dual Path Air Handler Split Dehumidification Unit 4 71 z Finally assign the coil loads of the airdistribution l PmE system to the proper cooling and heating plants Bat Cosin Prt hie Pl E Optional Werason Cooking Cod _Heww Sivitern 12Drag each coil in the Tass New el Plan Unassigned Systems I TAE eae New beat Plt Coils pane to the ey appropriate plant in the System
293. ensate drain pans evaporative precooling systems require additional care to ensure proper cleanliness and operation Sample scenario A 60 ton rooftop air conditioner cools a building To reduce the energy consumption of the air conditioner an evaporative precooling media is used to lower the temperature of the condenser air stream The effectiveness of the evaporative precooler is rated at 60 percent The illustrations below and on page 56 demonstrate how to add a rooftop air conditioner to the current project Steps 1 3 and equip it with evaporative precooling Steps 4 5 Note Evaporative precooling effectiveness defaults to 60 percent for all ai cooled equipment in the Cooling Equipment ibrary To change this default value copy an existing piece of cooling equipment and modify it using the Library Template Editors program Git Arcod untay 001 Heating plants lia Heating plant 002 g Now Cig Plar New Hig Plar 2 Eat xj I i Rore Utility Mince Accessory CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 55 Evaporative precooling of condenser air Next define the capacity of the rooftop unit 3 Enter 60 tons as the cooling capacity Cockers piane 001 Eqipnert tog Acoto Una 7 Equpmert catego Arcooed utay SY Eqamerttype Desa orccokdutay x Sequenang type Seige Finally add the evaporative precooling option to
294. entilation unit ll Next define the cooling and heating plants represented by the VAV system and the rooftop air conditioner 10Add two new cooling plants and two new heating plants to the Configuration pane 11Drag the appropriate icons from the Equipment Category section to define each plant 121o finish defining this equipment enter the information from Table 4 8 on page 4 61 on the appropriate equipment tab 4 60 System Design Options Alemetrwe 1 Syshem description VAH and DOAU Vanatle Volume Reheat S005 Min Flow Delak r Design As Tempanunae r Direcvindrect Dehumidiication Methods System Simdstion ork Cooling supply Maw F Type Mere Ma Masira toom relative husnidity 8 fa x Max 4 Man cooling cod marmaum allowable Inawng E when trotting a chiled water cod downward Mnf Variabla Fan Speed foe capacity corirol System Simulation ory Maf F Number of tan speeds ine ooa wf Percent sitlowatkweeed Percent alow of mechan speed T Hundar Design humidity ratio diference TT gani Mrara 100m relative hardly 30 x Create Systems Fan Overrides Adematrve System description VAH and DOA gt Variable Volume Plehest 30 Min Flow Detak Fan cycling schedule Cycle wath occupancy Awaiable 100 Avadable 100 E E of ot Ba Codey oie aircooled chier Biookd Aincosled Waleo Wateren 8 Aircooled chiler 1 er undaty Ell Cooling plant 2 ideckoated 014 u
295. enu could be used to base the Lo J o templates for Alternative 3 on Alternative 2 E raye bemplates fot tus albematrrs baced on Adernatied 1 ne TRACT 700 C CDS TRACE7O0 Projects Completed Tutorial 42 720 Fle Edt Actions View Options Ubris Templie Alermative Setup Window Help Seo DR ar kaereave SRR BP Project Navigator Central AHU La Gosse Wiscorari La Doses Weceras Une Akernative 1 11 Templates Based on Abemstive 1 a mel Use Atemstive 1 zj ae Dhebenpien E Croom a Tonglasi e Intemalioad i Caron z e Aria m School bail Deiete Tharisital 0 Chefsult Z Ahi kha Coonetuction Chet nl S __ a _ CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 135 Creating alternatives Additional items 1 If the templates rooms and systems sections of an alternative all use the same data as the previous alternative then the design and system sections of the calculation will not need to be recalculated This will result in a smaller file size and much quicker calculation time than a completely unique two alternative file 2 fa user tries to edit a section that is using the data from a previous alternative the user will be able to view the data but no changes will be allowed To make changes the user will need to either create the section based on a previous alternative or create a new section
296. er water temperature for the chiller The default for most water cooled chillers in the TRACE 700 library is either 55 F or 65 F Fou When finished return to the TRACE 700 project to add the newly created equipment to the cooling plant 5 28 System Control Strategies Condenser water reset Temperature based condenser water reset Use the procedure illustrated below when the speed of the tower fans or the position of a tower bypass valve controls the entering condenserwater temperature ain x Fie View Options Window Help POTALA ZiT Eia cemana TRANE Cooling category Water cocind chaer i Commens CHE CENTRIFUGAL CHILLER t 170800 TONS Equement ype Stage Certntugal 1 Qose Cosina categane fix ater cocted chiler Comments Based on CVHE 170800 TONS wth Equpmani hga Carisiugs chie eviower bypacs 3 Cancel osing pe Pomaty Senora a Power condumed eE joma Ghareland Ambient modiip stion eme Arb Mod x Hone a ww aan Chiki aiii Lemp Dzy inara ua F Cifeerce fo F Cordances temp Despensa 05 fF Mireumopecing 5 4 Ages condere heat Toelersnoe lype Heat racian eaman TRACE 700 User s Manual e CDS PRM001 EN 9 Use the Library Template Editors program to customize an existing piece of cooling equipment 1 is Open the Cooling Equipment library and choose the Equipment type that best matches what you want to model Click Copy Repl
297. er assigned to a boiler on page 3 62 dedicated outside air systems refer to Dedicated outdoorair systems on page 4 45 etc m The Building Cool Heat Demand report shows airside coil loads from the System simulation The Plant Load Summary report 3 76 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Central geothermal chillers shows all loads assigned to the central geothermal chiller system including all end use components m Central geothermal systems may have additional pumps Be sure to include all pumps within Create Plants If additional pumps are needed they may be modeled as accessory pumps within Miscellaneous Accessories The bidirectional cascade system employs condenser and evaporator energy transfer pumps which are modeled as Miscellaneous Accessories in this example Related reading E Central Geothermal Systems Application Manual Trane literature number SYS APMOO9 EN Sample scenario A central geothermal system uses two RIWD chillers in parallel each capable of providing 200 tons of cooling and 1870 Mbh of heating This system is set up as a bidirectional cascade and uses two energy transfer loops with pumps to transfer energy between the chillers during simultaneous cooling and heating Figure 3 21 Two chiller bidirectional cascade central geothermal system Le condenser energy transfer pump from borefield DD to borefield P evaporator energy Q transfer
298. er pump on the Heating Equipment tab 9 r Assign the heating coil loads to the heating plants Note To further refine the model of the desiccant dehumidification device the Options button on the Options tab of Create Systems can be used to define such items as parasitic energy consumers supply side design air conditions coolant types approach temperatures heat source temperatures economizer lockout and so on Cooling plants Mas Cookers part 001 Heating plants A wm of ft Aatcoed Ancoked Waterco Waterco it chaer urtary chiller und sry lla Heating plant t1 main system Boder man spiten rs Hot wate pumo How Cig Plori Mas Heating plant 2 erence aed pa New Hio Pn Wae Electric lee Gas teed heat exchanger regenerates awot he aE La As cocied Cookery Pumps Thermal Coriano tomer thot age Enoy Mgmt llas Cookery plart 1 fs Heating plara H1 man site OC Heat System System 001 Mar Heating Cot B Retest Col E Prehew Coa Unassigned systems and atte taet aan associated coils appear in i this pane To assign a load and or system drag the relevant icon to the appropriate cooling or heating plant at right The Stage 1 desiccant regenerator regenerates the solid desiccant Additional item When adding a desiccant subsystem to an airside system it Is recommended that the minimum and maximum cooling supply air dry bulbs be set equal to e
299. er rejects less heat to the cooling tower Flow modulation can be accomplished with a variable frequency drive on the condenser pump or alternatively could be accomplished by varying the temperature of the water entering the condenser by installing a cooling tower bypass Inset A Figure 3 12 Heat recovery with a double bundle condenser heating load 95 120 F auxiliary heat source cooling tower cooling condenser heat recovery condenser Ss hot water pump tower bypass valve a condenser water pump with variable speed drive evaporator cooling coda cna Ware purap Inset A tower bypass cooling load As the water temperature returning from the heating load falls the variable frequency drive modulates the condenserwater pump to decrease the flow of water through the cooling condenser and tower If a cooling tower bypass is used the bypass valve modulates to divert a greater amount of water directly back to the cooling condenser 3 50 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Double bundle condenser heat recovery With less heat rejected outdoors more heat can be collected by the heat recovery condenser The amount of heat recovered depends on the extent to which condenserwater flow is reduced Given the characteristics of the application and of the chiller selected the heat recovery condenser can produce hot water ranging from 95 F to 120 F Appl
300. erating conditions 6 24 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Frequently asked questions Plainly put the combined energy efficiency that a SEER provides is not detailed enough information for TRACE 700 to calculate accurate energy consumption data on an hourby hour basis Q How is a rooftop modeled A The answer depends on the type of rooftop that is being used Most rooftops fall into one of three categories constant volume variable volume and constant volume fan with variable volume terminal devices For a constant volume RTU there are three airside system types that are typically used single zone variable temperature constant volume and terminal reheat The single zone and VICV system types are very similar They should be used to model RTUs that have one heating coil one cooling coil and a constant volume fan that serves one or multiple spaces For the single zone and VICV system types to serve multiple rooms in TRACE 700 a zone must be created in Assign Rooms to Systems and all rooms served by the RTU must be assigned to that one zone Each zone assigned to this system type or each room directly assigned to the system type will be modeled as a separate RTU Please refer to Zoning of rooms on page 6 47 for more details on zoning with SZ and VICV systems The terminal reheat system type has one system level cooling coil one system level heating coil and multiple zone
301. erature CDS PRMOO1 EN TRACE 700 User s Manual Cooling and Heating Plants 3 11 Series chiller arrangement The sequencing strategy for the chillers is defined at the plant level 7 Select Cooling plant 001 and click Sequencing 8 Reading left to right the equipment order shows which chiller starts first second and so on when a cooling load exists By default the program sequences the chillers in the order that you created them To change the displayed sequence delete each entry and pick the desired equipment tag from the list When the desired sequences operators and so on have been defined click OK to exit No further entries are needed unless you define two or more equipment sequences Click Cancel to exit if no entries have been made For examples refer to Switchover control for chiller plants on page 3 17 3 12 Cooling and Heating Plants Series chiller arrangement Abomative 1 Equpmert Category A wm ot ae o Sa e a tae Pot wend m amet Wate Boder Electi Gasrtred taos he resiitance hest enc GP Condenser water pump Heina plants ge a2 ma a la Heating plant 002 E r i a Delete Arcod Cooley Purge Thermal ia Corddercer lower thot age Enay Mgmt 7 am To stagh equement dag the deteed equement calegory lo the Coniguzshon bee zj Hoe Enie soquenong crion n kest bo lyst andat The frit ciena mat wil be used TRACE 700 User s Manual e CDS PRM001 EN
302. ers through the templates will significantly reduce input time Note TRACE default glass U values were created using center of glass values If assembly U values are desired users may override the existing glass U value with an assembly value or they may import a Window 5 assembly glass type For additional information on importing Window 5 data please consult the TRACE 700 help files by searching Import Glass Note TRACE only allows Shading Coefficient values to be entered SHGC values can be converted to SC by dividing the SHGC value by 0 86 ASHRAE 90 1 2007 requires the baseline building fenestration to not exceed 40 percent refer to ASHRAE 90 1 2007 Appendix G Table G3 1 for the requirement definition If the proposed building has greater than 40 percent fenestration the baseline building fenestration will have to be adjusted to 40 percent For a detailed explanation of how to apply this requirement consult the ASHRAE 90 1 2007 User s Manual If an adjustment needs to be made in the baseline alternative consider making the adjustment through the Component Tree view refer to Component Tree view on page 2 8 for additional information Define lighting power densities The same method for defining the lighting power densities in the proposed Building Area Method or Space by Space Method must be used in the baseline Refer to Section 9 of ASHRAE 90 1 2007 for the mandatory requirements plus a description of the
303. es Bar utes Meccelan ous atcessones OF Systems Op Options BY Desci Vert F Temperature Humidity DO Fas E co Finvea Abm amp Pocpie L Lighting e Foote 2B Mircelareous Load fF Puttions Pa TRACE 700 User s Manual e CDS PRMOO01 EN Other workspace elements Menus across the top of the main TRACE 700 window organize the commands that help you manage and work with the analysis projects A toolbar directly below the menus provides one click access to many of these commands Holding down a toolbar button or highlighting a menu command displays a brief description of its purpose in the status bar at the bottom of the TRACE 700 window For additional information consult online Help Figure 2 5 TRACE 700 toolbar Project Tree view Add a new alternative Create a utility rate Add a floor 7 Create recurring and or Add a partition additional depreciable cost Add miscellaneous internal loads Shoarsunmao normadan Add a wall for selected room zone or Add a roof system rE a C a a t S mw ae a Create systems Calculate results Assign rooms to systems g y View results Create a room Start Library Template Editors program Add a watercooled unitary air conditioner Add a water source heat pump Add a water cooled chiller Add a boiler Add an air cooled unitary Add electric resistance heat air condiioner i Add a gas fired heat exchanger isle Seca es oa oF
304. etermine the required outdoor air for each zone This is determined by dividing the Breathing Zone Outdoor Airflow by the Zone Effectiveness This process must be completed for each zone that will comply with Standard 62 1 Now that each zone level ventilation requirement has been determined the system level ventilation can be calculated which is also known as the Outdoor Air Intake for the system This procedure varies for different system types For single zone systems equation 6 3 Indicates that the ventilation requirement will be identical for both the zone and the system because they are one and the same For 100 Outdoor Air systems also known as Dedicated Outdoor Air systems within TRACE equation 6 4 is used which sums the zone level outdoor airflow to derive the system level For multiple zone recirculating systems I e variable ai volume reheat systems sections CDS PRMOO01 EN TRACE 700 User s Manual System Design Options 4 91 ASHRAE Standard 62 1 6 2 5 1 through 6 2 5 4 are used to determine the required system level ventilation Once the system level ventilation has been determined the procedure is complete Application considerations E ASHRAE Standard 62 1 may not be as stringent as local codes You can create new airflow requirements using the Internal Loads and Airflows library m The minimum discharge airflow for each space is critical in determining the system level ventilation requirements when using ASHRAE S
305. etermines the type of energy recovery transfer and the basic configuration In this case Fixed plate HX parallel SA tempering Figure 4 9 for Inset A refer to steps 1 through 6 in Sensible wheel on page 4 34 for Inset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 for Inset C refer to steps 2 through 7 in Coil loop for exhaust air energy recovery on page 4 8 Related reading Airto Air Energy Recovery Engineers Newsletter volume 29 number 5 Airto Air Energy Recovery in HVAC Systems Applications Engineering Manual Trane literature number SYS APMO003 EN Sample scenario To input the type of heat recovery in Figure 4 8 Inset A we will model a laboratory that is conditioned by a variable volume reheat system To reduce the amount of reheat energy required a fixed plate heat exchanger will transfer sensible heat from the return air stream to reheat the supply air stream after it leaves the main cooling coll Abemative 1 Syitemdeccipion Las sss Evaporative Cocing Type Hone bel Direct elficiency x Deectcodechedue vim Irakek altcency E indwect cad ehedat On 0 i o Silage 1 fa fenfun Ereng Petina T ranite Silage FAri E rig Fairs T aneha Foomd plate H pia 54 barir Tiga Home default T Cle onip iuri oure cod loop aeir CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 23 Fixed plate heat exchanger 2 Amessage will appea
306. example 3 34 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Low flow chilled water systems Use the Library Template Editors program to modify existing definitions for a chilled water pump cooling tower and chiller 1 Gd In the Miscellaneous Accessories library copy an existing pump Use Var vol cond water pump for this example Rename the new pump and add comments if desired 2 Reduce the full load energy rate by 10 x where x is the temperature difference across the evaporator in this case 20 Save your entries 3 In the Heat Rejection library copy an existing tower for example Eq5100 Rename the new tower and add comments if desired 4 Decrease the full load energy rate by 95 F 78 F LWT 78 F This formula is explained on page 3 34 5 Modify the design characteristics of the tower to reflect the new range 15 F and flow rate 2 gom ton 6 Cooling towers in low flow applications often use variable frequency drives If desired define continued on page 36 CDS PRMOO0O1 EN TRACE 700 User s Manual a Low apond onerg i i Fiir bull kiil alaiz Fie Vew Options Widow Help POTa te Ree ly eEA CHO my ADS TRANE E Miscellaneous Accessories Library Category fweater J Unloading curve Venable Vol Condenser Water Pump ve Equipment type va vol cnd water pumo Variable Vol Condenser Water Pump Comments Conderamt water
307. f operating a load shedding economizer auxiliary heat heating 600 economizer ilo cooling cooling 500 cooling and heating demand MBh 400 300 recovered heat 200 chiller 100 I SLH outdoor air 0 y 2 4 6 8 10 2 4 6 8 10 ii noon ii midnight For coordinated operation the same controller governs the economizer and the heat recovery equipment An initial decrease in the heating demand prompts the controller to turn off the auxiliary heat and rely on recovered heat to satisfy the perimeter loads Further decreases in heating demand Indicate that less 5 30 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Load shedding economizer lz To model the cooling and heating plants in this example 1 Add a water cooled chiller to the cooling plant If desired replace the generic equipment tag with a more descriptive name 2 Waterside heat recovery applications typically include a backup source of heat For this example add a boiler to the heating plant heat is needed so the controller modulates the economizer dampers open The chiller responds by unloading to reduce the amount of recovered heat available If the economizer is fully open shedding as much chiller capacity as ambient conditions permit and the heating demand drops further the cooling condenser rejects the unneeded heat to the cooling tower The control sequence just described operates in reverse when
308. f the condenser coll As the condenser fans draw air through the precooler water contained in the wetted media evaporates cooling the air stream before it enters the condenser coil The temperature drop resulting from the evaporative process increases condenser capacity and improves the overall efficiency of the machine The extent to which efficiency is improved is determined by the difference between the wet and dry bulb temperatures and also by the effectiveness of the precooling coil refer to Figure 3 13 Figure 3 13 Effect of evaporative precooling energy efficiency ratio EER 30 percentage improvement 20 approximate gE 2 3 a x a m capacity Btu h 0 10 F 20 F 30 F 40 F 50 F wet bulb depression dry bulb wet bulb 3 54 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Evaporative precooling of condenser air lz First define the cooling plant as a rooftop air conditioner 1 Drag the air cooled unitary icon to the cooling plant 2 If desired rename the plant icon as Rooftop Unit If you prefer you can rename the equipment tag from the Cooling Equipment tab Application considerations Adding an evaporative precooler increases water usage which may be a significant cost consideration in dry climates Condenser fans must sustain higher static pressures when an evaporative precooler is present Consult the manufacturer to determine fan capabilities Like cond
309. ffectiveness and entering the sensible effectiveness percentages at different airflows Click OK and then click Apply when finished CDS PRMOO0O1 EN TRACE 700 User s Manual W Create Systems Options ool Note If both stage 1 and System description Piestesart Sings Zone Petros p stage 2 energy recovery Te Nene E Twe h transfer devices are given z 0 i enm MELESE i ones the same exhaust side deck Dies cod ochadue Avai 1 0 Max outdoor aie T ieee me then stage 1 will be Inddeect cod schedule Evai 1005 upstream of stage 2 p Sage ZArg Ensi Facia Tianhe Howe pleiet Sedge un Ti Stage Aa toni Energy Pecoweta T rancler Type rien papa bimi DA hampers Type Gupaide deck Fan mier ae dewrninan 4 Fehetacle eck Petan Fiia Aa i Sebel venkat 1 Etiectvensss_ Options m Select Return outdoor air upstream if the mixed air stream recirculated return air after room exhaust and system exhaust plus the ventilation is used as the exhaust side m Select Ventilation upstream if the outdoor air before it enters the dedicated ventilation unit is going to be used as the exhaust side This selection should only be used in combination with a dedicated ventilation unit Create Systems Options Abemetrve System description Penara r Evaporative Cooling Type None bed Deectetfciercy f a Stage Altos Energy Recowerp Trancter OO OYA
310. file name m Only custom library members used in the file will be transferred with the archive file m The archived file will be located in the same directory in which the project file trc is located aixi Note When opening a Lokit ca macero Ee TRACE 700 Archive File filename TAF the utility will automatically extract the TRACE 700 project file filename TRC and import the custom library members If library members with the same name exist TRACE 700 will prompt the user Advanced Usage and General Modeling Tips 6 175 Archiving and un archiving instructions storing library members with project files Printing used library members IEZ To print all library members used in an alternative 1 Open TRACE 700 and the desired project file 2 Click Entered Values on the View menu 3 Select the alternative containing the library members you would like to print and select the Library members box 4 Click Print to print the library members or click Preview to preview them When submitting an analysis for review it is often necessary to print out all schedules construction types equipment and so forth used in the file The Entered Values section of TRACE 700 allows users to print all library members used in a file me RACCA FOO bor exclusive use by ay TRACE TOD Projects Tulonie tine Meir Bi T Fean rion System inama D Feom asigmeni be j T Pisi information F Lironi 3 E
311. fine each plant Rename the cooling plant as WSHP and the heating plant as Backup boiler llas Water source heat pumo Water source hast pure 001 Arcod Waterco Water lt o 4 Select the cooling plant and wiy he tay og Pre wierd i rr o iow Clg Plant click the Cooling M aaa Pinay are te ma E i Elects Gsrfred gt lls Backup bo a Pas quipment tab resitance hast exc Dose 001 5 Choose the watersource heat pump that best matches the target T p a es ooir plant water Sauce Hew Pump Heat repoa performance apne lag iater source heat pume 001 Typ esHe Cici lireta ema Equpmert category winter hinnie heel purge Hourlip abian meat Bulb diia 6 Enter the full load c Eqaomertivpe woarerSouceHP Highttic D F Thomslsieraga consumption of the pump senenge sre i Tea i Hou pump koop na oraga E that serves the common water loop the primary chilled water pump in this case Capeacaly fiz gation 3 70 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Watersource heat pump system 7 Click Controls to assign the excess heat from the common water loop to loads served by the heating plant identified as the energy source Note Do not remove thermal storage The water loop is modeled as a special thermal storage type in TRACE 700 Removing the thermal storage eliminates the water loop f
312. for the alternative 3 Itis not possible to copy the data from an entire alternative to another alternative unless the source alternative is completely unique If one section of the source alternative uses data from another alternative the entire alternative cannot be copied However individual sections of the source alternative can be Used or Created based on For example the entire Alternative 3 could not be copied to Alternative 4 in this Scenario only Alternative 1 could be copied to Alternative 4 Alternative 4 could however have templates based on Alternative 3 because the templates for Alternative 3 are unique 4 When editing information always be sure to check the upper left hand corner of the screen to ensure that the correct alternative is being edited 5 For additional details on how to use templates from Scenario 2 please refer to Using templates on page 6 125 6 f more than 4 alternatives are desired refer to Creating a new file based on an existing file on page 6 179 for information regarding creating additional alternatives 6 136 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Creating alternatives Creating schedules In this example a schedule for the people in an office building will be created The design options of the schedule will be as conservative as possible and the energy analysis portions of the schedule will be as representative of the actual occupan
313. for the folioweng Desy phase efiliabon venison reheat mrar ad al system smdan ochadi LL A percentage of 0 prevents duty cycling if any of these conditions occur when the duty cycling schedule is in effect m Room dry bulb temperature exceeds the thermostat set point for cooling by more than 3 F m Room dry bulb temperature is more than 3 F cooler than the thermostat set point for heating m Room relative humidity exceeds the design target by more than 10 percent not shown in above picture 4 On the Options tab click Advanced Options to display the optional airside control strategies Stage 2 Altos Eneegy Recower Tranater Type Nore deia d r Stage Atos Energy Recover Transier None l tagi 5 Select the custom schedule that was created in Step 3 xj 6 Enter a panem length to ee sie om hype set the duration of each a AEN Oe em duty cycle 60 minutes in Schedules Man cooling ton this example Discriminar contol ow ra Manesa Might purge ous Anday tan ro 7 Set the maximum off time Opler stot am cy z o Pomet to define how long the fan inaheup as ra ton can remain off during a dut pees gt Sister Level Verdision Ores f 9 y In pind schedule Duty Cpcing 5 7 Aie Gan ol come reer ve E cycle In this case the fan Ga A T can remain off for up to Maumee 0 7 ames T Foos schaerutendside om daegee 20 minutes but not longer CDS PRMOO01 EN TRACE 700 User s Manual
314. g coil the surface area of the coil must be calculated This is often determined by using a maximum allowable coil face velocity Assuming a maximum face velocity of 550 ft min the face area of the coil is Coil Size 24 227 cfm 550 ft min 44 05 ft2 Assuming that in this example the maximum nominal coil height is 4 5 ft to fit into the space for the air handler the resulting finned length is 9 79 ft 44 05 ft 4 5 ft rounded up Those dimensions equate to a nominal coil height of 54 inches and a finned length of 118 inches o Trana Official Prit Saedection System Puy p algaja E Ph Cat Podst Vew Fame windsw bhi 3 La 3 honon ie amp m da L 2 2 al Products In Upe F toning ca Geral E ELEL i EF Rum Messages These ann Be iuri mesages ahurra fiar l ran hor Eha diri j Froduct In Upe F Cening cea E ue E CLOLe 1 Coubhe Chek to Jurnp to Fiski D Warming Li Diagneetic O Critical Clana m Cod ote a R Cod 2 Pig baked because The requegbed coid eater fin bape ip mot radade on thin cod type al Sata a ink vical Car ee PATO he here a ape Capacity an in aan condiion ad Diki Wale SAR Cod F Rest Lede beau The igea ers eba br pyr r wed rw vaeLadobes cei bhat coal bpp H Td waa SWIATA Col 2 Ripus beled becouse The mberg nar im the cold waha fd apere cua penae erip i een ie ne la cu j Caii Wiebe SOW Col 4 Reve beled becu
315. g templates 4 Finally for the Baseline alternative set the Standard 62 1 2004 2007 inputs in Create Templates and Create Rooms to No to prevent the program from running the Standard 62 1 2007 zone calculations again aiz j Adhacert aie trarafer from room s iNo afaceri as hanss omen st Anay supply Roem Once ire gt cooing ft Intend lice Heating E T Veriishon Appl ASHRAE Sda 1200472007 no A hg enmia Faam Y 5 Set the cooling and heating ventilation inputs to the cfm sq ft rate from Step 3 6 Go to Create Systems click Advanced and set the System ventilation flag to Sum Room OA Regs in the Baseline alternative to prevent the program from running multi zone calculations of Standard 62 1 2007 CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 89 Modeling for LEED 6 90 Advanced Usage and General Modeling Tips Modeling for LEED Create Systems Advanced x System description Baneline Syibsn 5 Speier bees Varigble Volume Reheat H Min Pipa Deist Cra Suppi ben mao boosii igy isiu Lari eration peste Piata mey O 4 i Fan dining ishod Eta Supply air path duct location ithe Fisum ar path Deea x Bleek cacing afier i Cooley cial sony mahad Hock Cooling colllloc ation Veniilstion deck location Aetunlides Deck i Spstem ventiston Hag App ADHAT Sid 621 200 S007 People dverging D vz ASHPAE ShI Maw Ver
316. ge 6 137 Energy meter Verify that the energy meter for the miscellaneous equipment has the correct utility type selected usually electricity If the energy meter is not selected then the heat from the miscellaneous equipment will still be accounted for but the energy consumed by the miscellaneous equipment will not be accounted for Airflows tab of Create Rooms Ventilation schedules Ensure that the ventilation schedule is not an Internal loads schedule or the same as the internal load schedule used on the Internal Load tab any schedule that starts with People Lights or Misc is an internal load schedule Internal load schedules should never be used for ventilation Internal load schedules are zero percent for the heating design calculation This will cause the program to give no ventilation load for heating design This tends to lead to undersizing of the heating coils To view the schedule click Schedules on the Libraries menu and select Utilization as the Schedule type Here you should be able to view the schedule and find schedules that will give more accurate results Typically selecting a ventilation schedule for the ventilation or copying the people schedule and making heating design 100 percent midnight to midnight will give more accurate results Also if a custom schedule is being used be sure that the heating design day type for the ventilation schedule does not have hours that are less than 100 percent VAV minim
317. get to change the return air path from Plenum to Ducted To do so go to the Create Systems Selections tab and select the Advanced button Making this change ensures TRACE does not calculate a plenum temperature Not doing so could result in additional load on the system If you have a situation where some rooms on the system do have a plenum and some do not you can do one of two things you can define a one foot plenum for those rooms not having one or you can place the rooms without plenums on a separate system m Verity coil sizing and scheduling Much like with fan scheduling applying a schedule other than Available 100 can quickly lead to a high number of unmet load hours In other words if TRACE needs the coil to satisfy a load and the coil is scheduled off then the load will not be satisfied and will be carried over to the next hour Likewise undersizing coils or turning coils off can lead to unmet hours 6 106 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Modeling for LEED Step 4 Increase capacity It all other approaches fail consider increasing the system coil or plant capacity in an attempt to reduce unmet load hours Increase the appropriate coil capacities on the Create Systems Coils tab This may be an iterative process if the desired increase in capacity has a limited effect on the number of unmet hours Note Coil capacities will automatically be carried over to the
318. greatly influence the energy savings provided by these systems Note Daylight is typically defined as diffuse light and is very different from sunlight direct solar radiation The TRACE 700 Daylighting algorithm is identical to that used by the DOE 2 computer program except for the user interface It is comprised of three main stages as follows 1 A preprocessor calculates a set of daylight factors interior illuminance divided by exterior horizontal illuminance for later use in the hourly loads calculation The program automatically calculates the three dimensional coordinates of one or two reference points In a space using either the room and glass dimensions or optional aspect ratios defined by the user The algorithm then integrates over the area of each window to obtain the contribution of direct light from the window to the illuminance at the reference points and the contribution of light from sky and ground which enters the window and reflects from the walls floor and ceiling before reaching the reference points Taken into account are such factors as window size and orientation glass visible transmittance inside surface reflectance of the space sun controlled devices such as blinds and overhangs and the illuminance distribution of the sky Because this distribution depends on the position of the sun and the of 20 different solar altitude and azimuth values covering the annual range of sun positions 2 An hourly daylight
319. gy analysis NOTE The revet ond lockouts ae avaiable for the following calculation using typical weather Schedule em Fete pews 9 f f CDS PRM001 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 139 Creating schedules 10Click New Definition to define the next set of Day types in the schedule In this step the Heating design portions of the schedule will be defined to give the most conservative heating design loads 11 Click Save to add the schedule to the existing library members Note If the schedule was created while either Create Rooms or Create Systems was open Create Rooms Systems may need to be closed and reopened so that menus can refresh to include the new custom schedule 6 140 Advanced Usage and General Modeling Tips Creating schedules E Schedule Library Note The Heating design portion of the schedule is Fie View Opiom Window Help POYTa te s Ia oem amp Used to size the heating side J of the equipment i Note Enter the Start _ mh ap 11 C time End time and Ment fHeaing dengn Hearing dengn Percentage values as noted ww Sa Janusy December Jarry December Jarnimy Decors NOTE The reret and lockouts are available for the lolong Desig phase inftration vertilation reheat minimum and af system aminen schedies o gt oe pee n IMPORTANT NOTE It is strongly recommended to not use internal l
320. gy consumption for each pump On the Configuration tab add a secondary distribution pump to the cooling plant To open the Plant Controls dialog box select the cooling plantand click Plant Ctrl Choose a variable flow chilled water pump and then enter the full load energy consumption for the pump 85 kW Change the plant sizing method to block plant because the cooling capacity produced by the decoupled chillers will equal the largest simultaneous load of the coils Note The three chillers are identical As an alternative drag only one water cooled chiller to the cooling plant follow steps 2 through 6 and a then click Copy Equip twice to create the other two chillers Equpmert Category Configuration Aactcoed Ancoced cheer utay Cooling plant Cocina pare 001 Heat rejection type E5100 Cooirag tower Kari Use this entry to switch conden Equpmani categnny Waren cosied chile tessa between chillers Eaamentne 3510r Corm 2 sl Iae a Sequencing type Panini decoupied 3 4 me f T Ss fmn id 1 Crist wol chal water pumo Primary cided veat Condense wastes PND Cnel vol cnd wame pamp A cowl PP Secondary deter pure Ef wnt a Phare wizard Watercooled chile 002 EE Watencocled chide 003 Now Cig Piori 4 Either drag a pump to the New Hig Prt cooling plant ew ba click Plant Ctrl to add a secondary distribution pump To stugh equgrneri kan Da siaaa armerad
321. h Creegy rate fioo Percer efficient Hot wala pump Type None Equipment schedule Avedatie moo Ful losd p KW Demand iming h TRACE 700 User s Manual e CDS PRM001 EN Duty cycling Duty cycling helps avoid unnecessarily high peaks in electrical demand caused by synchronized equipment operating schedules This control strategy is particularly appropriate for HVAC systems with greater heating or cooling capacity than is needed to meet load conditions TP During morning warm up for example a duty cycling strategy would energize the electric heating coil in each VAV terminal at a slightly different time Preventing the coils from energizing simultaneously reduces the electrical demand peak Depending on the local rate structure demand charges can be a significant percentage of the monthly utility bill The TRACE 700 program models duty cycling only for the main cooling fan and or the main heating fan Duty cycling can also be effective for an application with several packaged air conditioning systems In this case staggering the operation of compressors or compressors and fans decreases the demand peak Figure 5 12 Comparison of heating utilization schedules 100 100 66 50 33 0 6 a m 6 p m 6 a m 6 p m 12 a m 12 Dm 12 a m 12 a m 12 p m 12 a m heating coil utilization heating coil utilization without duty cycling with duty cycling Application considerations E A building automation
322. h imi Heating wupely ar drybub 55 Sopa om ace Ells rer eral F i den po 5 Conlin SA dew paint high lent E F Coning SA d i pit low birt 55 P Dedicated Ventilation Eekaduies Dhedkoated Ventilation Locations point high limit and 55 F Codlegeal avaiable 100 Z Ded Heating cell avaisi VOECI Linvel Sarre eed at rea rece cca ier vatsa 100 for the cooling supply air dew point low limit Selection Dram Dedieated OA TerpHwmiy CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 69 Dual Path Air Handler Split Dehumidification Unit If the ventilation air is to be precooled the D create Systams Decal ae Dedicated Ventilation Cooling Coil ni schedule defines the hours of available System description Dus Pah Aa Hender z operation of the ventilation cooling coil The Coniguvion Eru Denman amp Optional ventilation cooling coil is available l l for any hour that this schedule reads Cooling Haaing Design Satpoirts c 6 Select the schedule for 1 percent or greater Cooing nepyerdyiu fS O F the coils and fan in the Habgagsyaidyhb F split dehumidification Covina supply at dew pont Ifthe ventilation air is to be preheated the unit Dedicated Ventilation Heating Coil Dedicated Vertiston Scheduler schedule defines the hours of available Costra cel i avalat 100 operation of the ventilation heating coil The ee oS optional vent
323. hamal siraga Equpmert type Cortatugsl 2 Stage w VED Tower Te None _NewEaup Sequencing hoe Paced decoupled Capacity p firr 7 Copy Equip Cooling Equipment tab Schade Srarne z Bete fade allows the user to edit the a oT l T 05 TEW ten Cenis default cooling equipment oe Le selected kwon a 7 Filoadconsumeien Paess OOOO Ea Cna vol chal water pump 5 TR water d waia pazengs 75 R wae 0 R warn 6 116 Advanced Usage and General Modeling Tips Using TRACE 700 Chiller Plant Analyzer TRACE 700 User s Manual e CDS PRMOO01 EN 11When inputs for all of the sections have been completed click Calculate and View Results then click Select All and finally click Cale Now 12View both pages of the Economics Summary report for calculation results for Alternative 1 The size of the chiller the energy rate full load efficiency of the compressor size of the pumps type of cooling tower and so on can be selected for each piece of equipment Note TRACE 700 always opens to the first chiller By clicking the Equipment tag the other chillers in the plant can be selected Note If either the Equipment Category air cooled chiller water cooled chiller and so on or Equipment Type 2 stage centrifugal high efficiency helical rotary and so on is changed then all other inputs may need to be reselected Heating Equipment tab works exactly the same as the Cooling Equipment tab Define Economics utili
324. hat consist of two or more cooling and orheating chillers piped in a decoupled variable primary parallel or series arrangement Refer to Decoupled chiller arrangement on page 3 3 Variable primary flow chiller arrangement on page 3 13 Parallel chiller arrangement on page 3 7 and Series chiller arrangement on page 3 9 for examples TRACE 700 lets you model switchover control based on the cooling or heating load the air temperature outside or a schedule that you define Related reading Chilled Water Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRC0O16 EN Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN Chilled Water Plants and Asymmetry as a Basis of Design Engineers Newsletter volume 28 number 4 Sample scenario A hybrid plant consists of two chillers and related auxiliaries piped in a parallel decoupled arrangement using a 300 ton three stage centrifugal chiller electric and a 500 ton direct fired absorption chiller natural gas The electric centrifugal chiller is Started first Operation can be switched to the direct fired absorption chiller in one of three ways m The building cooling load exceeds 300 tons m Ihe temperature outside exceeds 85 F m The on peak period is in effect 8 00 a m until 8 00 p m for this example Decoupled chiller arrangement on page
325. haust is not a significant factor If room exhaust is not entered then 250 cfm of extra return air will be calculated in the scenario above This will change the plenum temperature slightly and increase the exhaust value by 250 cfm Summary points and additional items In real life it is possible to pressurize a space by having unequal amounts of air enter and leave the soace 100 cfm more could enter the space than leaves the space This would result in positive pressurization of the space However it is not possible to continually have more airflow entering the space than leaves the space If 100 ft of extra air enters the space every minute the pressure will continue to rise until the air finds a way out When this pressure has been reached the airflows will return to steady state and the amount of air entering and leaving the space will equalize The air can leave the space as exfiltration modeled as room exhaust with no fan or as return air Conversely it is not possible to have a room where more airflow leaves the space than enters It Infiltration can be used to balance the airflows and approximate the steady state conditions for the space Remember that TRACE 700 can only model the airflows at the balanced steady state condition It cannot model the temporary imbalance in airflows that causes space pressurization In real life it is possible to exhaust air from a space without supplying an equal or greater amount of ventilation pl
326. he charges from the utility company would be as follows Customer charge 50 00 Usage charges 2 500 kWh x 0 062 kKWh 3 500 kWh x 0 032 kWh 267 m Fuel adjustment charge 6 000 kWh x 0 0189 kWh 113 40 m otal charges for consumption 50 267 113 40 430 40 api xi Fle Vew Opoa Wirrdow Help POTa Se W ceiyiadna coms ARSE TRANE Rate Structure Library Dettrption Nothemn Wisconan Utity Rate In this example the utility provides the first 10 kW for free and charges 8 45 for all remaining kW In addition the utility charges a minimum demand charge of 75 percent of the previous 11 months maximum demand Ae ra p r f a Assuming that 100 kW is the maximum demand calculated for the previous 11 months 80 kW is the peak demand in January and 60 kW is the peak demand in February the charges from the utility company would be as follows January E Minimum demand 100 kW x 75 75 kW Note Because the 80 kW consumed during January is more than the 75 kW minimum the minimum demand ratchet does not apply m Demand charges 10 kW x 0 kW 70 kW x 8 45 kW 591 50 CDS PRM001 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 153 Creating utility rates 8 Click New Definition to define the next utility in the rate structure This time Gas will be defined Define required parameters as necessary Note Cutoffs must be entered as the act
327. he airflows for room 1 balance but the airflows for room 2 do not balance the results will not be valid There is no field to input transfer air therefore it cannot be directly modeled in TRACE 700 or in any other simulation software that balances airflows at the space level The same airflow balancing rules that applied in the one room model are true in multiple room models as follows Room level balance infiltration supply air room exhaust return air System level balance ventilation infiltration room exhaust exhaust ventilation infiltration gt room exhaust There are three possible ways to model a scenario where air is transferred from one space to another 1 Ifthe air transferred from room 1 to room 2 is not used to condition the space all or a portion of the room exhaust can be entered on room 1 This will allow the program to calculate the correct amount of return air and keep the airflows balanced assuming that the airflows in each of the spaces are balanced 2 If airis transferred from one space to another and the transferred air conditions room 2 the two spaces are actually being treated as one in the building Model the two spaces as one In 6 66 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Balancing airflows TRACE 700 and make sure that the airflows balance for the combined room If the amount of room exhaust is small the assumption can be made that room ex
328. he building supply fan is scheduled to operate from 6 a m until 6 p m each day An optimal start stop strategy turns on the fan as late as possible between 6 a m and 7 a m then turns It off as early as possible between 5 p m and 6 p m An override will restore normal operation while the optimal start stop strategy is in effect if the space temperature drifts more than 3 F from the set point or if the relative humidity in the space exceeds design by more than 10 percent Note For additional information related to creating utilization schedules and reset lockouts refer to Creating schedules on page 6 137 5 Defra Month T lt prea Day type Cooling Gatin Sunday Scheck e type Utkzance Dererphon fiam topa 1 Simson ype Reduced pex Ful yea ase r dew Stat End Month ias reee Day type fCooing design esias Comments pm opima tart penod for supply lan January December Heating deagn Sahada to Sunday NOTE The reset arxi lochouts are avalabie for the bolioweng Desy phase rilsaion ventishon hoat mean axd al system saredshon tchadien System Control Strategies Optimum start and stop 5 7 3 Create a third Utilization schedule that tells the program when to search for an Optimum stop time for the fan that is between 5 p m and 6 p m on weekdays only 4 Use the Reset and lockout table to describe the conditions that determine whether the fan remains
329. he chiller plant Naming the chiller c Selecting the specific type of chiller l d Selecting the correct i Toe CoulegionewthVFDIF sequencing Parallel for this Hourly ambient wet bub ofteet exam le Equapmert type Staze Centitugal w VFD Tom G Z Thermal storage j Seamrenguee Pat qul i i xf e Inputting the chiller capacity Capacty TCO z Inputting a full load efficiency at design conditions g inputting the condenser water pump full load consumption h Eliminating the primary chilled water pump change the Primary chilled water pump type to None 7 Click Apply and then repeat 5 E leven wah VEL 1 the same process for the Enpa cag weoi Hourly ambient wet bub atit second chiller Select the Ecmomenttipe Stage Certtupal wi VFD Towe zl second chiller from the Equipment Tag list on the Cooling Equipment tab 3 16 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Variable primary flow chiller arrangement Switchover control for chiller plants alls Equipment schedules take precedence over switchover sequences For example if the second chiller in the current start sequence is scheduled off the program skips it and starts the next available chiller alls Switchover control sequences are defined for plants not equipment from the Configuration tab CDS PRMOO1 EN e TRACE 700 User s Manual Switchover control is a common control strategy in HVAC systems t
330. he desired airflow and at 75 percent of the desired airflow and TRACE 700 User s Manual e CDS PRMOO1 EN then input these values for the 100 percent and 75 percent airflow points for accurate modeling Refer to Table 4 4 for recommendations on energy recovery applications in different scenarios Table 4 4 Applications for Air to Air Energy recovery Ventilation System Energy Recovery Technology Supply air Supply air Outdoorair Source Temperature Tempering Preconditioning Dedicated Cold Not applicable Sensible or total outdoor air Neutral Sensible Sensible or total parallel or series Mixed air Modulated Sensible Sensible or total outdoor air plus constant volume parallel or series recirculated return air Cold Not applicable Sensible or total CDS PRMOO1 EN TRACE 700 User s Manual variable volume System Design Options 4 39 Sensible wheel Direct and indirect evaporative cooling Using the evaporative process to precool the supply air stream can reduce the energy consumption of mechanical cooling equipment Two methods of evaporative cooling exist direct and indirect The effectiveness of each method depends on the extent to which the dry bulb temperature of the supply air exceeds the wet bulb temperature of the supply air Figure 4 14 Examples of evaporative cooling arrangements exhaust air return air exhaust air return air exhaust air return air direct conventional conventional
331. he userinput cooling dry bulb during the cooling season or heat the outdoor air to the userinput heating Dedicated Ventilation Schedules ventilation unit will supply Cig aamenaa ary bulb during the heating season low dew point air and omer ivan Dehumidify priority or Cool Heat a un evsti ro Z dedicated ventilation unit is used to dehumidity possibly reheated in cooling mode and air ata specific dry bulb in heating mode Therefore the outdoor air to the userinput cooling dew ee ee O point not reheated during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season Dehumidify and Reheat Dehumidify and Reheat Heat a dedicated Heat will be selected ventilation unit is used to dehumidify the outdoor air to the userinput cooling dew point then reheat it to the userinput cooling dry bulb during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season 3 Select the control method for the unit Because the Create Systems Dedicated Ventilation dedicated ventilation Akanativa 1 cooling coil dehumidifies Sn cb Fe DO a rece the outdoor air to cooling Conisaraion shanty and Rohen Heat Contalmethed pirmos Sipoh atyne 3 z supply air dew point and Erami thre Ni pon Note For additional information reheats it based on the Cocina wen ard bu f related to the other Control worst case room or the C
332. heat at the local HVAC terminals Neutral temperature conditioned air which has a dry bulb temperature approximating that of the air in the space increases the cooling CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 45 Dedicated outdoorair systems 4 46 capacity required from the local HVAC terminals and requires more reheat at the dedicated outdoor air unit M Select equipment to limit indoor relative humidity to 60 65 percent Targeting a drier condition in the space will require larger equipment and consume more energy E Employ communicating controls to optimize energy use Dynamically resetting the dew point or dry bulb temperature delivered by the DOAS can minimize the energy use by the overall system Related reading m Dedicated Ventilation Systems Engineers Newsletter volume 30 number 3 E Dehumidification in HVAC Systems Applications Engineering Manual Trane literature number SYS APM004 EN m Designing Dedicated Outdoor Air Systems Application Guide Trane literature number SYS APGOOT1 EN Sample scenarios Table 4 5 Sample Scenarios Topic Scenario 1 page 46 Cool Heat Fixed Setpoints Scenario 2 page 51 Dehumidify and Reheat Heat Fixed Setpoints Scenario 3 page 56 Dehumidify Priority or Cool Heat Optimized SADP Scenario 4 page 62 Dehumidify and Reheat Heat Optimized SADB Scenario 1 A building is served by a fan coil system and a dedicated outdoorair uni
333. heating for a constant volume system with heating supply air dry bulb and airflow specified by the user 6 52 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Oversizing and undersizing Inputting the leaving cooling coil temperature will cause the same situations to occur as inputting the supply air dry bulb The relationship between the two inputs is shown below Supply Air Dry Bulb Leaving Cooling Coil Temperature Duct Heat Gain Fan Heat Gain draw thru fan configurations only CDS PRMOO1 EN TRACE 700 User s Manual Room 1 E Cooling Qs 11 000 Btu calculated by TRACE 700 based on heat gains E Heating Os 5 500 Btu calculated by TRACE 700 based on heat losses E SA 500 cfm input by user E Heating Ts 105 F input by user In this scenario the over undersizing on heating would be over undersizing 1 1 x 500 x 70 105 5 500 13 750 Btu This would indicate overheating of 13 750 Btu because the Space would need only 143 cfm at a supply air dry bulb of 105 F to properly condition the space To minimize the overheating remove the heating supply air dry bulb and or the supply airflow and allow the program to calculate the value s Scenario 2 Over undersizing on cooling for a constant volume system with cooling supply air dry bulb and airflow specified by the user Room 1 E Cooling Qs 11 000 Btu calculated by TRACE 700 based on heat gains
334. hedule J paca E g5001 Cret v l chal wata pumo E OD Cret vol ord water pump Equipment tag Walercooked chiler 001 4 e Note TRACE 700 models a 1 percent reduction in compressor energy consumption for every 1 F of reset System Control Strategies 5 25 Chilled water reset 0 64 x 0 60 0 56 chiller power kW ton 0 52 85 5 26 Condenser water reset As long as the evaporator temperature remains constant lowering the entering condenserwater temperature Increases the efficiency of a chiller That is because the colder condensing temperature reduces the pressure difference between the evaporator and the condenser easing the burden on the compressor Gains in efficiency are limited however At the system level the energy savings that accrue from 100 chiller load actively controlling condenser pressure _80 chiller load improved chiller efficiency may be offset by increased operating costs for fans and pumps Note also that chiller efficiency will Se not continue to improve with every reduction in condenser temperature Power used per cooling ton bottoms out and 80 75 70 65 60 actually begins to increase as condensing pressure falls pea ile Consequently the best way to improve chiller efficiency is by There are several ways to control condenser pressure The most versatile of these automatically accounts for changing loads It regulates the difference in refrigerant pre
335. hedule awadable fox Thermal Storage Diamar testing prisety Hoot gant reheat bo T dehurredific stion TRACE 700 User s Manual e CDS PRMOO01 EN Note If two or more chillers charge the storage tanks define the thermal storage parameters at the plant level using the Plant Controls dialog box as shown below When defining each of the ice making chillers remember to specify the capacity and energy rate when charging the tanks and to choose a schedule that makes the chiller available for storage basce he ae An coded CDS PRMOO1 EN TRACE 700 User s Manual If charged by more than one chiller add thermal storage to the plant and eomence nom Coredencer E ice making chiler 82 T Cooling tower Primary ched water puro Heating plants It Heating plat 002 Ciesception Co ng plant 009 Stingmethed Peak bared an deig seradan Heat aasit Tye Hore Hui abisa wai bulb oen Secoreiany dictibuhor pump Te Hir fc font ti i sSY EE 2 E Thama storage EY ice making chiles a1 Plant wizard Cooling tower Pray chided water pure How Cig Prora define the type Capacity and operating schedule at the plant level Cooling and Heating Plants Thermal energy storage 3 27 Cogeneration Cogeneration systems can reduce the overall energy costs for a building by generating electricity on site and capturing the waste heat produced b
336. hived and click Open thes To open an archive file 1 To open an archive file change the file type to TRACE 700 Archive files and select the appropriate TAF file 2 Opening an archive file may take a few minutes The duration depends on the complexity of the file number of rooms and systems and the number of custom library members CDS PRMOO1 EN e TRACE 700 User s Manual To simplify the process of transferring TRACE 700 files between computers an Archive Project utility has been created This utility will generate a single compressed file containing all of the project information including the custom library members used in the file Ss ee Note After the archive Note Archiving is a Som se L process is complete a good way to save files Egea EB message appears that might be retrieved os stating that the archive at a later date TEEN file filename TAF has EEr ara at been created TLE EL Ca m Filenames must be 15 characters or less No special characters dashes commas and so forth E Original Full Year 8760 hour weather files TMY TRY and so forth must be transferred separately m Chiller Plant Analyzer files must also transfer the filename os1 separately m The archive utility will clean the project file recovering unused memory It will also attempt to fix corrupted data set items m A backup of the original project file will be created A date stamp will be added to the backup
337. ht HVAC night equipment setback equipment setback starts begins starts begins without unoccupied ventilation with unoccupied ventilation Application considerations m he control system must monitor both inside and outside temperatures and or enthalpies E n humid climates avoid bringing moisture laden outdoor air into the building m Position the outdoorair intakes to avoid introducing contaminated air into the space CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 17 Unoccupied ventilation night purge Sample scenario Normal quantities of outdoor air are brought into the building for ventilation during occupancy which occurs weekdays from 7 a m until 5 p m The night purge cycle is enabled between 3 a m and 5 a m whenever the outdoorair temperature is cooler than 55 F Monday through Friday 219i x y In the Schedule library of ie ee vad POTATIS ASZ 7 iIiT EEEa coconar TRANE the Library Template Editors program Schedule type Unizo es Dercrption When Occupied 1 1 cy Create a new HEEN Utilization schedule to C Fdyou Comemerts Defines when normal vertilanon occus define when normal ventilation occurs e Sundur 21 Heater desy 2 Define the cooling design schedule to establish occupancy as 7 a m to n Udoetcn 5 p m on weekdays Then oo D define a heating design E gees schedule that is Commerts pam an rama vertistion occus 100 percent from
338. i E l Suppi a adry Eads krer kirrat fs Toong supply si dew point lt gt Tairg 5A dew part high lt F Canig SA gei piit ka ni F r Dedested Venison Schedules Deskested Ventilation Locatced Cory cod avake 00 Deck Fum ude Deck Heare cod avaisi VIECI Linwel Gbemi Optra ivi 1 dianian Aeta VEEL If the ventilation air is to be precooled the imin OO i edet Dedicated Ventilation Cooling Coil schedule defines the hours of available operation of the ventilation cooling coil The optional ventilation cooling coil is available for any hour that this W Create Systems Dedicated Yentilation kanara System descrietion Fon Co mda schedule reads 1 percent or greater Configurstion Dhuan red chest Heat f f Ua If the ventilation air is to be preheated the esing Haeata Deign bepari Dedicated Ventilation Heating Coil schedule ee defines the hours of available operation of the Heating supply ar by bul Couing ngob ar dew point Fm ventilation heating coil The optional ventilation heating coil is available for any hour that this schedule reads 1 percent or greater The Optional ventilation fan schedule defines the hours that the ventilation unit can operate _ If the Optional ventilation fan schedule reads i a l percent or greater the fan is available that hour Return Outdoor Deck conditioned outdoor air is mixed with the return air in the main unit s Plenum conditi
339. i ee ce es a EEE and Difference aici xi temperatures from the POTAZ ELIT ENA FoOmT ASE TRANE selection and also the ny EET ODS Condenser temp Deunkeng a F Design entering and Dierense 0 7 Minimum operating Deaneteng 5 F temperatures from the Mpa S S selection Tomieenca type Fan min mge e AL hot wates temp F 16Any accessories that run with the equipment None z controls solution IE pumps interlocks and so on can be selected as Miscellaneous accessories 17Click the Main tab and click Save to add the cooling equipment to the existing library members 6 148 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN Creating equipment and unloading curves Additional items 1 The Graphs tab can be used to view the Power consumed curves and the Ambient relief curves for the selected equipment 2 The DOE curves are defined using different variables than the TRACE 700 standard energy consumption and ambient relief unloading curves Additionally the capacity curve provides a way to adjust chiller capacities at off design conditions For capacity and ambient relief curves bi quadratic equations may be used as defined in the Curves library 3 Ihe Power consumed curve must be at constant condenser temperature If a curve that includes ambient modification and or relief is entered an unrealistically efficient piece of equipment will be created If the only curve available inclu
340. i sl iivesielincovelatvaecnsetavialeeestiels 6 137 Creating equipment and unloading curves 06 6 143 Vi Contents TRACE 700 User s Manual e CDS PRMO01 EN Creating utility rates clecicccsescisedsstedscrsessveascredestesecsensens 6 150 SCD OE Cilla O n S 6 150 IVE TOTO OY Talee e AEN 6 155 Stepped rate with a kWh kW flag 6 162 Adding weather locations and activating the 8760 calculation Methodology cccececee eee eees 6 167 Altering a load design file for energy analysis 6 170 Rooms tab of Create ROOMS n se 6 170 Internal Load tab of Create ROOMS 00064 6 171 Airflows tab of Create ROOMS ssec 6 172 Options tab of Create Systems eee 6 173 Fans tab of Create SYStEMS aonn a 6 173 Coils tab of Create Systems ccccecceceeeeeeeee ees 6 173 Archiving and un archiving instructions storing library members with project files cc cceeccccecceaeeeee essen eees 6 175 Printing used library Members ccccececce sees eeeeeees 6 176 COMDINNO NS Serea N 6 177 Creating a new file based on an existing file 6 179 HOW tO SOT OUTDUT auena e a a 6 180 gbXML import and export se sssssnssssesrorrerirrrrrrrsrrerrsn 6 181 Exporting goXML data from Autodesk Building DV SLC 20 Od hee asada elas toms AaS 6 182 Importing goXML data in TRACE 700 6 183 Exporting goXML data from TRACE 700 6 185 Importing goXML data in Autodesk Buildi
341. ia E Stage Centitugal 5 enwtuga Commerts CVHE CENTRIFUGAL CHILLER 170 000 TONS foe poa chile Comments Centdtuga chiller vith 2 got Cocina caapi ater o gi ir ea i gpm Eeppireard bygas Eertstugal Crai F geen pa hors cra 7 a Te Gil wal chil writer Bur Commence wae at wal ond eater pum Ambient modification eme Amb hod 3 Hore 5 Capp Demire e F Dieese fo F Datigneneing E F Minimum pasing 5 F Ta mimenns Ippe Heat erene pepee Aimar Toging ploni Ensina Flori flow cond Aow Heat rejection ype Coolers Towe 157 TO Egapen tag Cries ew coer fiver Egape category ta coed chie Thamal noraga oupas jpe FETE E gn pia bor coral Type Nene Seaencratee sire Select the newly defined chiller and add the full load ae ao aa consumption for each pump deste Si et Tari chana O Tank chagrg b hea recover TRACE 700 User s Manual e CDS PRM001 EN Purchased chilled water Purchased chilled water is water that is typically chilled in a remote location and piped to individual buildings as a source of cooling A utility company will generally create the chilled water in a central plant and charge the building owner and or occupants for the water There are several advantages to this type of operation low first cost for the building owner increased floor Space because the chillers are not located in the building possible lower environmental impacts due
342. iant floor CDS PRMOO01 EN TRACE 700 User s Manual Cienia palate ld Aa Hares J H EE Witereoedeed chii O da Chal Bean O HEE Woateroncied chis OE 68 Hening plants jar a Hande Hes J A sf Juried abai aa wey chalet uiay uo g laige parce Bader Ejazi Garie heat Pree pamp West arene eather HH Bode OF list Radart Heer G eG Doder O0E p i S FF p Aaiadid Coariga li Purigi TPs Sanderi Sone To abia equipment drag the desired equioment category in the configuration bee System Design Options Chilled beams 4 83 4 84 Underfloor air distribution An underfloor air distribution UFAD system delivers supply air via an underfloor plenum and a return air bypass arrangement around the cooling coil is implemented in order to provide sufficient dehumidification without the need for reheat In traditional systems complete mixing results in equally distributed temperatures and heat gains In contrast UFAD systems result in a temperature gradient Since the air moves vertically temperature increases as the air rises The air movement also distributes a fraction of the heat gains directly to the return air plenum Figure 4 20 Underfloor air distribution system j i caning Pern H T E optional exhaust retum fan oF gt coll bypass a cooling fan i VA v ha A floor plenum 5 pS preheat cooling coil coil ceiling plenum
343. ically Users may obtain the system fan power value from CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 97 Modeling for LEED the Equipment Energy Consumption Report if they wish to take advantage of this feature If this is done skip to step 3 1 Determine the system fan brake horsepower using Table G3 1 2 9 In this case System 5 Is a variable volume system with 45 000 cfm total supply air According to Table G3 1 2 9 Baseline Fan Motor Brake Horsepower CFMs x 0 0013 A Where A is calculated per section 6 5 3 1 1 A sum of PD x CFMp 4131 Where PD equals each applicable pressure drop adjustment from Table 6 5 3 1 1B Assume Fully ducted return and or exhaust air systems therefore per the Table PD 0 5 in w c Thus A 0 5 x 45 000 4131 5 45 Applying this to the Baseline Fan Motor Brake Horsepower formula 45 000 x 0 0013 5 45 63 95 bhp 2 Next calculate the system fan power using the formula found in section G3 1 2 9 and the system brake horsepower from step 1 System Fan Power equation for systems 3 through 8 Pan bhp x 746 Fan Motor Efficiency Where the Fan Motor Efficiency is from Table 10 8 Select the next motor size greater than the bhp from step 1 per enclosed motor at 1800 rom 63 95 x 746 0 941 50 698 W 50 7 kW 6 98 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Modeling for LEED 3 Convert
344. ication considerations m A backup source of heat is required if the heat recovered from the cooling process is not sufficient to satisfy the entire heating load E Double bundle condenser heat recovery is an equipment option that must be specified when ordering the chiller m The chiller consumes more energy per cooling ton when it operates in the heat recovery mode Related reading E Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN Sample scenario A watercooled centrifugal chiller has a nominal cooling capacity of 500 tons and is equipped with a heat recovery condenser to satisfy the comfort heating load The pumps that serve the chilled water and condenserwater loops are rated for 70 feet and 50 feet of static head respectively A gas fired boiler provides backup heat if needed using a hot water pump rated for 60 feet of static head Any excess heat is rejected from the system via the cooling tower If the entering condenser water is 85 F then the chiller consumes 0 58 kVV ton to make chilled water When no heating load exists the tower attempts to make 65 F water During the heat recovery mode the chiller can produce 400 tons of cooling at 0 70 kVWV ton CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 51 Double bundle condenser heat recovery Ils To model the cooling plant in this example 1 Pick a water cooled centrifugal chiller
345. ict hot water and purchased district steam are typically heated in a remote location and piped to individual buildings as a source of heating A utility company will generally create the hot water or steam in a central plant and charge the building owner and or occupants for it There are several advantages to this type of operation low first cost for the building owner increased floor space because boilers are not located in the building possible lower environmental impacts due to high efficiency of large boilers and so on Application consideration Purchased district hot water and purchased district steam can offer lower first costs but life cycle costs may be higher Related reading Purchased chilled water purchased district steam and purchased district hot water are all modeled similarly in TRACE 700 Refer to Purchased chilled water on page 3 37 Cooling and Heating Plants TRACE 700 User s Manual CDS PRM001 EN Purchased district steam and purchased district hot water Sample scenario In this example the building being modeled purchases hot water from a central hot water plant owned by the local utility The building owner pays only for the hot water and the electrical use of the hot water pump Note Steps are also shown for modeling purchased district steam Pijit Mivigat i 1 Masstart by clicking Create Plants 2 From the Equipment Arcokd Waterco urtey chiller g Bole Elscome fesutanc
346. if applicable Additionally define any non HVAC energy loads e g loads that consume energy but do not need to be conditioned on the Base Utility Misc Accessory tab Consider items such as exterior lighting elevators process loads etc Model domestic hot water here as well For more information on how to model domestic hot water please refer to Domestic hot water assigned to a boiler on page 3 62 After the plant information has been entered assign the various system coils to their associated plants through Assign Systems to Plants CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 83 Modeling for LEED Note ECMs are not just found at the system level m Plant controls as well as the type of plant employed may provide significant energy savings Chapter 3 Cooling and Heating Plants details various chiller plant arrangements and control methods Variable primary flow chillers thermal storage cogeneration and chiller tower optimization are only a few of the examples found in the chapter m Many types of free cooling are available in the program such as plate and frame refrigerant migration and strainercycle options m Aside from chillers TRACE also models geothermal systems Central geothermal chillers on page 3 76 and ground source heat pumps Ground source heat oump system on page 3 72 E Appendix G also requires all building end use energy consumptio
347. ighting during the sizing calculations This can be done by creating a custom utilization schedule which can be selected on the Room Parameters tab refer to step 8 of the daylighting example for the location of the daylighting utilization schedule The custom schedule would have the cooling design and heating design daytypes input as midnight to midnight O percent to turn off the daylighting controls during the design simulation The Weekday Saturday and Sunday daytypes in the custom schedule would define the hours that daylighting controls should be available to operate as Available 100 For example Weekday to Sunday could be set to 100 percent from midnight to midnight to have the daylighting controls available to reduce the lighting power during any hour of the energy analysis simulation It is recommended that a full 8760 simulation be performed if the CDS PRMOO01 EN TRACE 700 User s Manual System Control Strategies 5 41 Daylighting daylighting controls are going to be neglected during the design simulation 4 For additional information related to creating custom schedules refer to Creating schedules on page 6 137 5 For additional information related to performing a full 8760 simulation refer to Adding weather locations and activating the 8 760 calculation methodology on page 6 167 6 For additional information related to daylighting visit htto www eere energy gov or http eande bl gov Task21 LBL_1135
348. ilation heating coil is available for any hour that this schedule reads 1 percent or greater Optional Ay r dation tan Avati 1 OCC Selection Optcrns Deckeated 0A Te The Optional ventilation fan schedule defines the hours that the ventilation unit can operate If the Optional ventilation fan schedule reads 1 percent or greater the fan is available that hour Note If a custom schedule is created for the fan or coils it is recommended to use values of 0 percent for hours off and 100 percent for hours available to run to avoid confusion 7 On the Temp Humidity Abesnabree 1 System deccription Oua Pat As Harder J tab select Direct gy Ts Dehumidification Design As Tengennse Drectindrect Dehunadficaton Methods System Semasion orly er Mae Fo tps Den arean by cornaire ns con z as the Dehumidification un Sasa cen slave y a Method and specify a Main cong colaiimun alomtteleeing F Ma when trotting a chiled water cod downward Maximum room relative Mn Sarg Sarno va cl humidity of 60 A 8 a ee Mmi FfF Percentatthwathkwweed x Percent alow a medium speed SSCS S Seow detmoeoe fF Fan Meera oom relative hesredty IO Y Seecion_J_Qptions__J_DedcotedOA__ Temp Humidity Fars 4 70 System Design Options TRACE 700 User s Manual e CDS PRMO01 EN Dual Path Air Handler Split Dehumidification Unit 8 On the Fans tab input the fan type and the total static pressure for the i Create Syst
349. ild days during the spring and fall Preconditioning the outdoor air OA in this manner reduces the heating load which in turn reduces the energy consumption of the HVAC system Figure 4 2 Operating modes for coil loop energy recovery to q ON P to outdoors 75F EA outdoors 4 mw 75F lt a EA 32 5 F 85 F y to to OA an E HVAC OA my 35 F Ep HVAC system system 10 F 95 F efficiency SENe 0 s50 efficiency Ae poi 75 10 95 75 Inset A winter operation Inset B e summer operation Coil loop operation reverses during the cooling season Inset B Sensible heat is extracted from the air brought into the building and is rejected to the cooler and drier exhaust air stream This time preconditioning by the coil loop reduces the cooling load and in turn the energy consumption of the HVAC system TRACE 700 User s Manual e CDS PRMOO1 EN Coil loop for exhaust air energy recovery A coil looo also called a coil runaround loop consists of two or more Ttinned tube coils that are piped together in a closed loop A small pump circulates the working fluid usually a solution of inhibited glycol and water through the two coils An expansion tank and a means for modulating capacity either a three way mixing valve or a variable frequency drive on the pump complete this energy recovery device Figure 4 3 and Figure 4 4 on page 4 10 show the typical arrangements for sensible heat recovery in mixed air and dedicated
350. ility charges Whawmo fio 0 505 therm and a customer charge of 10 00 each month regardless of usage 6 158 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Creating utility rates 11Next the Time of day schedule must be input Jax to tell the program what FOTES lt se Os 2 IT EEn TODS armer TRANE hours are on peak and A SY _ what hours are off peak Schodde ype Uskzaten Ji m Click Schedules on the ons m d ate Faron ee Libraries menu The C Fulyeas DapiypafCocing senon S fsundy sh Library Template Editors program should open up to the schedules 12Select Time of day from the Schedule Type list 1310 create a custom schedule click New Schedule Give the schedule a name by deleting the default description and entering your own Avoid using any non alphanumeric characters in the name 14Click New Definition to m w oper oChedules are used to tell the program how the building begin defining the 2 equipment and so on operate from hour to hour schedule In this example 8a m 5 p m Monday through Friday is on peak and all other hours are off peak Select the day types as Cooling design to weekday and enter the hours and the rate types eee 13 Matty lovey pome 3 Carcel Simdation yet Reduced yoa em C Fulyew Day type Coolrg dengn fw a MEZE Nee deny __ Rete The individual defined day types also known a
351. ill cause the same situations to occur as inputting the supply air dry bulb The relationship between the two inputs is shown below Supply Air Dry Bulb Leaving Cooling Coil Temperature Duct Heat Gain Fan Heat Gain draw thru fan configurations only 6 56 Advanced Usage and General Modeling Tips This would indicate overheating of 2 750 Btu because the space would need only 167 cfm at a supply air dry bulb of 100 F to properly condition the space Any time a heating supply air dry bulb is entered for a variable volume system oversizing or undersizing of the coil should be expected To minimize the overheating remove the heating supply air dry bulb and allow the program to calculate the value Scenario 5 Over undersizing on heating for a constant volume system with cooling supply air dry bulb entered by the user or calculated by TRACE 700 Room 1 E Cooling Os 11 000 Btu calculated by TRACE 700 based on heat gains E Heating Os 8 250 Btu calculated by TRACE 700 based on heat losses E Cooling Ts 55 F Input by the user or calculated by TRACE 700 The heating supply air dry bulb will typically be calculated from the sensible heat losses and the supply cfm calculated during the cooling calculations Cooling 11 000 1 1x SAx 75 55 SA 500 cfm Heating 8 250 1 1 x 500x 70 T Heating T 85 F calculated by TRACE Room 2 E Cooling Os 11 000 Btu calculated by TRACE 700 based on
352. illuminance glare calculation is performed The illuminance contribution from each window is found by interpolating the stored daylight factors using the current hour sun position and cloud cover and then multiplying by the current CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 33 Daylighting 5 34 System Control Strategies Daylighting hour exterior horizontal illuminance obtained from the Step 1 calculation If applicable the solargain threshold is tested to determine whether the window blinds or drapes should be closed to maintain a user defined comfort level Adding the illuminance contributions from all the windows including skylights then gives the total illumination daylight effect at each reference point Stepped and continuously dimming control systems are simulated to determine the electrical lighting energy needed to make up the difference if any between the daylighting level and the required illuminance The effect of the diminished lighting level and possibly reduced solar heat gain if the internal shading device is employed is calculated and passed to the load phase Application considerations Daylighting does not necessarily mean an increase in the amount of fenestration on a building Proper placement and configuration for the fenestration is as important to a properly designed daylighting system as the amount of fenestration When designing a building with daylighting be aware of the p
353. iltration room exhaust 200 50 350 100 cfm The airflows do not balance therefore the results will not be valid In a one room building it is not possible to continually exhaust 100 cfm more of air than is brought into the building If a building was set up to operate in this manner eventually infiltration would increase or room exhaust would decrease so that the airflows would balance TRACE 700 will automatically decrease the room exhaust to balance the airflows For airflows to balance the following equation must be followed ventilation infiltration gt room exhaust Refer to Summary Point 1 on page 67 for a more detailed explanation of this scenario CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 63 Balancing airflows When more than one room is involved modeling becomes more complicated Iwo more scenarios will be used to illustrate how airflows are calculated Figure 6 8 Multiple room airflow balancing Exhaust Air Supply Air ACU Ventilation Transferred Room Air Exhaust Room aici Room 1 Room 2 Infiltration Infiltration Scenario 5 Two rooms with balanced airflows and no transferred air Room 1 E Ventilation 200 cfm AIRFLOWS m Supply Air 1000 cfm Cooling Went 700 E Infiltration 0 cfm a T Min Stop Rh m Room Exhaust 0 cfm 1 000 E Iransferred Air 0 cfm Room 2 E Ventilation 300 cfm AIRFLOWS m Supply Air 1000 cfm Cooling
354. imulation as the sum of the hourly room requirements for outdoor air This control method does not satisfy the ventilation requirement for multiple space systems that is defined in ASHRAE Standard 62 2001 5 16 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Ventilation reset for VAV systems Unoccupied ventilation night purge Unoccupied ventilation can serve as an effective tool to improve indoorair quality by flushing many indoor contaminants from the building This practice introduces large quantities of outdoor air to purge stale air from the building without increasing the cooling load In climates with cool nighttime temperatures this control strategy can also reduce utility costs by taking advantage of the thermal capacity of the building When the nighttime temperature outside reaches a predefined value the control system activates the supply fan and opens the outdoorair damper to Introduce outdoor air directly into the building The fans remain on until the space temperature falls to a specified level In effect the cool air brought into the building at night reduces or eliminates the morning pull down load that often develops in a building during the cooling season Figure 5 6 Effect of unoccupied ventilation on space temperature scheduled occupancy scheduled occupancy space temperature space temperature 12 a m 6 a m 12 p m 6 p m 12 a m 12 a m 6am 12 p m 6 p m 12 a m HVAC nig
355. in the library Sieds joni J 3 30 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Cogeneration Direct fired absorption cooling As the name implies a direct fired absorption chiller relies on natural gas or other fuels to drive an absorption refrigeration cycle The highly efficient performance of the chiller which typically results in a Coefficient of Performance that exceeds 1 0 including burner losses enables it to compete favorably with electric chillers in many regions where electricity rates are high What sets direct fired absorption chillers apart from other machines is their ability to serve either a cooling load or a heating load This flexibility can be particularly appealing for applications that need chilled water for comfort cooling during the summer and hot water for comfort heating during the winter In these applications the direct fired absorption chiller can replace the traditional chillerand boiler combination while occupying significantly less floor space Figure 3 7 Direct fired absorption chiller as a chiller heater changeover valve refrigerant vapor hot water evaporator absorber high temperature generator Application considerations m Manufacturers of direct fired absorption chillers often provide both standard and high efficiency models in sizes that commonly range from 100 to 1 100 nominal tons m Consider using a direct fired absorption chiller a
356. included with TRACE do not meet this requirement and users need to import a full year weather file in order to comply Refer to Adding weather locations and activating the 8760 calculation methodology on page 6 167 for details on how to conduct a full year analysis in TRACE The recommended file formats include TMY TMY2 TMY8 or IWC Full year weather files using these formats can be found at www DOE2 com under the Weather Utilities section Additionally full year weather files can be purchased through ASHRAE There are many sources for weather however in order for TRACE to use the Tile it must be in one of the following formats CEC CTZ CWC IWC TMY TM2 TM3 TRY WTR or WY 2 Calculate and calibrate Prior to modeling the baseline building the proposed building should be calculated and reviewed for accuracy Due to the vast number of inputs reviewing output data to ensure the proposed building is modeled accurately is critical Output data should be compared against mechanical schedules if available or other design documents detailing expected operation Following are guidelines for troubleshooting potential mismatches between output reports and design documents This list is not all encompassing and is offered only as a basic outline Design values mismatch m Verity envelope loads match design criteria m Verify internal loads match design criteria e g densities schedules m Verity thermostat setpoints schedules m
357. ing demand for a building but does not handle the heating load a gas fired boiler provides hot water for this purpose Abematrve 1 Cooling plant Cockers pisne 001 Heat rajacton type fe qstos Coukry tower Equipmert tog Crier 1 7 Equpmert category Watercooled cher v Thana shores Equpmert type lo Drect Fred Ahsen 1 ER J Type None EqQo001 Crest vol chal waster pumo E Pall Crt vol rel wale peer Plant description Cooling plant O07 Eqpapenerd bag Chia 1 Pump il bead enengy Y jm p Equipmert tag f odes 1 Equpmert cotegory oder Mae chided wahi piia jo F Equpmert type Gas Fred Hot Water Boder 5 Load shedding econcmene He z Capacity Mba Y Eneegy rate fea 3 Percent efficiert bd Equoment schedule Awadable 1000s Hol water pump Cherrennel kming priority TRACE 700 User s Manual e CDS PRM001 EN ing Low flow chilled water systems TP The standard rating conditions established by ARI 550 590 1998 set flow rates of 2 4 gom ton and 3 0 gom ton for the evaporator The condenserwater and condenser respectively This evaporator flow rate flow rate for absorption corresponds to a 10 F temperature difference AT The chillers is slightly higher 3 6 gpm ton for single effect machines and 4 0 gom ton and 4 50 gpm ton respectively for double effect steam hot water and direct fired machines condenser flow rate yields a 9 1 F to 10 F AT depending on compres
358. ing schedule should be used to cycle the fan not the fan schedule Energy Only Note The fan schedule overrides the fan cycling schedule Refer to Frequently asked questions on page 6 20 for additional information CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 13 Common modeling mistakes Coils tab of Create Systems Pani FarrPoweed VAV X ol Denpi Cocking Capacity Cooking Uriy Design ME Avaldis 100 of Dengi Capacity Avebatie 1003 of Dewgn Capacity Lights Homes of Dewgn Capacity fovedabie 100 of Dengi Capacity Custom Schedule apay fovedatie 1003 Temoy Hurnidty m A capacity 52 MBh for the auxiliary cooling coil has been input Only the induction system types 2 pipe and 4 pipe Induction have an auxiliary cooling coil by default it is the secondary induction coil located in each room However it is possible to add an auxiliary coil to any of the other system types by specifying a capacity value units typically as 100 percent of Design Capacity This auxiliary coil is sized according to the skin envelope load In addition this auxiliary cooling coil can only operate during the summer period months as defined on the Load Parameters screen Activating this coil can lead to erroneous load calculations and energy analysis Load Design and Energy m Acapacity 100 percent of design capacity for the auxiliary heating coil has been input Only the 2 pipe
359. ing the Description list will allow the user to select any wa can be found below the comments section of the schedule The Definitions tell the program what values to use during the different parts of the simulation Cooling Design is used in the cooling aer design and in reduced year analysis for the peak kW portions of the calculations Heating Design is used in the heating design yg Portion of the calculations Weekday Saturday and Sunday are used in the energy analysis kWh portion of the calculations Pande to be viewed The individual Definitions in the schedule w Library Template Editors alBi x Fie View Options Window Help COTE te Ree Tbs COMT ASE TRANE Stat End Morth Plaruay December Dap type Contry degr Senda 6 138 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Creating schedules 7 Begin by selecting the Day types that you would like to define In this case the Cooling design portion of the schedule will be defined to give the most conservative cooling design loads and airflows Note For a less conservative cooling design calculation the cooling design day type can be scheduled identically to the weekday day type w Library Template Editors ald x Fle View Options Windew Help POTALA eiT Iih comana TRANE ae a ce Note Enter the Start time End time and ox d i res d Percentage values 7 Cmte Coca sey
360. ing the heating season the airdistribution system includes a steam humidifier that is fed by a gas fired boiler vAV System ste Sts Fare Powered vav To rename a system type Set the new description here or Nl el on Begin by defining the air distribution system Bypars VAV wath Local Heat Crangeover Bypars VAV wath Reheat Doutie Duct vav Parallel F an Poweered VAV Hig Cod on Moang Box Ouilet Passel F anr Povcered VAV Paralel F an Poreered VAV 1 Choose Variable Volume as the system category and Series Fan Powered VAV as the system type System description AV System 1 Soins Fan Powered VAV gt 2 Add a humidification coil to Deng Ae Tempehae r Daectfrdrect Dehuradticahen Methods Sysiem Serudston ordy e Cooling supp Maf F Ie hee o OY the system by specifying un 7 Sa m the minimum room ERE wal 4 relative humidity For this niaii lt onde Dei ps ree example use the minimum Variable Fan Speed for capacity control System Siendation oriy so dus F Number of lan speeds p on room relative humidity patric n Pacer siden stoned a recommended by ASHRAE Percent stow at median speed Supply dattonpeahec 0 F EE which is 30 percent TETERE M aru The humidification coil will e 2 activate whenever the relative humidity falls below this value 5 10 System Control Strategies TRACE 700 User s Manual e CDS PRMO01 EN Humidification llay Next des
361. ion Ge Deck Sytem vemilshon Meg Sus Riem 04 Aegi MS Seok ASHRAE Sid EZ 2MVA007 People Avenger yes No wining Tha Bedy mative in cad ane cone SS PIPL SUGGS Mace Vert Z Plats Avent x Dampier of the piia Changer gt rence wakes cam tithes as sech hras Population Diveriy non DE Foams ony TX thee ipile operated Fieri make rue POU ae e of re tobe aao OO2 based DOY None P Fromo n i Sre Se tems pou make such a charges Selection Opre Descwed a IempHumsy Ears Cole Schematic 4 68 System Design Options TRACE 700 User s Manual e CDS PRM001 EN Dual Path Air Handler Split Dehumidification Unit 3 On the Dedicated OA W Create Systems Dedicated Ventilation E la x 7 Akamara a oo Dehumidification Unit Cancel 3 Aoniiggur sition Spe Dehuridizaion Ll ru imdnal meth CELI Cockrg Hawting Deign Depart oingtiesing Separ Liai Cooling rupp ar dep bulb F Suppi air dry bulb high imi F Heating rupely ar drybub F Guppy am chy bulbs kerkt F Couing agp a depan OOO E eg SA de peit hihi F Coning SA d piirit kos beret F Dedicated Wendyn Schedules Conny cad avuke 100 Heating cod avaisi 10005 Ta s Eonian VICE pelecton Drar Checieabeedl 1A TempyHuredty Fare Cok Sebena Split Dehumidification Unit a dual path air handler brings outdoor air through a dedicated coil to cool the outdoor air to the userinput cooling dew point not reheated during the cooling s
362. ion Note When using the ASHRAE Standard 90 1 2007 calculation method define pressure drop adjustments on the Fans tab of Create Systems lf credit is taken for more than one pressure drop adjustment total the number of pressure drop adjustments and enter that value 3 To identify the baseline alternative access the Calculate and View Results screen Select the baseline alternative using the drop down menu for the Performance rating method x Simulain hour Peia ps L LEZ Ca Caira code i Laid fir a Dy En Dra Vint month Jafar Gm Lan rerh a i E Unk airida zal apritei Bp Steam B naamioi T Ho magier E E P 1 srie ran oueeretes ali Alp Tp FT F Woman Voima fstas JE bes kea isis o Once the baseline system fan energy has been calculated TRACE will apply this energy to the primary fan if it is the only qualifying fan listed on the system In the case when more than one fan has been entered for the system e g exhaust fan a portion of the system fan energy will be applied to each qualifying fan The amount each fan receives is based on the Full Load Energy Rate defined by the user for each baseline fan The fan power ratio for the baseline must be the same as the proposed Note ASHRAE 90 1 2007 considers most but not all fans in the baseline system fan energy calculation Consult Appendix G to determine which fans are considered in the calculation CDS PRM001 EN
363. ions Wile pa sceboard Heating Stage 1 Batons Energy Menyra Transen Stage 2 Aimiodur Enesgy Pecowerpe T tenable Type Teta aneegy wheel IA peacondtor Twe Hee peia Eahania deck Foce aha Gwhside deck Oud Saat ae Scheeckulin avai 0 Schedule m For the energy recovery transfer devices on the Options tab of Create Systems the airstreams that will be used are not selected correctly If the proper airstreams are not selected the energy recovery transfer device will not function correctly or may not function at all Refer to Coil loop for exhaust air energy recovery on page 4 8 lotal energy enthalpy wheel on page 4 15 Fixed plate heat exchanger on page 4 21 Heat pipe on page 4 27 or Sensible wheel on page 4 34 for instructions on properly modeling energy recovery transfer devices Load Design and Energy CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 11 Common modeling mistakes Temp Humidity tab of Create Systems Decctlreirect Dehumreiteoton Methods System Senmisin ordy Max 75 F Type g z Mn 5 F Maram 100m relative humedty Mef F Mn Max 55 t Mn for F Supply duct tempersiure fo 1 ditearerce Rehan temperature dilamet Selection m Ihe input cooling supply air temperature 75 F is too high The cooling supply air temperature must be lower than the entered room set point for cooling in Create Rooms This
364. ior equipment type a centrifugal chiller for this example 2 Specify the full load T consumption for each TEI C EGET Chat vel hl wate pomp A ets feat Ega0ig net wal ond wate pump s pump 3 Click Controls and choose strainer cycle from the list of free cooling types If strainercycle free cooling occurs at the plant level If load then mechanical Mm e siwsmssi o F f Load shedding economize Ho el the cooling plant includes cooling is used instead SE fe multiple chillers repeat this Energy source Faaal ciinii haa Haa rejoin dauan z step for each chiller neama SC Equipment pchechube rwslabie 10I r Hat gare reheat ia T 7 dehur diic stion CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 49 Strainercycle free cooling Double bundle condenser heat recovery The double bundle method of condenser heat recovery can reduce the amount of energy consumed for heating in chilled water applications It adds a second heat recovery condenser to collect heat that normally would be rejected to the cooling tower by the cooling condenser The collected heat is then used to pre heat water for domestic use comfort heating or a process application Figure 3 12 illustrates a typical chilled water plant equipped to satisfy concurrent cooling and heating loads When a heating load exists water flow through the cooling condenser is adjusted so that the chill
365. ir in the upper portion Is much warmer In addition to supplying air at low velocities displacement ventilation systems must also supply conditioned air at temperatures typically between 65 F and 68 F to avoid drafts and cold feet Displacement ventilation systems can be paired with radiant ceiling or chilled beam systems that handle some of the sensible cooling loads of the space Application considerations m When 100 percent outdoor air is used good air quality conditions can be achieved because the contaminants are continually exhausted from the space m Ihe use of warmer supply air allows extended use of economizers especially in drier climates In addition climates with low humidity may also operate with chilled water at higher temperatures which improves chiller efficiency E In humid climates the supply air typically must be dehumidified before being reheated or mixed with return air to reach the desired warmer supply temperatures typically 65 F or greater 4 88 System Design Options TRACE 700 User s Manual e CDS PRMO01 EN Displacement ventilation To model a displacement ventilation system begin by specifying the ventilation for each room 1 On the Airflows tab of Create Rooms specify the ventilation for each room Note TRACE defaults to 100 Outdoor Air for the Displacement Ventilation w Chilled Ceilings Displacement Ventilation w Passive Chilled Beams and Displacement Ventilation with Room Ind
366. is installed you can use your computer to access the TRACE 700 home page on the Trane Web site TRACE 700 User s Manual e CDS PRMOO1 EN The TRACE 700 home page provides links to downloads support and on site training You can also subscribe to a news service to ensure that you are automatically notified whenever new information is available To visit the Trane Web site 1 Go to the Trane home page at www trane com and click Commercial and Industrial 2 Click Products Click Software on the list to open the C D S Software page 4 Under Analysis Tools click TRACE 700 for information regarding the software If you have a customer number click Knowledge Base Center to view common questions and answers regarding Trane software products Alternatively either access the Internet and go to www tranecds com or from the TRACE 700 application click Help gt Trane on the Web TRACE 700 terminology Like most software the TRACE 700 program has a unique vocabulary Many of the terms will already be familiar It is however important that you understand the fundamentals described here Rooms and zones TRACE 700 defines a room as the smallest space for which it can calculate a heating or cooling load The space may be a large open plan office that occupies the entire side of a building or it may be a conference room separated from adjacent spaces by interior dividers Each room is bounded by surfaces that cont
367. istakes 6 4 plenum height is subtracted from the floorto floor height to determine the height of the space that is conditioned Not correcting this inout can lead to underestimation of airflows and loads For additional information refer to Figure 6 1 on page 6 30 Load Design and Energy The input values for the design cooling and heating dry bulb are not the same as the worst case temperatures in the selected Thermostat schedules For example the design conditions for the selected room are input as 4 F cooling and 70 F heating The cooling and heating systems will be sized based on these values If the Thermostat schedule shows a minimum cooling setpoint of 73 F in the summer the cooling coil will probably be undersized Similarly if the heating Thermostat schedule shows a maximum space setpoint of 72 F in the winter the heating coil will probably be undersized Load Design and Energy The default values for the design thermostat setpoints are being used 75 F for cooling 68 F for heating and 50 percent RH For accurate results the actual space setpoints should be entered Load Design and Energy The default values for the thermostat driftpoints 90 F and 55 F respectively are being used This means that whenever there are 5 percent or less of the people in the space determined from the people schedule the room will be allowed to drift up to 90 F or down to 55 F before the coils turn back on If the building control
368. it the description of the individual room s or edit the template to automatically update all affected rooms Libraries contain the common design parameters for construction materials equioment base utilities weather and scheduling all of which TRACE 700 uses to calculate building and equipment loads Much of the information in the libraries reflects the design parameters published in the ASHRAE Handbook Fundamentals and similar industry references Refer to online Help for more information about these and other TRACE 700 terms CDS PRMOO01 EN e TRACE 700 User s Manual A Brief Introduction 1 7 About TRACE 700 1 8 A Brief Introduction TRACE 700 User s Manual e CDS PRMOO01 EN About TRACE 700 Program Overview alls A All TRACE 700 simulations of systems and equipment are based on data from the manufacturer TRACE 700 comprises four distinct calculation phases that together provide a comprehensive energy and economic analysis load design system air distribution simulation plant airconditioning equipment simulation economic analysis Calculations in the load design phase provide sufficient detail about the heating and cooling loads to evaluate the effect of building orientation size shape and mass based on hourly climatic data and the resulting heat transfer characteristics of air and moisture After the load design phase is complete subsequent calculations simulate the operation of the buildi
369. itors Fie View Opiom Window Help lt m A The Energy Rate should only include the d POY ate Boe i y EE E Cooting Equipment Main Conslart v ime pump Constart v ime pump Capacity j 4 Input the Energy Rate required and the Cooling Capacity optional from a the selection The Energy Rate is 107 72 kW 128 76 tons 0 837 kW ton These values can also be input or overridden on the POTAZ TS AS lyse Tes AgseE e Cooling Equipment tab en at A a ipata Pump sizes are input on the of the Create Plants panes Cooling Equipment tab of section ss aa the Create Plants section 5 Select the Type of Pumps to be associated with the equipment If the equipment is not associated with a pump then select None as the pump type Sere T mE a ars The Curves library will 6 Click Curves to input the Ss custom unloading curve from the selection software Cooling Equipment library CETA p j CDS PRM001 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips Creating equipment and unloading curves 6 145 7 The Curve Type defines iaizi Fie View Options Window Help the type of curve being POTaste eerl 79s CONST ADS TRANE created Select a Cooling equipment power consumed curve and click New SAE 7 Cooling equpmert power consumed gt 8 Name the new curve by deleting the default Description and entering a
370. ject Abansieve Abemstive 1 X i Descipies Dets Templates Inteerusl load Aaram Densp i inienn Schedule Ecuina Cire engri Laera 50 ituh Lghiry Note The internal load schedules tes _ Recrted Marieen ratvenes 416 typically should not use the schedule Hestgan 0 wah Sebel Coo Available 100 or any schedule M where the heating design day type is Ene 0 e ai ca greater than zero This will cause mD hoe a TRACE 700 to take credit for internal intemal Load TANANA loads during the heating design ense ere Calculation For additional details on tsan meas SChedules refer to Creating schedules on page 6 137 Lo Fanny People Tee Genes Otea spee o Density M3 iamen Schedule Pectie Low Fine Otice ome Senable 50 Otwh E Laau a0 ah 3 Lagha Tee Recersediucencent vented ishan 20 badio esee Haat gan 15 Wah Schedis Latr Lowrise tiee Miscndarnon kvak Tee 89 indOticeEquenet O Erg 05 waan Schedule Mie Lior olhce Eng Emeen x TRACE 700 User s Manual e CDS PRM001 EN 4 With the general characteristics for the xl Note In almost all cases the i ar berate Atersi ooe a mrornal loads Demsigion Dice vea Auxiliary supply and VAV erinea select the Manap Ausdiany uath minimum schedule should be Airflow tab Here the o DIESE JIEN iet ariherdefault values Al Hesna Tobecacuated m Heating
371. jection squipmari z Feact Fei ta plant E satisfy the entire cooling load l Eqiprmen ochedube Ayesdable 10 remane beating peip Hist gare rahest oe ns Cooling and Heating Plants Plate and frame free cooling 3 45 Refrigerant migration free cooling As the name implies refrigerant migration free cooling is based on the principle that refrigerant migrates to the coldest point in a refrigeration circuit Under favorable conditions this energy saving option for centrifugal chillers can provide up to 40 percent of the design cooling capacity of the chiller When condenser water returning from the cooling tower Is colder than the water in the chilled water loop as depicted In Figure 3 10 the refrigerant pressure in the condenser is less than that in the evaporator This difference in pressure drives refrigerant vapor from the evaporator to the condenser where it liquefies With the help of gravity the liquid refrigerant flows back to the evaporator The non mechanical refrigeration cycle is sustained providing free cooling as long as the differential refrigerant pressure Is sufficient to drive vapor from the evaporator to the condenser Figure 3 10 Refrigerant migration free cooling from A compressor Ko shutoff valve vapor migration evaporator Application considerations m Mechanical cooling and refrigerant migration free cooling cannot occur simultaneously This type of free cooling c
372. k Enter Project Information input the project information and click OK Note Avoid using punctuation and special characters in the Project Information section Also this information will appear on the Title Page report and the Economics Summary report TRADE New File Wirand Step Perimeter depth should typically not exceed 25 feet or the envelope losses could be negated by the internal loads Also you may want to note the number associated with each of the spaces in the wi building as TRACE 700 will name Legh xo k Pescert hone the rooms based on these E i numbers In this example x TRACE 700 will create five rooms Ten a j 5 doi using the Wing numper the oom number and the Direction Se WeRIN W1 R2E W1 R3S W1 R4W and W1 R5lnt Fitofiheaght 17 h 5 Em we TRACE 700 C CD5 TRACE7O0 Projects TRACEO14 tre laj j Fie Edt Actors View Options Liras Tempides Ahenalves Setup Window Help Seo gt Rercketevne STAR TRANE Pract Varnenindutnes Hessoustes Locahen Davergort lA Bukingowner Varneningntes SS favas o CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 111 Quick building inputs via the New File Wizard 7 Click Select Weather Information click the appropriate region of the country click the nearest weather location and click OK Note If the desired weather location does not exist select a weather location
373. kWh x 0 06 kWh 9 000 10 000 1 000 kWh x 0 05 kWh 15 000 25 000 10 000 kWh x 0 04 kWh 1 000 kWh x 0 055 kWh 24 000 50 000 25 000 1 000 kWh x 0 035 kWh 200 customer charge 2 205 February The cutoffs are determined by the kWh kW floating cutoffs m 700 kWh kW x 200 kW 20 000 kWh m 270 100 110 KWA KW x 200 kW 42 000 kWh For the month of January this translates to the following rate structure m 0 7 000 kWh 0 06 kWh m 7 001 10 000 kWh 0 05 kWh CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 163 Creating utility rates 10 001 20 000 kWh 0 04 kWh 20 001 21 000 kWh 0 055 kWh 21 001 42 000 kWh 0 035 kWh 42 001 infinity kWh 0 03 kKWh Actual consumption 35 000 kWh from table above Consumption charges 1 000 kWh x 0 06 kWh 9 000 10 000 1 000 kWh x 0 05 kWh 10 000 20 000 10 000 kWh x 0 04 kWh 1 000 21 000 20 000 kWh x 0 055 kWh 14 000 35 000 21 000 kWh x 0 035 kWh 200 customer charge 1 655 Note Rate structures are used to tell the program what the utility company s charge for electricity water gas and so on The individual defined rates also known as definitions can be found below the comments section of the rate structure The definitions tell the program what values to use during the different parts of the economic calculations TRACE 700 will not calculate costs for a utility electricity water and
374. l Yes THY Cancel Comrenarts PA Start Phe V Opio Widow hwo FOV E a AE a a E E n a E G TRANE Regen Subiegen Location United States roth Corra fakon Obes Save afs Clove Laude 51 impot Fe CACOSATRACE PON PsojectsiSTLOUIS TMY Lengnude 63 Eegen Subregion Location VERY IMPORTANT The values input for Summer OADB F OAWB and Winter OADB would typically be obtained from the ASHRAE Handbook of Fundamentals For example 1 cooling design weather and 99 heating design weather would be used iw Copy nawa we TRALEO 700 CACOS TRACE 700 Projecis TRACEOO2 trr Fle Edt Anora View pioa Libearies Templates Alernatives Setup Jao oR OF EAKkA Bis Project Navigator Obamas 1 z B Weather EJ a ee I O T 5 Select weather Infomation BE owe race If the design conditions are not changed before the import the weather profile generated for the design calculations will be overly conservative 6 168 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Adding weather locations and activating the 8760 calculation methodology so TRAC T00 0 05 TRACE TOD Projects TRACEOO2 irt Fie Eda Acton Wer Opra Libraries Temale Miri Gel V Salat Weather Informatie Trara Teele Trara Boomi Cresta Diybghing Defirdii Create Grii Arig bsama by Dyami Ariy Gyi bo Ban Cres
375. l rooms and zones assigned to that system For system level units each airside system would represent an air handler or RTU and the zoning would work as shown above After calculations have been completed the user would want to look at the System Component Selection report for all coil and fan sizing information Alternately the user could refer to the Zone or Room Checksums for VAV box sizing information and the System Checksums for supply fan preheat coil and main cooling coil sizing information Zone level coils Figure 6 4 Single zone or VTCV only g Single Zone Rooftop a Single Zone Rooftop g Single Zone Rooftop gi Single Zone Rooftop 1 amp East one E East Room L amp 2 Room Zone L as East Zone L g East Room E west Room E East Room Le E ast Room amp West one fq west Room gi Single Zone Rooftop 2 L A west Room Lg West Zone E E West Room Rooftop 1 Rooftop 2 1 Rooftop Rooftop 1 Rooftop 2 East Room East Room East Room West Room West Room West Room In TRACE 700 single zone SZ and variable temperature constant volume VTCV units represent zone level pieces of equipment These two system types SZ and VTCV are commonly used to model constant volume rooftops and by default are the only zone level systems available by default For zone level systems each zone represents a separate RIU and the zoning would work as shown in Figure 6 4 6 48 Advanced Usage and General Modeling Tips TR
376. lalion Locations esing Heating Daiga Sepan Coding mock srdybub 70 F Going rupp a dew pont F m Dedicated Ventiytion Eehaduies Coige ave Dack Feum da eek o o Haare cod Aunis n Lial Syren a Dipper Emitte IEEE f EE WE verdiation If the ventilation air is to be precooled the Dedicated Ventilation Cooling Coil W Create Systems Dedicated Ventilation ae schedule defines the hours of available System description Fan Cole end DOA operation of the ventilation cooling coil The Conigxsinn Cams Optional Ventilation cooling coil is available re for any hour that this schedule reads esip Heating Caan Depant me l 1 percent or greater Cooling eph ar dybt 70 F Hiara rupp a dy bel ca F Coinga side OOOO F Ef the ventilation air is to be preheated the Dedicated Ventilation Heating Coil Dedicated Vertitstion Schedkies schedule defines the hours of available Cooling eal raen re operation of the ventilation heating coil The tenia j optional ventilation heating coil is available for any hour that this schedule reads 1 percent or greater Chediesabed DA Is The Optional ventilation fan schedule defines the hours that the ventilation unit can operate If the Optional ventilation fan schedule reads 1 percent or greater the fan is available that hour into ne Eoia IEEE Selection pirt Note If a custom schedule is created for the fan or coils it is
377. lant and A glass comparison CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 131 Creating alternatives Sample scenario 1 In this first scenario multiple AHUs in Alternative 1 and a central AHU in Alternative 2 the alternatives will only require a change to the Airside Systems section In this case the second alternative will be copied from Alternative 1 The illustrations that follow demonstrate how to create a new alternative by copying an existing alternative Step 1 naming the new alternative Step 2 and editing the appropriate sections of the new To copy Alternative 1 1 Select Copy Alternative from the Alternatives Setup list A second alternative is created that uses the data from Alternative 1 Note The Alternatives Setup menu can also be displayed by right clicking the gray bar labeled Alternative 1 2 To name the new alternative double click the project information for Alternative 2 to display the Project Information window and edit the Description field Note The Project Information window can also be displayed by clicking Alternative 2 and then clicking Enter Project Information 6 132 Creating alternatives Advanced Usage and General Modeling Tips alternative Steps 3 and 4 re TRACES TOD for ecclusive use by CACOS TRACED Projects File Edi Aea View Opiera Litrariet Ternplitiet Alberalives fahun Winkie Sehoe elec gee
378. lb and humidity with this smaller airflow Also be sure to verify that the higher airflow will not cause moisture carryover for the selected cooling coil 5 Trane Official Product Selection Software TOPSS can be ordered by contacting C D S at www tranecds com or from the TRACE 700 application click Help gt Trane on the Web Note Because the coil airflow is generally constant in a constant volume system the airflow at the time of coil and space peak will be the same However this is not true for mixing systems in which the fan is constant volume but the cold deck mixes with a bypass or hot deck to achieve the final supply temperature to the spaces For example the cooling coil in a multizone system need only be sized for the maximum block building load and the associated block coil airflow while its fan must be sized to handle the peak airflows to all the spaces At the time of the building block cooling coil peak the cooling coil on the cold deck sees only this block coil airflow while the remaining supply is bypassed through the hot deck Note If a different cooling supply air dry bulb temperature is required based on the cooling coil selection revised supply air temperatures should be input in TRACE 700 on the Temperatures tab of Create Systems The simulation should then be rerun so that the fan and terminal boxes are properly sized CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 79 Sel
379. lding Design and Construction version 3 specifically Energy and Atmosphere Prerequisite 2 EAp2 requirements and Energy and Atmosphere Credit 1 EAc1 requirements ASHRAE Standard 90 1 2007 specifically sections 5 4 6 4 74 8 4 9 4 10 4 and Table G3 1 ASHRAE Standard 90 71 2007 User s Manual TRACE 700 User s Manual e CDS PRMOO1 EN wal Proposed building Start a LEED model with the proposed design As a general rule MS ooo DION GS a the building should be modeled per its design specifications overview of the steps required to model the proposed building For more detailed Comply with the mandatory requirements of ASHRAE 90 1 2007 information on how to perform specific tasks in Hl Meet the requirements of LEED EAp2 and EAc1 TRACE refer to the applicable section in this When complete the proposed building must Match the design parameters manual To learn TRACE The following is a recommended workflow for building the basics refer to the proposed building in TRACE Many methods exist yet differ Getting Started guide depending on company policies and practices Please treat this as one possible path to follow Collect data To save time collect and organize the data for the proposed building prior to beginning the analysis While the following Is not an extensive list information you will need includes m Envelope construction information e g wall constructions roof constructions window types
380. le click New Sched 4 In the Description field delete the default schedule name and enter a name of your choice Avoid using any punctuation in the name 5 For the Simulation type select Reduced year if you are using the default calculation methodology or if all of your weekdays are utilized the same Select Full year if Mon Fri have different utilizations you are using the 8760 calendar and using imported 8760 weather Note Reduced year schedules can be used in 8760 simulations Full year schedules should not be used in reduced year simulations Please call C D S Support at 608 787 3926 with questions about 8760 analysis Full year vs Reduced year analysis 6 Click New Definition to start defining the schedule TRACE T00 for I use by iajxi Fie Adora Ubrares Help gt Bre Union Doe sum TRANE Contructon Types Laverent Gus Tyypit Intern werd Airflow Loads Utilization schedules are typically used to tell the program how the lights people miscellaneous equipment Rite Srucharet E des Uniosding Curves Werther x Libxary Template Editors ventilation and so forth are alBJ 2 POYTa2 te s 1 ig E4 utilized in the building g E Schedule Library E alii x 2 Cear omen J p Schade Dron aoa Stat Ered ai I l men poy frente s yeu Crave Ow ieefinra mer Sli E onsena Es Click
381. le you will see the only difference is the heating design value is set to 100 percent for ventilation CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 105 Modeling for LEED Similarly using a ventilation schedule of Available 100 may not always be appropriate Depending on code requirements introducing ventilation only during occupied periods can provide substantial energy savings Utilizing the Available 100 schedule brings ventilation air into the space 24 7 unless ASHRAE Standard 62 1 with ventilation reset control is enabled m Check VAV airflow Typically this occurs with VAV systems and manifests as unmet heating hours Since heating airflow is limited by the minimum stop of a VAV box sufficient airflow may not reach the space to satisfy the load You can detect this by reviewing the Room Checksums report If the heating supply temperature appears unusually high consider increasing the VAV minimum for the Space Likewise if the space does not receive the required ventilation during heating due to the minimum stop select Actions gt Change Load Parameters from the menu bar On the Change Load Parameters screen check the Force VAV minimum always gt nominal ventilation during design box This will adjust the VAV minimum automatically to ensure the Space receives the defined amount of ventilation m Correctly define the return air path Those modeling spaces without plenums often for
382. le frequency drive Step 4 Coning plant Covina ple 000 Heat repoa Equpmentiag istercocled chis 001 w EE 4 oe Equipment catego Watered Hout anben wet buba Egiptio 15r Cereus A F Thaae Seguenongyea Snes type oe i Heat Riepection Library Equamert iene fete Uineuding curve g1Ss Mastin Te wF Common hte aan Patloe Miliy Ioir w P apy fi IF arani Enei consumption 01 oss lk chet Alor Fid twee vor SY Note Use the Library J Template Editors program to view the characteristics of predefined equipment orto add custom equipment Refer to online Help for additional information about eT A i Assignment of Ced Losi individual fields associated Fe Man FF Indeed raprata F Options verdidation l T Dee evap et Akap FE Mibe cookng kul of Full Power with the equipment TRACE 700 User s Manual e CDS PRMOO01 EN Chiller tower optimization Independent studies of the relationship between the cooling tower and chiller demonstrate the importance of balancing chiller and cooling tower energy As Figure 3 15 illustrates the optimal condenserwater temperature for a specific chilled water plant depends on both chiller load and ambient conditions Figure 3 15 Chiller tower energy consumption 1 200 1 000 1 550 ton cooling load at 65 F WB 800 1 160 ton cooling load at 59 F WB 600 400 730 ton cooling load at 54 F WB power consumed by chil
383. led water plant kW 200 60 64 68 72 76 80 84 88 set point for entering condenser water temperature F Coldest condenser Highest cooling capacity water that the tower available at this condenser can produce at this load water temperature and wet bulb During many points of operation the optimal condition is not the lowest water temperature that the cooling tower can produce To reduce the overall energy consumption of the chiller tower combination it is important for the system designer and plant operator to evaluate the use of system level controls that establish a set point temperature for the tower sump based on ambient and load conditions CDS PRMOO1 EN TRACE 700 User s Manual Cooling and Heating Plants 3 59 Chiller tower optimization Application considerations m Load ambient conditions and the part load operating characteristics of the chiller and tower ultimately determine the optimum tower control temperatures for a given installation Information sharing controls are key to successful optimization m Energy consumption of helical rotary Screw compressors drops quickly with reduced head pressure condenserwater temperature The optimal towersump set point for these compressors is therefore lower than for centrifugal compressors m Chiller operation at elevated towerwater temperatures though efficient may cause adverse effects over time Operating with a higherthan normal pressure differential betwee
384. lehest 306 Min Flew Chef aut Directives Crehumedihcaton Methods ipin 3 nvulston ook Te fie w a nrg F Hieum room relative Hamidu Mian okey tel cere dikes beer ether hosting a chilled eater cod dereud ihare cheba ate eater at Terkel cote rattle r Viseble Fan Speed fot capacity conina Syttem Samulator only M F Ma F Tupah ches temperate LS F diania Samer Humbe of fan speeds Porm Peacen awad Pencent airflow of medum speed Humbi Dengi humedity ite diaesa Fark Hirmu rogar pelatres humidity E 5 ine JOO ors Deea O empia O E Advanced Usage and General Modeling Tips Selecting a DX unit using TRACE 700 output TRACE 700 User s Manual e CDS PRM001 EN The following numbers will be used during the selection process 6 After recalculating the Total Capacity 372 Tons 446 1 MBh file the new results can Sensible Capacity 356 6 MBh be used to select the unit Supply Airflow at Space Sensible Peak Load 14 863 cfm Supply Airflow at Cooling Coil Peak Load 14 676 cfm Entering Coil Conditions DB WB 76 9 F 63 0 F Entering Main Heating Coil DB 48 6 F Altitude from Title Page report 812 feet mj ire 2t sua s iier so oo eon eS 0099 84589298588 Ty 7 i ij ae stl oootsbheia bii 7 After inputting the new results in TOPSS click Run and view the a 3 f ii is pagang ii Bh l i iti tf i i Ti oot TA ii ii uco
385. lified model for load design and energy analysis are discussed below Figure 6 2 Large Room Example Conference Room Offices South Energy analysis In the building above five separate thermal zones are shown Inside of the zones are thermally similar rooms The loads positive loads Indicate heat gains negative loads indicate heat losses for the zones during a typical fall morning are as follows Table 6 1 Zone loads Internal Loads Envelope Loads Space Load Office North 10 000 Btu h 16 000 Btu h 6 000 Btu h Office East 6 000 Btu h 8 000 Btu h 2 000 Btu h Office South 10 000 Btu h 12 000 Btu h 2 000 Btu h Office West 6 000 Btu h 10 000 Btu h 4 000 Btu h Conference Room 16 000 Btu h O Btu h 16 000 Btu h Total 48 000 Btu h 46 000 Btu h 2 000 Btu h If these five zones are modeled separately all of the offices will be in heating and the conference room will be in cooling CDS PRM001 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 45 Modeling large rooms and zones However if these five zones are modeled as one large room then 2 000 Btu h of cooling and no heating are required In the case of the one room model the heating and cooling energy consumptions would both be underestimated Load design In load design the above situation does not apply because the cooling and heating calculations are done separately and internal loads are typically neglected for heating design H
386. ling for LEED Energy and Atmosphere prerequisite 2 EAp2 Minimum Energy Performance This prerequisite for achieving LEED certification requires the proposed building meet a minimum standard of energy efficiency Energy and Atmosphere credit 1 EAc1 option 1 Optimize Energy Performance TRACE 700 provides many features that help evaluate a building s overall energy use and determine its efficiency These features are discussed in length during the C D S ASHRAE Standard 90 1 LEED seminar Contact C D S for more information regarding this training class Energy and Atmosphere credit 5 EAc5 option D Measurement amp Verification The model used for EAc1 can be used towards achieving this credit Reference the International Performance Measurement amp Verification Protocol Concepts and Options for Determining Energy Savings in New Construction Volume III for detailed information on how to appropriately adjust the model from EAc1 to be used for this credit Energy and Atmosphere credit 6 EAc6 Green Power The model used for EAc1 can identify the baseline electrical consumption needed to achieve Green Power credits Water Efficiency credit 2 WEc2 Innovative Wastewater Technologies The Equipment Energy Consumption report shows the amount of make up water associated with the cooling coil condensate This information may be helpful in achieving this credit Indoor Environmental Quality prerequisite 1 EQp1 Minimum
387. ling schedule defines whether fan cycling is permitted and if so how it is implemented m Cycle with all loads Fan operates continuously when any building load exists regardless of occupancy fan stops when the load is satisfied m Cycle with cooling loads only Fan operates continuously when a cooling load exists regardless of occupancy fan stops when the cooling load is satisfied When a heating load exists the fan runs continuously m Cycle with heating loads only Fan operates continuously when a heating load exists regardless of occupancy fan stops when the heating load is satisfied When a cooling load exists the fan runs continuously m Cycle with occupancy Fan operates continuously during occupied hours Fan is off during unoccupied hours occupancy is less than 5 percent but starts if cooling or heating is needed and then stops when the load is satisfied E No fan cycling Fan operates continuously whenever the utilization percentage in the fan not fan cycling schedule is greater than O percent fan is off when utilization is O percent CDS PRMOO01 EN TRACE 700 User s Manual System Control Strategies 5 5 Fan cycling Optimum start and stop Optimum start and stop is a control strategy that leverages the thermal capacity of the building to reduce the hours of equipment operation For example lightly constructed wood frame buildings respond more quickly to the operation of the HVAC system than buildings construct
388. lity to model this ventilation strategy Refer to ASHRAE Standard 62 1 on page 4 91 for more information 6 82 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN Modeling for LEED Create systems Construct the HVAC systems found in the proposed building Chapters 4 and 5 of this manual provide information regarding various system types and control strategies The Create Systems section of TRACE defines how supply air is delivered and determines where coils and fans are placed in the air stream It does not dictate the type of equipment DX chilled water etc or how many pieces of equipment are installed Note Energy Conservation Measures ECMs found in a proposed building may include supply air temperature reset economizers optimum start stop control strategies and various forms of energy recovery Utilizing these strategies singularly or in combination could produce significant energy savings over the life of a building TRACE 700 has the capabilities to model these and others Refer to Chapter 5 System Control Strategies for more information Assign rooms to systems A critical step in any TRACE model involves appropriately assigning rooms to their associated systems Zoning of rooms on page 6 47 contains detailed information on this important step Create plants Select the cooling and heating plants using the custom equipment you previously defined in the TRACE libraries
389. ll pretreat the outdoor air for all of the rooms and zones assigned to the airside system This is the most common choice for dedicated ventilation systems The System Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Zone Each zone or room assigned directly to the system will get a separate dedicated ventilation system The Zone Checksums or System Component Selection reports should be used to size the dedicated ventilation unit system so the coils should be set at the System level Note For additional details on Systems refer to the System Type Characteristics in online ner Room Each room will get a separate dedicated ventilation system The Room Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Same level as main cooling coil The dedicated ventilation unit will be placed at the same level as the main cooling coil The System Component Selection report should be used to size the dedicated ventilation unit Same level as main heating coil The dedicated ventilation unit will be placed at the same level as the main heating coil The System Component Selection report should be used to size the dedicated ventilation unit IP Create Systems Fan Overrides Akana System dergon Fan Coh md DA Fano 8 On the Fans tab input Fan eyeing schade Cycle mih eccwancy the fan type and the total static pressure for the
390. ller to which it is assigned 3 44 Cooling and Heating Plants available when the ambient wet bulb AWB temperature is less than the design return chilled water DRCVV temperature plus the heat exchanger approach HEA temperature that Is AWB lt DRCW HEA m The cooling tower must be designed for winter operation m Vater entering the condenser must be maintained within the temperature limits specified by the chiller manufacturer Related reading Multiple Chiller System Design and Control Applications Engineering Manual Trane literature number SYS APM001 EN Chilled Water Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRCO16 EN A New Era of Free Cooling Engineers Newsletter volume 20 number 3 Sample scenario A chilled water plant includes a three stage centrifugal chiller and a plate and frame heat exchanger that has a 3 F approach The following illustrations demonstrate how to model this plant Cooling category W ater couled dia Commerts CVHE CENTRIFUGAL CHILLER 170 000 TONS Equemernt ype Stage Centtugsl Cookng type Centrtugs Man chied nlermeed 0 F To change the approach Lond shedding economies ho temperature choose a plate Fuel souca uiy _and frame type here Fuel bape Electric Minimum operating 95 Evanina mE pierog Ha E wap grea elincreennss X Thema siorsga bpe None Heen conde heat
391. ludes overrides that restore normal operation before the end CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 43 Demand limiting Use the Library Template Editors program to define when the on peak periods occur 1 5 In the Schedule library create a new Utilization schedule and rename it as On Peak 2 Assuming that on peak periods only occur on weekdays from 11 a m to 4 p m define the cooling and heating design schedules as shown here 5 44 System Control Strategies Demand limiting of the demand limiting period if the space temperature exceeds a predefined limit Application consideration Ensure that the building automation system Monitors the entire electrical load b Controls the HVAC system and any other electric devices that contribute to the energy consumption of the building Includes a demand limiting function d Provides a means to ensure that occupant comfort takes precedence over electrical demand Sample scenario The targeted annual electrical demand for a building is 1 400 kW Determine the effect of limiting demand to 1 200 kW during on peak periods Assume that Space temperature can drift as much as 3 F from the set point Heating equipment will operate as needed to ensure that the space temperature remains within this range Schechule r 2i5 Schedule type Usen p Schade Definition P Slat End Desenpiion On Peak 1 Month rsy 7 Derea Simudstion ype
392. m this coil leaving temperature is fixed The psychrometric analysis uses a least squares fit estimate for the coil curve as It iterates to determine return air temperature coil leaving temperature and supply airflow The value of 26 333 cfm in the Airflows section of the report comes from the Space peak sensible load which in this example occurs at month 6 hour 18 Q space sensible DSHP x AT space 544 104 Btu h 1 0924 x 75 F 56 1 F 26 354 cfm supply airflow design As is listed at the top of the Checksums report the system is a variable airvolume system Therefore the airflow may be different at the time when the load on the coil peaks than at the time when the space peaks This is the primary reason for the discrepancy in Coil Airflow versus Supply Airflow In a nutshell the supply airflow 26 333 should be used to select the fan and the coil airflow 24 227 should be used in the coil selection The problem however is in selecting an air handler when the fan and coil have different peak airflows Selection of an air handler prompts the user for only one airflow Therefore the fan airflow the higher of the two should be used to select an air handler Conservative selections should also use the coil airflow as a 6 78 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Selecting a chilled water cooling coil using TRACE 700 output check for coil leaving conditions dry bu
393. m 111 Mutic Room Infa FP z Teate foe i i t pohedule ER Chemis hol sara a epee ae nt hhean Entries in the Utility Rates amp Life Cycle Costs Cice e ek C 5ks Pasado section can be redefined for each alternative in Yew coat Doge Botan T i pen Cn a project Create schedules Schedules play an important role in load simulations and energy analyses They define when and for how long internal loads and system events occur both of which affect energy demand and consumption CDS PRMOO01 EN TRACE 700 User s Manual Program Overview 2 19 Performing basic tasks Five types of schedules are predefined in the TRACE 700 Schedules library E Utilization schedules define the timetables for internal loads occupancy lights infiltration miscellaneous and the air distribution side of the HVAC system fans coils controls E Thermostat schedules establish the cooling and heating set points for each hour E Time of day schedules distinguish peak mid peak off peak and superoff peak hours permitting economic analysis of energy costs E Thermal storage schedules define when the operating modes for thermal storage equipment occur E Equipment operation schedules define the hours of the day that mechanical cooling and heating equipment is available for operation The Library Template Editors program lets you view the attributes of each standard schedule and create
394. m and maximum values on the Temperatures tab of Create Systems If a Supply air temperature is input and the supply air flow is not input TRACE 700 solves for the supply airflow using the sensible heat equation The program will also determine the resulting room relative humidity based on the specified supply air temperature and will report it on the Psychrometric State Points report It a VAV system is being modeled the user can enter the Block Cooling Airflow on the Advanced tab of Create Systems TRACE 700 will calculate the system level cooling coil leaving conditions using the sensible heat equation The program will also determine the resulting room relative humidity based on the specified airflow and will report it on the Psychrometric State Points report If a system with a room level cooling coil Such as a fan coil system is being modeled and the user enters room level airflows TRACE 700 will calculate the room level cooling coil leaving conditions using the sensible heat equation and the input airflows The program will also determine the resulting room relative humidity based on the specified airflow and will report it on the Psychrometric State Points report If a system that has a zone level coil single zone VTCV or a system level coil terminal reheat that uses peak fan sizing is being modeled there is currently no way to specify a system level CFM Note that the peak fan sizing method is typically used for
395. m off peak demand in January and that 65 kW is the maximum on peak demand and 50 kW is the maximum off peak demand in February The charges from the utility company would be as follows January E Minimum demand 100 kW x 80 80 kW Because the 80 kW on peak demand during January is equal to the 80 kW minimum then the minimum demand does not apply mM On peak demand charges 80 kW x 10 45 kW 836 00 m Off peak demand charges 60 kW x 6 05 kW 363 00 February E Minimum demand 100 kW x 80 80 kW Because the 65 kW on peak demand during February is less than the 80 kW minimum then the minimum demand does apply and 80 kW would be the demand for February mM On peak demand charges 80 kW x 10 45 kW 836 00 E Off peak demand charges 50 kW x 6 05 kW 302 50 Assuming that 500 therms of gas are consumed in January the charges from the utility company would be as follows January m Customer charge 10 00 M Gas usage charges 500 therms x 0 505 therm 252 50 E otal gas charges 252 50 10 00 262 50 CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 161 Creating utility rates Stepped rate with a kWh kW flag The kWh kW flag activates what is also called a floating cutoff This allows the cutoff levels for each month to vary depending on the maximum demand for each month Note Only the consumption portion of the rate structure Is shown below For examples of sta
396. men Powers Cere __bodhate Utility Ges z Delete Rate inson s x medie ise schedule eee a Note Do not use a default rate Northern Coa icu Lie Tans Power for example The default rates are inaccurate and intended only as examples of how to input custom rates For instructions on how to create utility rates please refer to Utility Rates amp Life Cycle Costs B Creating utility rates on page 6 150 Advanced Usage and General Modeling Tips 6 119 Inputting an existing load profile i i Aha Boat pou chet 1 Rawle and miadi your eqeancnend aririas Badaki rere eerste iep Adelie Sela nai I Calculaia aid wii tur 10 C 10Click OK on the message that comes up 11Click Enter Project Information and enter any desired data 12Click Calculate and View Results then click Select All and finally click Calc Now Cakukihe dd View Resti 13Do one of the following a After the calculations have completed close the Chiller Plant Analyzer Summary report click View Results and then click Profiles and Energy Consumption The TRACE 700 Visualizer should open ee Or b After the calculations have completed close the Chiller Plant Analyzer Summary report close Calculate and View Results and click Modify Load Profile on the Actions menu The TRACE 700 Visualizer o b w gt w gt b gt TRACES C rla Plant Analyzer lor the exclusive use by Fit Edt Actors Tps Libr
397. mp Refer to Flow based condenserwater reset on page 5 29 Thermal storage _ lt or Equemant schedule Avedatie ron TRACE 700 User s Manual e CDS PRMOO01 EN Definitions for water cooled chillers in the Cooling Equipment library include design entering and minimum operating temperatures for condenser water Use the Library Template Editors program to display the values for a particular chiller Cooling category wae coded die Comments 7190 tore wth heat recovery 105 deg Equipment ype 2 Stage Cent wa Hest Roc 105 HW E Cooling Equipment Options Hw EqiOvth Chile reater bern Desapiinrery je F Diere hi F Cordancer tame Despena 05 F Minmumcoesing 6 TF sect condenas hes Tomimenosiype Hang plant E CDS PRM001 EN TRACE 700 User s Manual Cooling and Heating Plants Double bundle condenser heat recovery 3 53 Evaporative precooling of condenser air Precooling the condenser air stream can increase the efficiency and capacity of mechanical cooling equipment The cost effectiveness of this option is directly related to the ambient conditions in which it is used Generally the drier and hotter the climate the greater the potential savings Evaporative precoolers primarily consist of porous absorbent material continuously saturated with water Commonly used with air cooled equipment such as rooftop air conditioners the precooler is mounted on the entering air side o
398. mperatures as cold as 35 F Adding an optional head pressure control can extend operation to O F and may be required to enable low ambient cooling in applications that use changeover bypass VAV controls 3 64 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Airto air heat poump system m lo reduce drafts during heating operation use diffusers that control air velocity and throw The heating supply air temperature is usually lower for heat pumps than for other types of HVAC systems m Some air to air heat pumps include barometric relief gravity actuated dampers that open as the building pressure rises Whether barometric relief is sufficient during economizer operation depends on the characteristics of the airdistribution system When making this determination be sure to account for the return air pressure drop Sample scenario A dedicated air to air heat pump satisfies the airconditioning needs of each retail store in a strip mall Electric resistance heat serves as a backup when the heat pump is unable to satisfy the entire heating load for the store Alheira 1 piba deenphon Syctern fn lecial Heat Purp Wais Vakai i To model each air to air heat Contern Vehone iling Indus pump 1 or Create an airside system and define it as an incremental heat pump Incremental means that a separate heat pump serves each controlled space Dedicated 04 TemgvHumidty Fora Cody Schemati
399. ms are also used for sensible cooling only no latent cooling no dehumidification Active chilled beams CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 79 Chilled beams 4 80 System Design Options Chilled beams differ from passive chilled beams because they have an integral air supply This primary air passes through nozzles at a high velocity As a result air is induced from the space through the cooling coil Because of the induction process active chilled beams provide more cooling capacity than a same sized passive chilled beam By definition active chilled beams are combined with a separate primary air system that 1 delivers the required amount of ventilation air to each space 2 delivers the air dry enough at a low dew point to offset the space latent loads and maintain the indoor dew point low enough to avoid condensation on the chilled beams and 3 delivers enough primary air to induce sufficient room airflow to offset the space sensible cooling loads Although active chilled beam systems include the ability to provide some heat Ing cooler climates may necessitate additional heating systems e g baseboard heating Figure 4 19 Active chilled beam ceiling primary air induced air Application considerations Chilled beam systems require smaller ductwork air handlers and fans than a comparable VAV system However energy use depends on climate operating hours and building use
400. mum and maximum cooling supply air dry bulbs be set equal to each other to fix the value for the cooling supply air dry bulb This is suggested because TRACE 700 cannot psychrometrically solve for the cooling supply air dry bulb when an energy recovery device is attached to the Return Outdoor deck Please read the FAQ and Oversizing and Undersizing sections of the manual for the ramifications of fixing a cooling supply air dry bulb Energy recovery transfer devices are generally applied at higher airtlows higher face velocities than what the manufacturer submits for ARI certification For example if a wheel is rated at 400 fom a typical sensible heating effectiveness is around 74 percent However it is likely that this wheel will be applied at a much higher airflow 600 700 fom which will decrease its effectiveness The user should work with the manufacturer s representative to determine the effectiveness of the device at the desired airflow and at 75 percent of the desired airflow and then input these values for the 100 percent and 75 percent airflow points for accurate modeling Refer to Table 4 1 for recommendations on energy recovery applications in different scenarios Table 4 1 Applications for Air to Air Energy recovery Ventilation System Energy Recovery Technology Supply air Supply air Outdoorair Source Temperature Tempering Preconditioning Dedicated Cold Not applicable Sensible or total outdoor air eS Neutral Sensi
401. n Parameters fab Len oa a The Daylighting Geometry Type tells the program how the glass was input and is used to determine the fraction of the available daylight passing through the glazing area that can be used to offset the power consumption of the electric lights b The Atmospheric Moisture represents the amount of perceptible water vapor in the atmosphere and affects the calculation of the luminance of clear skies this is not the amount of rainfall c The Atmospheric Turbidity is a measure of aerosols particulate pollutants and water droplets in the atmosphere and affects the calculation of the luminance of clear skies d The Inside Visible Reflectivity is the fraction of visible not solar light that is reflected rather than absorbed by the opaque surface This value is used to help calculate the luminance of both natural and electric lighting within a space CDS PRMOO1 EN TRACE 700 User s Manual System Control Strategies 5 37 Daylighting 6 Click the Daylighting Controls tab which contains standard and user defined Daylighting Control Strategies No inputs are required on this tab for the example scenario because it is using a default control type Note To create a custom controls template click Copy and enter a description This activates the fields under the Controls and Geometry sections Note Values under the Controls section should be input starting at the top and working down 5 38
402. n Outdoor Deck conditioned outdoor air is mixed with the return air in the main unit s Plenum conditioned outdoor air is delivered to the plenum above the spaces Cancel Room Direct conditioned outdoor air is delivered m directly to the spaces This can also be used to model a the delivery of conditioned outdoor air to dual duct y VAV boxes where it mixes with conditioned j recirculated return air j Chee sted Ventilation Locations rer i Ermia VIEEE Create Systems Dedicated Ventilation Abematrve System dercription wSHP and DOAI Y Water Source Heat Pump emmu Configuration Dehumdiy and Rehest Hast Control method F cone Salji Cooling Heating Setpoint Lasts Supply an dy bub high int F Supply on diy bully lowe beret i Cooling SA dew point high ima Cooling SA dew pout kow imi F Dede ated Ventilation Locators Cooling Heating Design Setpoint System The dedicaied ventilation unit will be placed at the system level It will pretreat the outdoor air for all of the rooms and zones assigned to the airside system This is the most common choice for dedicated ventilation systems The System Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Zone Each zone or room assigned directly to the system will get a separate dedicated ventilation system The Zone Checksums or System Component Selecti
403. n be captured in the model The Base Utility Misc Accessory tab of Create Plants on page 6 17 details how to model the energy use from items such as parking lot lights and elevators Additionally receptacle loads are modeled on a room by room basis as miscellaneous loads through the Internal Loads tab of Create Rooms Apply daylighting if applicable Utilizing this strategy could reduce the lighting load and equipment size required for the space If this strategy Is to be used please refer to Daylighting on page 5 33 for more information Define utility rate structures Once the proposed building model is complete defining the utility rate converts the building s energy use into costs The resulting cost will be compared against the baseline building s energy cost ultimately determining the number of points achieved under EAc1 Appendix G allows the user to model either the local utility rate structure or the average energy prices reported by the Department of Energy s DOE Energy Information Administration EIA http tonto eia doe gov state In either case TRACE provides the ability to model most utility rate structures Refer to Creating utility rates on page 6 150 for more information 6 84 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Modeling for LEED Import weather ASHRAE 90 1 2007 requires the analysis utilize a full year weather file The standard weather files
404. n corba methodi Mainheatingten aiai a Aucahary tan Supply Aa Resat F Archery lan ric Fan Reret op Syeter Leved Ventilation Ovemdes root replet JAvotabte 100 2 fio 3 FF Use sitom delak outude an reset Aatlow Sum of room romnal vertiiahen r tome tae pl ow Supp a DG coolngkw atotidenros Schedde Aviate 100 dampers Supp at OB cooling high a atude of OF The should repeeterd the combed reantance of the capel H emits and the reed Ibar parel and shoudd NOT include any an fe reantance These controls ace ignored uniess the madiay cla of hig col capacity overrides are defined on the Coeste Systema Heating Cod Ovenides saioen TRACE 700 User s Manual e CDS PRMOO01 EN Supply air temperature reset Scenario 2 Supply air temperature reset based on outside air temperature See Figure 5 13 for a graph of this strategy Advan ed Qyebhiona 1 Uncheck Use system Satter deiei VER oat default outside air resetto m r ace ee foro CT cart alee denian input a new reset schedule agen ts a piima te one tt Uredkerfines p rmar tech P A 2 Enter the appropriate Duy Cycing Candace nistana alisios T7 hete Fina g iey peered oclrodiude te r Suppi Duni J thi Losses values for the air reset es L anina i Maima etme OO mt Diierriei birria beah ip factors Oo y schedule ea eo eer daky Codd J Lae Gorda hodi
405. n cycling CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 103 Modeling for LEED schedule provides the most accurate method for controlling the fan operation Scheduling a fan as something other than Available 100 can quickly lead to a high number of unmet load hours m Verify that diversity has been accurately defined One way to reduce design coil capacity for VAV systems is to apply a diversity factor for internal loads This factor allows you to credit VAV system capacity for shifting loads in a building e g each space has to be designed to handle its worst case loads but at any given point in time there are less than design internal loads in the building If the diversity factors are overly optimistic and do not mesh with the occupancy schedules for simulation coils could be undersized This approach does not apply to constant volume systems To access the diversity input go to the Coils tab of Create Systems m Apply an optimum start schedule TRACE design coil capacities are determined at steady state conditions assuming the space is always controlled to the desired design space setpoint In some instances pull up or pull down loads associated with dynamic building operation can exceed the capacity of a coil These dynamic conditions are not accounted for in the design process A common example of when this might occur is when a building has night setback thermostat controls that all
406. n the evaporator and condenser places a greater burden on the compressor Related reading E Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN m Tower Water Temperature Control It How Engineers Newsletter volume 24 number 1 Sample scenario Condenser heat from a watercooled chiller is rejected to a cooling tower A building automation system governs plant operation optimizing the water temperature leaving the cooling tower to minimize the combined energy consumption of the chiller and tower The following illustrations represent the entries used to model the control strategy for chiller tower optimization Note Of the cooling towers predefined in the TRACE 700 library of heat rejection equioment two include optimized control of condenserwater temperature as well as variable frrequency drives Optimized VFD C tower 10 F represents a 10 F design range and Optimized VFD C tower 15 F represents a 15 F design range 3 60 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMOO01 EN Chiller tower optimization l After creating a cooling plant that consists of a water cooled chiller cooling tower and related pumps pick one of the optimized cooling towers as the heat rejection type yUse the Library Template Editors program to view the attributes of the predefined cooling towers with optimized control a Copy and modify one
407. ndard stepped rates please refer to the stepped rate example on page 6 150 Electricity consumption Customer Charge 200 00 charged each month regardless of usage Rate For the first 100 kWh per kW of billing demand per month m 0 06 per kWh for the first 1 000 kWh m 0 05 per kWh for the next 9 000 kWh m 0 04 per kWh for all over 10 000 kWh For the next 110 kWh per kW of billing demand per month m 0 055 per kWh for the first 1 000 kWh m 0 035 per kWh for all over 1 000 kWh For all kWh over 210 kWh per kW billing demand per month m 0 03 per kWh for all kWh To better illustrate how this rate structure works a sample calculation for two months will be shown first and then the inouts for TRACE 700 will be shown Month Demand kW Consumption kWh January 250 kW 50 000 kWh February 200 kW 35 000 kWh 6 162 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Creating utility rates January The cutoffs are determined by the kWh kW floating cutoffs mM 100 kWh kW x 250 kW 25 000 kWh m 270 100 110 kWh kW x 250 kW 52 500 kWh For the month of January this translates to the following rate structure 0 1 000 kWh 0 06 kKWh 1 001 10 000 kWh 0 05 kWh 10 001 25 000 kWh 0 04 kWh 25 001 26 000 kWh 0 055 kWh 26 001 52 500 kWh 0 035 kWh 52 501 infinity kWh 0 03 kKWh Actual consumption 50 000 kWh from table on page 6 132 Consumption charges 1 000
408. ndenserwater temperature is input accurately and the load profile is realistic then the backup heating equipment and heat rejection equipment may never be activated Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Frequently asked questions Comparing Input data on To compare alternative inputs 1 Open the file in TRACE 700 2 On the View menu click Entered Values 3 Select the first alternative select the section of the program to compare and click Preview 4 Click the envelope at the top of the Entered Values report click Rich Text Format or MS WORD on the Save as type list choose the destination for the export and click OK 5 Select All as the Page Range to export all pages and click OK CDS PRMOO0O1 EN TRACE 700 User s Manual In TRACE 700 it is often useful to compare the inputs of one alternative to the inputs of another Microsoft Word can be used to helo make comparisons of input values easier Sabo DR ee Feet ate Sa AT Project Maija So 4 Tevplates Fle Edt Actions View Options Ubvwies Templates me TRADES 700 CACDS TRACE 700 Projects Compare TRI Abert Sek Windows Haip Do oS e Dem low eee Des eter A Ps wen me pii HETH a HERR o ZT ramie Mowa A x Seg4 n SEAR see toot Advanced Usage and General Modeling Tips Comparing input data 6 37 Choose export file
409. new name WC Helical Rotary Practice Avoid using any punctuation in the name ons 2 EE amp E of Full Load 9 Select Percent for the Load units and the En mal Power units then input the constant condenser temperature unloading curve from the selection Selecting the Load units as Percent will activate the Power units field Be sure to select Percent for both fields before entering values The points for the curve are calculated based on the percent load and kW columns of the selection w Library Template Editors lnj x Fie Vew Opio Window Help eaa E a a E a a EA A ez TRANE Curves Library zial zj Curve Type Coating equpmert power Connumed i WC Helical Rotary Practice 10 Decean Paces tit 70 _ Sov A The unloading curve can be input using several different Note If the units for Load methods curves percent The Cycle Point represents the and or Power are input as percentage of full load capacity at and so on In this case the kW Mbh tons or therms it which the equipment will turn on and AAN E DE is recommended that the off cycle to satisfy the load by percentages capacity of the equipment be input in Step 4 10Click Save and then Close to return to the Cooling Equipment library 6 146 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Creating equipment and unloading curves 11Select the Primary Power co
410. nformation related to modeling a dedicated ventilation makeup air unit Application considerations The air streams targeted for energy transfer usually exhaust air and ventilation air must be situated near each other TRACE 700 User s Manual e CDS PRM001 EN Total energy enthalpy wheel m lotal energy wheels can recover both latent heat and sensible heat with an effectiveness that typically ranges from 65 percent to 80 percent Adding a wheel usually increases the system static pressure by 0 7 in wg to 1 2 In wg m Cross contamination between air streams is possible To minimize air carryover in critical applications add an effective purge arrangement Placement of the fan In relation to the wheel should promote leakage from the outdoor ventilation air stream to the exhaust air stream rather than the reverse m The relatively compact size of a total energy wheel can permit factory installation in air handlers rooftop air conditioners and some terminal devices such as unit ventilators m Climates that economically favor heat pumps are good candidates for successful total energy wheel applications When applied in very cold climates it may be necessary to add preheat to prevent frosting of the wheel Related reading m Airto Air Energy Recovery Engineers Newsletter volume 29 number 5 E Airto Air Energy Recovery in HVAC Systems Applications Engineering Manual Trane literature number SYS APMO003 EN Sample scena
411. ng Pah cubicle oe DE Tite choad repeepent the combered itanna of thes canpest fi E mibe and the ace Moon parse and hadd HOT inchude sny ae fle emit ere gt These corti ane gered unioni Ae cuban chp hig ood copecity geenien ono defined on the Cesme Syctenn Heating Cod Decteien ices fF Create Systeme Fan Overrides Ahim Energy Rate System duoin AER E UFAD VAN wu Baseboard Heating Fan eyeing schedule Cycle wthoceupercy X CDS PRMOO1 EN TRACE 700 User s Manual System Design Options Underfloor air distribution Type Hagh page Guppi er pah fF chest kena He dti Guppi ia Unerioa Plenum Deire stat T 7 Gpe ieribie gamit heaccupecd y E3 Aulay hening cod irwan Alter Frap 5 poten z Hens Supply Aa Fse T Aday ah nefs O lt SF ae a Sa Airflow I Sam of roam rnal wendiistion z r irelease tt Tuppy ae DE tiir k I a puide a OE Sichapchuies Erma 10 daper 4 87 Displacement ventilation A displacement ventilation system supplies very low velocity air to the space via a raised floor system or through low sidewall air outlets As this cool air nears heat sources in the room people equipment etc thermal plumes cause the air to rise taking heat and contaminants out of the breathing zone One of the advantages of a displacement ventilation system is that only the lower portion of the room is actually conditioned typically six feet from the floor while the a
412. ng Systems 2005 006 6 186 gbXMIL results exported from TRACE 700 6 187 Importing a load design Version 3 x or NV EN SIOW 2 TNC ae ot eh hare eh ark earn aera eas 6 189 CDS PRMOO01 EN TRACE 700 User s Manual Contents vii Vill Contents TRACE 700 User s Manual e CDS PRMOO1 EN Q A Brief Introduction Welcome to TRACE 700 comprehensive analysis software that helps you compare the energy and economic impact of building related selections such as architectural features heating ventilating and airconditioning HVAC systems HVAC equipment building utilization or scheduling and financial options Simplifying these detailed analyses lets you optimize your building system designs based on energy utilization and life cycle cost In new construction projects be sure to perform the detailed energy and economic analyses early in the planning process By doing so the building owner and project team can productively use the results of these analyses to facilitate design decisions The TRACE 700 program can also be invaluable for assessing the energy and economic impact of building renovation or system retrofit projects CDS PRMOO01 EN e TRACE 700 User s Manual A Brief Introduction 1 1 About TRACE 700 alls Uninstalling the program 1 2 will not remove your project files A Brief Introduction About TRACE 700 Package contents The TRACE 700 software package includes the following software and
413. ng airflows The calculated results for the airflows can be viewed on the Checksums reports For room level data the Room Checksums should be used to view Ventilation Infiltration Supply Air Return Air Exhaust and Room Exhaust AIRF LOWS Cooling Vent 7O0 Infil 50 Supply 1 000 Min Sto pif h Return agi Exhaust 50 Rm Exh 700 Axil a In all steady state situations real life or simulated the amount of air that enters the space must be equal to the amount of air that leaves the space Two equations can be used to represent this Room level balance infiltration supply air room exhaust return air System level balance ventilation infiltration room exhaust exhaust Four examples will be used to help explain how these equations affect the one room calculation Scenario 1 No infiltration no room exhaust m Ventilation 200 cfm AIRFLOWS m Supply Air 1000 cfm Cooling Went 200 Infil i E Infiltration 0 cfm spay 1 000 MinStop RA E Room Exhaust 0 cfm Return 1 000 Exhaust 700 Rm Exh Axil 0 CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 61 Balancing airflows Based on these inputs TRACE 700 will calculate exhaust air ventilation infiltration room exhaust 200 0 0 200 cfm return air supply air infiltration room exhaust 1000 0 0 1000 cfm Scenario 2 Infiltration no room exhaust E Ventilation 200 cfm A
414. ng and associated service systems for an entire year 8 760 hours of operation The results of these calculations can help you assess how annual energy usage is affected by system design climatic factors operating strategies and mechanical equipment characteristics All TRACE 700 calculations use techniques recommended by the American Society of Heating Refrigerating and Air Conditioning Engineers ASHRAE or produce results that are consistent with ASHRAE recommendations The calculations explicitly describe Climatic data including coincident hourly data for temperature solar radiation wind and humidity including seasonal variations Structural attributes of the building including orientation size shape mass and heat transfer characteristics of air and moisture Operational characteristics of the building and associated service systems accounting for temperature humidity ventilation illumination and control modes for occupied and unoccupied hours CDS PRMO01 EN TRACE 700 User s Manual Program Overview 2 1 E Operational characteristics of the HVAC system accounting for design capacity part load performance and the effects of dry bulb and wet bulb temperatures on equipment performance and energy consumption E Heat generated inside the building from illumination equipment and the number of people inside the building during and after normal hours of operation 2 2 Program Overview TRACE 700 User s Manual e C
415. ng chiller to follow the schedule selected for thermal storage E Discharge 11 a m to 5 p m is a Thermal storage schedule that defines when each tank operating mode occurs 3 24 Cooling and Heating Plants Thermal energy storage Sa e g Aacooed Arc ded Waterco Water lt o chiles untey chiller untey ws m Buder Cooling tower Prenary chided water pure Heating plants Electi Garfred le Heating Plant 002 Defines thermal storage at the equipment level uscd Storage status makes the assigned Kanaa mare equipment available pn when the thermal storage tanks are scheduled to E Schedule Library charge nse ee ETT Schesie or sa Desenption Disehange 11am to 5pm ha a tr am to December See Month arsy December ind Smo yee Reduced pear m odrian Schedule Here is what each operating mode represents Charge Chiller makes ice after satisfying the assigned cooling loads Discharge Ice melts to satisfy the assigned loads storage equipment type determines the control strategy SatLoad Chiller satisfies the cooling load tanks supplement capacity if needed but do not recharge until the next charging period SatNoTank Chiller satisfies the cooling load excess load passes either to the next piece of cooling equipment in the start sequence or to the next hour TRACE 700 User s Manual e CDS PRMOO01 EN Thermal energy storage with multiple chillers
416. npecry Supsa deck Pietun cutdoos of downstream 3 Eride deck Retun Schede Avatatie 100 x Direct efficiency f x Dereci cod schacdhda tie 1 7 n Indeect elicency Indeect col schedule dhe 1 x Stage Ae tode Energy Recowenp T ranster Type Fined plate HOS parallel SA tampeirk Suptdedeck Pietun cuidon a downsteam A Erie deck Renan or Schede Avaiatie 100 E Click Yes to activate energy recovery transfer for design and energy analysis Click No to ignore energy recovery transfer during the design calculation and include it only during the energy analysis simulation Note This message will only appear whenever an energy recovery transfer device is added and Allow energy recovery transfer during design calculations is turned off Paralei F arrPowered VAV Economize E Select Ventilation downstream if the device is located in the outdoor air stream and downstream of the optional ventilation cooling coil Select Return outdoor air downstream if the device is located after the mixed air stream downstream of the main cooling coil Option n port F Max outdoor ak i x Schade Avait Stage 2 Aimowkar Eneogy RecowerwT canater tee nea SY Supada dock Verniso e 4 Ewrtide deck Outdoor E room eass me Schodde hie 1 m Select System Exhaust if main system exhaust Is used exclusively as the exhaust side m Select Room Exhaust if th
417. nsumed curve that was just created required and the Secondary Power consumed curve optional 12Select the desired Ambient modification curve required and the Secondary Ambient modification curve optional For this example the standard library member EQ1500 Amb Mod will be used 13For increased accuracy click Curves to input a custom Ambient modification curve The Curves library will open on top of the Cooling Equipment library and the curve can be input similar to the cooling equipment Power consumed curve Note The Ambient modification a so called ambient relief curve will modity the power consumption after the Power consumed curve has been used to determine constant condenser temperature power consumption Note The Secondary Power consumed curve is only used during the heat recovery tank charging and tank charging and heat recovery operation modes For increased accuracy a second selection can be run on the equipment at these conditions to create the secondary Fie View Opos Window Help POTa se Ror iyi E Cooling Equipment Main Cooling category water cocind chaer Equipment type Heba Rotary Chie Practce Coras Heca aT unloading curve r EOD Crai vel chd walai pump E010 Cral vel ered walai pump Primary Secondary Curre type QA Powerconmumad WC Hebcal Rotary Practice WC Hebcal Rotary Practice Starcsond Ambient modification 1 tage Amb Mod
418. nt volume systems the hourly percentages in the fan schedule are used to calculate fan energy It is recommended that fan schedules not be used or should be input using only O percent for off and 100 percent for on in order to avoid confusion Generally the fan cycling schedule discussed below should be used to simulate most common fan control strategies The fan cycling schedule found in the upper left hand corner of the Fans tab of Create Systems tells TRACE 700 whether the supply fan is allowed to cycle with the cooling and or heating load and whether occupancy is a consideration During normal operation only VAV systems let the fans modulate In response to room load Choosing an entry other than No fan cycling for the fan cycling schedule lets the fans of constant volume systems or VAV fans with minimum stops cycle with the corresponding cooling or heating load The resulting fan energy consumption is proportional to the part load ratio heating load design heating load for that hour For example if the part load heating ratio is 30 percent TRACE 700 simulates fan operation at full bhp for 18 minutes 30 percent of that hour The following types of fan cycling schedules are available No fan cycling No demand related fan cycling occurs the fan follows its schedule in time clock fashion Cycle with heating load only Fan cycles only with the heating load regardless of occupancy Cycle with cooling load only Fan cycles
419. nt Capa i bore a Fan enengy included in packaged equioment Full ined energy rate FP Pritary far Carmel hiin fae Erha Fon Opia wertilation Fan ff Carcieri Nan D Appir same are For best recovery enengy breakout calculate Users may also manually break out the efficiency into the individual packaged components If the manual method is used the individual component energy rates need to be defined in the appropriate place 1 Fan energy rates are accounted for in Create Systems under the Fans tab 2 Condenser energy rate is entered with the associated piece of heat rejection equipment in the Heat Rejection library 3 Compressor energy rate is entered on the Cooling Equipment tab of Create Plants Example Utilizing ASHRAE Standard 90 1 2007 System 5 supply cfm equals 45 000 and the Appendix G designated packaged equipment efficiency is 9 5 EER Table 6 8 1A Additionally the building requires 150 tons of cooling Users may run the design portion of the calculation for the baseline building and then use the System Checksum Report s to determine building cooling capacity and cfm Using this information and Appendix G users may now break out the compressor energy rate from the given 9 gt EER Steps 1 and 2 illustrate the manual system fan power calculation per section G3 1 2 9 of ASHRAE Standard 90 1 2007 As discussed previously TRACE can accomplish this calculation automat
420. ntilation flow and the design ventilation flow When Single Setpoint is selected the intake airflow is adjusted to maintain the indoor CO2 concentration at the minimum CO2 concentration in the space for any population If the OA damper reaches the minimum outdoor air intake flow and the population in the zone continues to drop the OA damper remains at the minimum outdoor air intake flow as specified in the DCV Minimum OA Intake field on the Create Rooms Airflows screen The Outdoor Carbon Dioxide Level which defaults to 400 ppm for each weather location is located on the Weather Overrides screen This value can be changed if desired CO2 sensor locations must be specified within Create Rooms or the Rooms template TRACE 700 User s Manual e CDS PRM001 EN system Control Strategies Modeling examples tn this chapter Airside controls Airside economizers page 5 2 Fan cycling page 5 4 Optimum start and stop page 5 6 Humiditication page 5 9 Fan pressure optimization for VAV systems page 5 12 Ventilation reset for VAV systems page 5 14 Unoccupied ventilation night purge page 5 17 Morning warm up for dual fuel applications page 5 20 Waterside controls E Chilled water reset page 5 24 Condenserwater reset page 5 26 mM Load shedding economizer page 5 30 Miscellaneous controls Daylighting page 5 33 Demand limiting page 5 43 Duty cycling page 5 47 Supply air temperature reset page 5 50
421. ntire system flow becomes the flow rate through each chiller Accommodating this amount of water typically requires an evaporator with fewer passes which compromises individual chiller efficiency The loss in efficiency however can be offset by increased system efficiency The upstream chiller operates at warmer temperatures and a lower system flow rate yields a higher temperature differential Temperature control can be accomplished in several ways The strategy represented In Figure 3 3 uses the design chilled water temperature as the set point for each chiller Either chiller can satisfy up to 50 percent of the total cooling load for the building When the cooling demand exceeds 50 percent of the total load the upstream chiller is preferentially loaded because it will attempt to produce the design chilled water temperature The downstream chiller operates as needed to satisfy the remaining load Figure 3 3 Chillers arranged in series 58 chiller 2 chiller 1 42 F set point 42 F set point system coils L chilled water loop CDS PRMOO1 EN TRACE 700 User s Manual Cooling and Heating Plants 3 9 Series chiller arrangement Application considerations m Reducing the chilled water flow rate for chillers piped in series lowers the pressure drop through each chiller which saves pump energy m Flow and pressure drop limitations make it difficult to apply more than two chillers in series m Ihe difference betw
422. oad people lights and or miscellaneous equipment schedules for ventilation or infiltration in TRACE 700 Because internal loads are typically neglected in heating design calculations per ASHRAE recommendations using an internal loads schedule for ventilation or infiltration will cause ventilation loads to be neglected represented by using zero in the schedule during the heating design calculations Separate schedules for ventilation infiltration and internal loads should typically be used Ventilation schedules should have a heating design definition of midnight to midnight 100 percent and internal load schedules should have a heating design definition of midnight to midnight O percent Because no temperature variation or solar loads are accounted for during the heating design calculation all hours should be scheduled the same TRACE 700 User s Manual e CDS PRMO01 EN Additional items 1 Ifthe schedules do not apply year round definitions can be created on a partial year basis For example if during the summer months the offices are occupied differently a separate definition can be created E Schedule Library Schedule oe Utaeance Deteription Peopie Office Example Semdshon type Reduced poor Sepiemia Decrees Ward Ley Sahada to Sunday Dg Doirdir Reset and lockout tabte s Semaya dool Reet tee aed NOTE The reset and inckouts are avaiable iu the loewang Desg phase rision ventilation rehea
423. odeling errors that are frequently made in TRACE 700 and indicates whether the errors apply to load design energy analysis or both IMPORTANT NOTE The graphics illustrate many but not all of the errors Note The modeling situations listed in this section are not always mistakes but can cause inaccurate results if used inappropriately In certain instances some of these situations can be used successfully for unique modeling needs Contact C D S Support for additional information Rooms Tab of Create Rooms Dsi Corg dytat 72 F Heating diybu 77 F Fleksiren amradly 0 Se Thesincittat Cosina diost u F Heating deiner 55 F Desing ichakda Caa xj Flee maip 1 Room pet ore ho Pioom masseg imela Noe s Ssh donini Bate a erei Acouttic ceing minae 176 hit Fu m Large areas are being modeled as a single space This will typically lead to an underestimation of loads and energy consumption Refer to Modeling large rooms and zones on page 6 45 for a detailed explanation Load Design and Energy E The inputs for floorto floor height and plenum height conflict The floorto floor height is the vertical distance between floors including the plenum height and excluding the floor slab thickness The plenum height is the vertical distance between the ceiling and the floor slab surface of the floor above The CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 3 Common modeling m
424. oding bo H Phi flaca On Create Daybghiireg CEANA Tarnplitet Create Syre Enghsh iP Roi Aniy ooms bo yten E Mabe ST Sibert Amor Sydens bo Plants FJ Picea Attar irene Pti_ ag i FURR Planin Dafina Doorcmic Parameters Se danada Syin Askren Charage Loud Pir arvabirt s Seto iir see Cesnet Change Energy Pararetters Prospch Harihar Tiku F Tiba Diak Trpia A Apher Edi Uire Tengi Sia Ag Entered Priit Miirigihar Baiah Libs ary Vine Delil Ven K Conger Tee i TRACE Ji Prap Irii RE L T Note Availability of certain menus and commands depends on the current view whether a project is currently open and the focus in the current window or dialog box 2 10 Program Overview Program layout Color cues As you work with the program you will see that some of the entry boxes are pale yellow or light gray instead of white and that some values are red or dark gray instead of black Color coding the entries in this fashion lets you distinguish between entries that are changes not advised red background commonly used white background seldom used pale yellow background unavailable light gray background default values from templates red text non template or overridden template values black text TRACE 700 User s Manual e CDS PRMOO01 EN Performing basic tasks TIP The remaining chapters describe how to model common system level HVAC options and control strategies R
425. of Peaks in TRACE 700 Help The supply duct location is return air and the return air path is ducted Advanced button in Create Systems This essentially tells the program that the supply duct is inside the return duct Load Design and Energy The supply duct location is return air and the return air path is plenum If the building does not have a plenum i e by entering the Plenum Height as zero on the Rooms tab of Create Systems these values should be changed to reflect how the air will actually travel in the building Load Design and Energy Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes m The location of the cooling coil has been changed from the default value for the airside system This can lead to the program simulating a system that does not actually exist and may cause erroneous results Load Design and Energy m The ventilation deck location has been changed from Return Outdoor Deck Return Outdoor Deck simulates the ventilation outdoor air being mixed with the return air immediately prior to being sent to the main cooling heating coils This is common in most conventional systems that use dampers to mix the two air paths Any other selection is atypical for most HVAC systems except Room Direct or Plenum for Dedicated Outdoor Air systems that supply outdoor air directly to the space Load Design and Energy Options tab of Create Systems Create Systems Opt
426. of Create Plante ascccer iose race earl dea trace ete cee 6 17 ECONOMICS and Utilities atia e 6 18 Ver Osaran a E 6 19 Frequently asked QUESTIONS ccccccccecceeeeeeeeeeeeesneeens 6 20 Comparing input data siete saccssaccutiaclecaiaise searanvacattionactavess 6 37 No or low heating energy CONSUMPTION s esserceen 6 39 Modeling large rooms and ZONES ccccccs sees eeeeeeees 6 45 ENET MAI SIS ian duh lealinis TTN 6 45 Load desig axthateisncaccotnsniaureiiguisnd tea ernest nnceens 6 46 FON OT TOOWAS Satie Satoh aie ea ca tecsdeas Siesta catindntan teats 6 47 ROOM and ZONE ASSIGNMENTS n 6 47 System level COINS hic aiaawn avian iaiesieneiiaanaes 6 47 LONGEVO CONS ekaan eao 6 48 Room level coils fan coils 6 49 OVEISIZING and UNCESSIZING cccccceceeeeeeeeceeeeeeeaneees 6 51 Balancing AIM OW Sarean cto a Gist EN 6 60 Selecting a DX unit using TRACE 700 outpult 6 68 Selecting a chilled water cooling coll usma TRACE 0OOUTDUL a ee 6 74 WodeInG Tor LEEDO surdina eae 6 80 Compressoronly energy rate 6 96 Quick building inputs via the New File Wizard 6 110 Using TRACE 700 ChillerPlant Analyzer 6 114 Inputting an existing load profile 6 118 Creating spreadsheets and tables from calculation results TRACE 700 Visualizer 6 122 USN VEN OlalCS ictal omsinerdcunmereriiicmsininciencecrtvncetett 6 125 Creating GITEINALIVES stip costes aa a 6 131 Creating SCHECUIES ficiicc
427. of Trane which is a wholly owned subsidiary of Ingersoll Rand The following are trademarks or registered trademarks of their respective companies Acrobat Reader from Adobe Systems Incorporated CALMAC from Calmac Manufacturing Corporation Pentium from Intel Corporation Windows and Microsoft from Microsoft Corporation LEED from the United States Green Building Council 2010 Trane All rights reserved Contents Chapter1 A Brief Introduction POUT AC ESO Oise si cactrtacinte tie tietetaladaogn siete a 1 2 PACKAGE COMET US secant ache cccvacseatdecuntncdnhuiie seewe untemaet 1 2 stalling TRACE 700 c A ea 1 2 starting TRACE 700k reee ieee aT 1 2 bearmnino TRACE OO aiar e ecto eee le 1 3 TRACE 700 terminology sscecreeerrrrrrerrrernen 1 5 Chapter 2 Program Overview CaleullatiO ONES ES carena ia a 2 3 Phasel LOGO CSSION ras e e aa thee ducks 2 4 Phase 2 oystem simulatio aiei n 2 4 Phase 3 Plant equipment simulation 0 2 5 Phase 4 Economic analysis cc cece ecee eect eeeeeees 2 5 FOO Ord AV OU thru aston se ann tects adetoannias tte atta aaninntes 2 6 VOWS eter aetna aia ee eee eee ne atten 2 6 Other workspace elements mrerdriiiiiriusisiaieiina 2 9 COO CUES e a cadet Seneca vent gede iaete 2 10 Performing basie TASKS usien leani a 2 11 Provide weather information cccceeeeeeeeeeees 2 11 Create temp aE Sunna N 2 12 Crete TOON eaae e Gear E 2 13 Creates VS LOIS
428. of the two air streams and releases it in the cooler air stream Latent heat transfer occurs as the medium collects moisture from the more humid air stream and releases it in the drier air stream Figure 4 5 Total energy wheel exhaust alr H building exhaust air y dry ventilation air outdoor air Like other energy recovery devices total energy wheels can yield significant energy savings in systems that exhaust large amounts of air Figure 4 6 and Figure 4 7 on page 4 16 show the typical arrangements for total energy recovery in mixed air and dedicated ventilation systems In Figure 4 6 which shows a mixed air system total energy recovery can be used to precondition the outdoor air CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 15 Total energy enthalpy wheel 4 16 System Design Options Figure 4 6 Mixed air arrangement EA RA OA SA Parallel recovery stream to stream In Figure 4 7 which shows a dedicated ventilation system total energy recovery is often used to precondition the outdoor air Figure 4 7 Dedicated ventilation arrangement EA OA SA Parallel recovery stream to stream The arrangements in Figure 4 6 and Figure 4 7 can be modeled using TRACE 700 Figure 4 6 and Figure 4 7 are input identically however a dedicated ventilation unit must be input to accurately simulate Figure 4 7 Refer to Dedicated outdoorair systems on page 4 45 for i
429. om the boiler 1454 Finally assign each coil load to the appropriate plant CDS PRMOO0O1 EN TRACE 700 User s Manual the selected heat pump refer to page 3 67 determines when the boiler turns on to maintain the condenser water temperature To view or alter this entry use the Library Template Editors program Assign System Coils Ms Ground source hes pump GT Cookers System GSHP E Main Costing Coa lias Backup bode E Man Hesting Cot Cooling and Heating Plants Ground source heat pump system 3 75 Central geothermal chillers A central geothermal system uses the earth as a heat sink and energy source to provide cooling and heating Unlike a distributed ground source heat pump system a central geothermal system uses centrally located chillers instead of small unitary heat pumps distributed throughout the building This system allows greater freedom of airside system selection as heated and chilled water can be distributed to system coils throughout the building Figure 3 20 Central geothermal chiller system Trane bidirectional cascade Q O TE heating H y load _ E ground level 4 6 ft to additional grids 100200 ft Temperatures at this depth typically range from 45 F to 65 F Application considerations E Inputting the entire cooling and heating load is critical for chiller selection and modeling Include all end use components such as domestic hot water refer to Domestic hot wat
430. on throughout this period Fou The optimum start stop strategy for the central fan would be implemented by a building automation system BAS In the Create Systems window of your TRACE 700 project 5 on Click the Options tab and click Advanced Options to display the optional airside control strategies 6 Enable optimum start and optimum stop by selecting a schedule for each control strategy 7 While still in the Create Systems window switch to the Fans tab and select the desired operating schedule for the supply primary fan 5 8 System Control Strategies Optimum start and stop E Schechile Library Schedule type Utzon E Schedule Defition Stat End Description Operum Siro 3 Honth isy reee Simsion ype Reduced pex nie Dw yeafEoara aon veaa x Comments ee Jaruay December Satuday to Sunday Heating deagn A percentage of 0 restarts the fan if any of these conditions occur between 5 p m and 6 p m E Create Syitems Options ex ba ajaa riaj l Ain Energy e Opimue sst Opis Sian 6 Space serabte gina tocccupindige oT a Optimum tap Orima Stop J Uretertens pinra gn hend f e Tea ai Duty ycing Cireda tree eeta e of amed fone FET ntn Suia deck verti Der petuchedte formu Sopi Ouct Other Lorene F dimba cee ia Panon ergh jj mses Upomesre nomna leat age h acton Mamm tme manson Domnaeam constant makagehacton f x Erai
431. on calculated during the plant equipment simulation and your entries which describe utility rates system installation cost mortgage life cost of capital and so on CDS PRM001 EN TRACE 700 User s Manual Program Overview 2 5 Calculation phases Program layout Click a task button to display the related entries in a tabbed worksheet 2 6 Program Overview Program layout Now that you know how the program is organized functionally this section acquaints you with how the program is organized physically Views Performing a complete energy and economic analysis of a building requires details about the building the system and the kind of equipment used as well as information about financing and costs The TRACE 700 workspace organizes these entries In the following three ways Project Navigator view organizes your entries by task Each task in the analysis process Is represented by a button on the floating Project Navigator palette Clicking any of these buttons opens a tabbed worksheet that prompts you for the information needed to complete that step Refer to Figure 2 2 Figure 2 2 Project Navigator view we TRACE 700 CACDS TRACE TOD Projects Tutorialire 47 1RO Fle Edt Actors View poa Lissie Templates Aberatives eup Window Help 2 X Project Navigator Sy EJ Enter Propet Information i A Select Weather Infomation La Crosse wicoro Rerkeceve THE A wn bbe be
432. on reports should be used to size the dedicated ventilation unit Room Each room will get a separate dedicated ventilation system The Room Checksums or System Component Selection reports should be used to size the dedicated ventilation unit Same level as main cooling coil The dedicated ventilation unit will be placed at the same level as the main cooling coil The System Component Selection report should be used to size the dedicated ventilation unit Same level as main heating coil The dedicated ventilation unit will be placed at the same level as the main heating coil The System Component Selection report should be used to size the dedicated ventilation unit TRACE 700 User s Manual e CDS PRMOO1 EN Dedicated outdoorair systems 8 On the Fans tab input the fan type and the total static pressure for the primary fan the fans in the WSHP units and the optional ventilation fan the fan in the dedicated ventilation unit lay Next define the cooling and heating plants represented by the WSHP system and the rooftop air conditioner 9 Add two new cooling plants and two new heating plants to the Configuration pane 10Drag the appropriate icons from the Equipment Category section to define each plant 11 To finish defining this equipment enter the information from Table 4 7 on page 4 56 on the appropriate equipment tab z2 Finally assign the coil loads of the air distribution system to the proper
433. onden ne TS al ovate en bulira de Pen are 100 region of the country i lekanna the chilled ep wear mul seopecile pump hain click the weather location for the model and click 31 Next oe J W RAE Chiller Plant Analyzer Weather Winand Stop Note If the desired weather location does not exist select a weather location with a similar temperature profile or refer to Adding weather locations and activating the 8760 calculation methodology on page 6 167 for directions on importing new weather locations in TRACE 700 6 114 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Using TRACE 700 Chille Plant Analyzer 5 Select the type of building to be modeled If the desired building type is not on the list select a building that would be operated similarly The last sentence in the description usually gives a clue to what other types of buildings can be modeled using the profile Note Chiller Plant Analyzer contains load profiles generated from typical building types for each region of the country Overriding the building profile peaks scales the existing load protile 6 Asummary of the data input to this point will appear Click OK 7 Click OK to start entering economic information 8 Input the desired economic information The only required input on this is screen is the utility rate adhe no hours Soho wath corer Sr Tp wre 4 Override the peak
434. oned outdoor air is delivered to the plenum above the spaces Room Direct conditioned outdoor air is 55 Dyb x delivered directly to the spaces This can kikk also be used to model the delivery of hit 0 F conditioned outdoor air to dual duct VAV om fF ks if boxes where it mixes with conditioned ies i tewm recirculated return air Dedicated Vervilaton Scheduler Dede ated Ventilation Locators 6 Deck Room Drect avveskatle 100 System Options Ay x ie venta 100 Seeon Opee Dedicated 0A IerpHumsy TRACE 700 User s Manual e CDS PRM001 EN Dedicated outdoorair systems W Create Systems Dedicated Yentilation fbematirve System description Fan Cols end DOAJ Fan Col 7 Select the level of the aa l emm i i f Conigustion Dahu red chest F Hest Cerra rrestteced Le igoak tar Cry Boul ventilation deck location Forthi f era Haaing Daiign Depart Cooking isting Separ Listi or this scenario one pele fee E ne large dedicated Heung nuggheardybus oe Sencar dep tattoo f ventilation unit will Soir tl S F Coning Sa dew point high kma F we Cooling SA dew pentlwint F condition the outdoor air I Dedicated Ventily Schedules Dede ated Ventilation Locations for all of the rooms ooir cod avaiable 100 Dad Pocen Direi assigned to the Fan Coil J tei i System The dedicated ventilation unit will be placed at the system level It wi
435. only with the cooling load regardless of occupancy Cycle with all loads Fan cycles with cooling and heating loads regardless of occupancy 6 28 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Frequently asked questions Cycle with occupancy Fan cycles with cooling and heating loads but only when the room is unoccupied i e when the people utilization schedule specifies 5 percent or less of design occupancy Note The fan schedules when scheduled at O percent override all other fan related schedules including duty cycling optimum start and optimum stop Example If the system includes an economizer with OA dampers on the RA OA deck and a main fan schedule reads 0 percent for a particular hour the fan cannot be made to come on during that hour by the action of any other schedule Q On the Rooms tab of Create Rooms what is the difference between Thermostat schedules and the thermostat driftpoints and how do they interact A The thermostat driftooints are the temperatures that the room is allowed to drift up to or down to during periods of low or no occupancy If the room temperature starts to go outside the driftooint temperatures the cooling or heating coils will be activated assuming the coils are available to operate TRACE 700 will allow the room to drift up to or down to the driftooint temperatures during the hours in which the people schedule for the room reads 5 percent or less
436. onsumption of the chiller Usually a chilled waterreset strategy raises the set point temperature when the building load is at less than design conditions Producing warmer chilled water lessens the burden on the compressor which means that the chiller consumes less energy Consider a centrifugal chiller with entering and leaving water temperatures of 54 F and 44 F respectively at design conditions and a maximum reset of 4 F When the building load falls to 80 percent of design the water temperature leaving the evaporator is reset upward by 2 F to 46 F If the building load continues to drop the set point is adjusted upward until the maximum reset set point of 48 F is reached 44 F design set point 4 F maximum reset As a rule of thumb each 1 F increase in the chilled water temperature reduces the energy consumption of the chiller by an amount from 1 percent to 1 5 percent Figure 5 8 Example of chiller unloading characteristics 100 90 80 design chilled water temperature no reset TIE design chilled water 39 Cycle point temperature 10 F reset percent of full load power consumption 0 10 20 30 40 50 60 70 80 90 100 percent of full load capacity TRACE 700 User s Manual e CDS PRMOO01 EN lzy After adding a water cooled chiller to the cooling plant 1 Describe the chiller type 2 Review the default pumps and choose a different type if appropriate 3 Specify the full load consump
437. ooling or undersizing of the cooling coil 2 For heating design reports a a positive value denotes underheating or undersizing of the heating coil b a negative value denotes overheating or oversizing of the heating coil 3 Over undersizing is an actual load on the coil that cannot be ignored 4 There are many other situations that can cause over undersizing These situations are all caused by a space being either over or under conditioned due to the system selected the user Inputs or both CDS PRMOO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 59 Oversizing and undersizing Balancing airflows The following one room example will be used to illustrate how airflows are balanced in TRACE 700 where the airflow values can be input and where the airflow results can be viewed Figure 6 7 One room airflow balancing Exhaust Air ACU Ventilation Supply Air Room Exhaust Infiltration Room 1 Ventilation Infiltration Supply Air Main Supply and Room Exhaust can be input on the Airflows tab of Create Rooms Note Supply Air Main Supply typically should not be input TRACE 700 can calculate this value based on the input loads A rian App ASHRAE Sue aiiai ma Tye Cesa Coleg E Ti Heating Schedule Asiak 100 1 Type Heura Tight Const ca o rd TEE Sehed 6 60 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Balanci
438. oposed building as the first alternative helps ensure that such details remain identical between the two alternatives Collect data As with the proposed building we recommend collecting the appropriate data prior to entering information in TRACE A crucial piece of information needed is the climate zone which can be determined using Appendix B from ASHRAE 90 1 2007 This information is needed to determine envelope parameters and some system control schemes 6 86 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Modeling for LEED qP Adjust envelope parameters amp As with the proposed building simply changing the U values for Many of the baseline the various envelope components may not be sufficient building s values can be Appendix G Tables 5 5 1 through 5 5 8 directs the use of changed through Create lightweight materials in the construction of the baseline Users Templates This will may select one of the ASHRAE 90 1 2007 Compliant Envelope significantly decrease the time it takes to build the baseline alternative and make future adjustments much easier Library values to describe the baseline building envelope nonresidential only These library values were created using construction information found in ASHRAE 90 1 2007 and comply with the Appendix G requirement Additionally they correspond to the envelope parameters defined by Tables 5 5 1 through 5 5 8 Changing these envelope paramet
439. or air to the userinput heating dry bulb during the heating season Dehumidify and Reheat Heat a dedicated ventilation unit is used to dehumidify the outdoor air to the userinput cooling dew point then reheat it to the userinput cooling dry bulb during the cooling season or heat the outdoor air to the userinput heating dry bulb during the heating season will be selected CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 57 Dedicated outdoor air systems 3 Select the control method for the unit Because the dew point delivered by the dedicated ventilation cooling coil is reset based on the worst case room Optimize Supply Air Dew Point will be used 4 Input the Cooling and Heating Design Setpoints In this scenario 65 F should be input for the cooling supply air dry bulb 68 F for the heating supply air dry bulb 65 F for the cooling supply air dew point high limit and 55 F for the cooling supply air dew point low limit 5 Select the schedule for the coils and fan in the dedicated outdoorair unit Note If a custom schedule is created for the fan or coils it is recommended to use values of 0 percent for hours off and 100 percent for hours available to run to avoid confusion 4 58 System Design Options W Create Systems Dedicated Yentilation Akamara System description WTH and DOU Dehaes linon a Caa Hiat Coping Heating Deign batpanti Cooling mupp ardybub 1
440. or the rooms plus zones will have been exported to the xml file Ci Fierom aro tnnert 3o Fis of tpt Green Bulking HL Cancel AN Barts F r Moncnine goirt apatite al 4 Ce CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 185 gbXML import and export Importing goXML data in Autodesk Building Systems 2005 Autodesk Building Systenns 2005 NOT FOR RESALE ghML Exarmnphedwg EP Fie Edt View Insert Format MEP Common Window Help OM 2A rae OO F b SRB rk mIRRES SarB SEEE Ja e HSE OSA MEM CBO A LAF Acces 1 Open ABS 2005 and open the drawing file M 4b OM Medel Work j VP Scale COUR Scale 17 I Autodesk Ruihliry Syste 7005 ST POE RESALE pdt amp 2 On the File list click Import from gbXML 3 Select the xml file from which to import the data and click Open 4 TRACE 700 calculation data should now be included with the drawing file 6 186 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN gbXML import and export gbXML results exported from TRACE 700 Room E Space Loads These loads can be found in the Space Loads section of the Room Checksums report E Cooling Skylite Solar E Cooling Skylite Conduction E Cooling Roof Conduction m Cooling Glass Solar m Cooling Glass Conduction E Cooling Wall Conduction E Cooling Partition m Cooling Exposed Floor E Cooling Infiltration E Cooling Light
441. or the ventilation or copy the internal load schedule and set the heating design definition to 100 percent 3 The user has input different ventilation rates for cooling and heating The easiest way to check for this problem is to click Component Tree on the View menu click the Airflows icon on the left side of the screen and scroll through the inputs for ventilation airflow on the right side of the screen If the input values or units for ventilation differ the user will need to correct the inputs Q How is baseboard radiant heating added to one of the existing system types A Baseboard radiant heating can be added to any system if the system does not include this function by default by specifying a capacity of 100 of Design Capacity for the Auxiliary Heating CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 27 Frequently asked questions Coil on the Coils tab of Create Systems This auxiliary heating system will be sized according to the skin envelope load Q What is the difference between the schedule for the fans and the fan cycling schedule and how do they interact A The schedule for the fan found on the right side of the Fans tab of Create Systems tells TRACE 700 whether the fan is available to run that hour or is turned off For VAV systems if the fan schedule is greater than 0 percent the fan is available to run that hour If the fan schedule is O percent the fan is off For consta
442. ore information Related reading ASHRAE Standard 15 Applied to Packaged Split and VRF systems Engineers Newsletter volume 37 number 1 Sample scenario A VRF system is used to condition multiple spaces within a multistory building Electric resistance heat is employed as a backup heating source and the ventilation is handled by a dedicated outdoorair system Both a VRF heat pump and heat recovery system will be illustrated The following procedure demonstrates how to model the VRF airside system cooling and heating equipment as well as assigning the coil loads Aliri 1 Sythe debenetion fag Winches Plafngesardt cums TRACE 700 User s Manual e CDS PRMOO01 EN Variable refrigerant flow system 2 On the Fans tab select VRV Indoor Fan and enter Abbsinatrns 1 l desertion r Vote Pehia V Da 0 5 for the static pressure an E Eg Note If a ducted indoor VRF Dvenide unit is used the static pressure on the indoor fan will be higher Next describe the cooling and heating plants represented by the VRF system and backup electric resistance heat Ee Ai cooled under 001 g Aircooled condenser LTT la Hesg plants la Bechup electic reaitanoe E Electric Pesistarnce O01 3 VRF plants are considered Air Cooled Unitary plants Drag the appropriate icons from the Equipment Category section to define each plant Rename the cooling plant as VRF and the heating plant as B
443. ossible increase in solar heat gain and the possibility of glare from sunlight Related reading For additional information related to daylighting refer to Daylight in Buildings A Source Book on Daylighting Systems and Components at http gaia lbl gov iea2 1 Sample scenario Daylighting controls will be added to all of the perimeter rooms in a building All windows were Input using dimensions rather than percent glass and a standard stepped controller will be used The user would like to find the savings that daylighting will provide for the building Note Assuming that the other default inputs are acceptable this scenario can be modeled in TRACE 700 with as few as three inputs TRACE 700 User s Manual e CDS PRMOO1 EN 700 C CD5 TRACE 700 Projects ASHRAE 62TRE TRC aif x Is To model daylighting ae dm anet ee aa ae oe 1e 1 Start by modeling the first ae Te Two alternatives are not required alternative completely It is e to model daylighting However required that all glass be to determine the effects of input using the same 7 daylighting on a model two method percent or alternatives are recommended dimensions for daylighting and will be used in this example For more accurate ACE 700 C CDS TRACE700 Projects ASHRAL 627TRO TRO E modeling of daylighting the dimensions method is recommended After Alternative 1 has been completed a second alternative can be created with daylighting
444. ot satisfied a direct evaporative cooling coil 65 percent effective activates Any remaining load is handled by the conventional cooling coil The added pressure drop imposed by the evaporative cooling coils increases the static pressure requirement for the supply fan to 4 in wg At the chilled water plant a watercooled centrifugal chiller supplies cold water to the conventional cooling coil The cooling tower furnishes water to the indirect evaporative cooling coil A pump rated for 40 ft of static head provides water from an auxiliary source to the direct evaporative cooling coll Note Do not confuse evaporative cooling modeled here with evaporative precooling refer to Evaporative precooling of condenser air on page 3 54 Evaporative cooling reduces the CDS PRMOO01 EN TRACE 700 User s Manual System Design Options 4 41 Direct and indirect evaporative cooling amount of mechanical cooling required while evaporative precooling provides ambient relief for cooling equipment with air cooled condensers on Evaporative cooling and Evaporative cooling extends the operating range of the economizer The outdoor condition at which the airside economizing are dampers are fully open is therefore higher than normal modeled as options of the air distribution system After W Create Systems Options x selecting an airside system uaa in this case Series Fan Sytem description System 001 Soins Far Powesed VAN ds
445. ouling 20 cimiperon Heating 20 cipe ron z 1 No infiltration has been input on the Airflows tab of Create Rooms Infiltration is air from outside the building that leaks into the room often adding to the heating requirement 2 No VAV minimum airflow has been input for VAV systems This can result in no or minimal airflow being supplied to the space in heating mode CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 41 No or low heating energy consumption Example 4 W Create Systems Design Temperatures Akama 1 Sytem desorption JATU Fma m ihig dat Tirana gt Dine Aindnerd Qichumebhsaion Mathes foyin irra ory Coding supe Max 55 F Type Hore Min F Miscou rote pelalren Parre Man cooling ood manmmum biaia leaning F Leaving cooing ced Mar F Eaha sila E HM A AAE a F during dehumidiic ation of edd coll mode m Variable Fan Speed lor capacity control System Faeubyion onip Mo 5 F Humba of lan speeds Hors Mn ss T 1 Pecani antl olkow speed f y Prvcend aiko at medium speed E O Humides Desg hnidy into diene grains Mireur roam balara hurrah 1 The heating supply air temperature has been input at an unrealistically low temperature The capacity of the heating coil is calculated based on the airflow through the coil and the temperature difference across the coil If coil capacity is underestimated the energy consumed by the coil will also be un
446. ow E calculated minimum outdoor airflow set point E critical space A ventilation reset strategy that dynamically solves Equation 6 1 and regulates outdoor airflow accordingly helps ensure that 5 14 System Control Strategies TRACE 700 User s Manual e CDS PRMOO01 EN Ventilation reset for VAV systems every zone is properly ventilated at all load conditions Implementing such a strategy requires m DDC VAV terminals that continuously measure the volume of supply air and the ventilation fraction for each space m A building automation system BAS that continuously monitors this information and dynamically solves Equation 6 1 to determine the amount of outdoor air needed at the air handler m n air handler that continuously monitors the amount of outdoor air entering the system and resets the position of the outdoor return air damper accordingly to maintain the set point calculated by the BAS When effectively applied ventilation reset can also prevent costly overventilation Application considerations E Ventilation reset is most effective if each VAV terminal senses and controls supply airflow independently from fluctuations in duct pressure E A building automation system that monitors and logs the operation of the ventilation system can provide a useful record of compliance with ANSI ASHRAE 62 Related reading E Ventilation and Fan Pressure Optimization for VAV Systems Engineering Bulletin Trane literature number SYS EB 2
447. ow the building to drift during unoccupied hours When the building becomes occupied the design coil capacity may not be large enough to condition the space s to the desired setpoint in a single hour thus triggering unmet load hours Applying this control strategy allows the building automation system to condition the spaces in advance in order to reach the desired setpoint when the building becomes occupied ASHRAE Standard 90 1 2004 and 2007 require optimum start controls to be modeled for systems larger than 10 000 cfm It is recommended that users select the Available 100 schedule for the optimum start schedule Doing so will allow the program to activate the system as early as is necessary to maintain space control if possible under pull up or pull down situations 6 104 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Modeling for LEED Note Only an optimum start schedule is needed to combat unmet hours not an optimum stop schedule Step 3 Additional considerations If the preceding strategies did not resolve your unmet load hours issue investigate the following items m Verify envelope parameters walls floors roots etc are correctly defined TRACE considers the thermal mass effects of the building s envelope Typically loads in a high mass building will peak later and at a lower value than loads in a low mass building Incorrectly defining envelope parameters will have an im
448. owever large rooms and or zones can still cause problems For constant volume systems modeled using one large room a single time of peak is assumed In a constant volume system a sum of the peaks methodology must be used to properly size the equipment If one of the spaces has a different time of peak than the others the system will be undersized when a one room and or one zone model is used In the example shown above the Office East would peak in the morning and the Office West would peak in the afternoon If a single time of peak is assumed the maximum airflow for at least one of the rooms and the system serving It would be undersized Modeling this example as one large room can cause an underestimation of the capacity of the system by as much as 30 to 40 percent For variable volume systems modeled using one large room a single time ot peak is also assumed In a variable volume system a block methodology must be used to properly size the system Modeling this example as one large room may allow the program to calculate a reasonable estimate for the size of the system provided that all of the spaces are occupied and operated similarly However determining precise airflows to the individual rooms and or zones is not possible when a single room Is used Note For additional information related to the sum of the peaks and block sizing methodologies refer to the topic Block vs Sum of Peaks in TRACE 700 Help 6 46 Advanced Usag
449. p Pome ls Chiles 1 elec contrbupal chiu unay chiller untey Chile 2 dioctfrod absorption Aaccoed Ancoded Waterco Waterco Heating plants n llas Heating plare 002 6 m W ster Boder Elecur Gsrfred touca he fecntance hes exc ant pes et Sequencing Cine 5 Chake 1 jebes cedri Thales 2 edna toned abies Chie 2 jieshi shan Chia 1 aer ceniu IEE Re Hki t Click in a cell to display the list of choices ve Utity Minc Accessory Hobe Ender bapan chiens ant feel bo Les ordi Th Rrit cites ret ell Be ued If you choose gt or gt as the operator define the smallest load based control point first Make each successive control point larger than or greater than equal to the one that preceded it If you choose lt or lt as the operator define the largest load based control point first Make each successive control point smaller or less than equal to the one that preceded it TRACE 700 User s Manual e CDS PRMOO01 EN Switchover control for chiller plants lly To create a switchover sequence based on the dry bulb temperature of outside air OADB 1 Select the cooling plant and open the Sequencing dialog box 2 Create two start sequences one that starts the centrifugal chiller first and one that starts the absorption chiller first 3 Pick outdoor air temp as the basis for switching between sequences 4 Using the operator op
450. p type by specifying the Fistcodatpe fine SSS cat temperature of the loop et u entering the building in the e Controt 4 TLoop Ent Bldg field See ee Se Chilled Note IGSHPA should ony be w we used for horizontal borefields West Mayami wet ub o aie Vertical bore requires a Load shack Cogeneeationtee le 1O enfas lions separate IDF file to be usedin Sscentiy dina pine o TETE z conjunction with the project andl He g The Custom selection in this a ne RERE C a field requires a separate a amis am jia a eer M Geothermal schedule defined in the Schedules Library When using either IGSHPA or Oooo men Conca Equipment tag Eade 001 Custom geothermal loop 0 types plant or equipment Fammettipe GerFeedHawomBoe JQ sl En level thermal storage should Thermal storage be defined to reflect th e j e aelinea to retiec e AEDE s Penei c lh oy capacity of the borefield loop Schodde io 11Enter the geothermal loop Hot waia pump Tye ESI Horg min cpm E Equipment schedule avointa ons flow rate geothermal loop mad a ia Demand intro pump type and associated 13 full load energy rate Note The minimum operating condenser temperature of Enter fully mixed as the flow scheme 120n the Heating Equipment tab pick the boiler that most closely matches the anticipated performance 13Enter the full load consumption of the pump that circulates hot water fr
451. pacity based on changing temperatures Note The full load energy rate has to be determined at the temperature of the design condenser temperature or the amount of ambient relief applied will be incorrect Q For water or ground source heat pumps how does TRACE 700 change the hourly compressorenergy consumption Does the calculation change based on the heat pump providing cooling or heating A For GSHP systems TRACE 700 accounts for changes in the mean ground temperature based on IGSHPA International Ground Source Heat Pump Association derived equations The combination of the mean ground temperature and the loads seen by the equipment during the current hour determine the actual waterloop temperature The difference between the actual condenser entering water temperature and the design entering water temperature yields a sink temperature difference In cooling mode the energy consumption of the compressor is then calculated based on the entered design Cooling Energy Rate the load seen by the compressor paired with the compressor Unloading curve and the heat sink temperature difference paired with the ambient modification curve Watersource heat pump calculations are done similarly except that the ground temperature is not factored into the calculation In heating mode TRACE 700 uses the heat recovery energy rate the design energy consumption of the compressor in heating mode the secondary unloading curve and the ambient relief
452. pact on the program s ability to accurately calculate the thermal mass effects of the building If you choose to create custom elements e g walls roots floors be sure to correctly define the library value Remember construction types should always begin with outside inside surface resistance and end with the opposite outside inside surface resistance m Verity correct application of ASHRAE Standard 62 1 in TRACE When modeling ASHRAE Standard 62 1 in TRACE ensure the feature is activated on both the Create Rooms Airflows tab and Create Systems Selection tab Advanced button Doing so ensures an accurate ventilation load calculation See ASHRAE Standard 62 1 on page 4 91 for more information m Utilize an appropriate ventilation schedule Users often wish to schedule ventilation to follow the occupancy schedule The concept is sound but incorrectly modeling this causes problems The standard occupancy schedules in TRACE do not work well for ventilation Since ASHRAE recommends not taking credit for internal heat gains standard occupancy schedules in TRACE set the heating design schedule values to 0 percent When used as a ventilation schedule the O percent value for heating design exempts ventilation from the heating design calculation Instead a more conservative approach would be to utilize a standard TRACE ventilation schedule If you view the standard ventilation schedule with its corresponding standard occupancy schedu
453. pe Reduced yoo C Fulyew i eee i temperature is less than 50 F There are a variety of sensors operators and reset values available In addition and statements and offset values can be used to add more complexity to the reset and lockout controls Reset and lockout controls can be applied to the following schedule entries Schedules used for items not specified will ignore these entries Ventilation Infiltration VAV minimum Main cooling fan Main heating fan Auxiliary fan Room exhaust Main cooling coil Direct evaporative cooling Indirect evaporative cooling Auxiliary cooling coil Optional ventilation cooling coil Main heating coil Advanced Usage and General Modeling Tips Creating schedules Preheat coil Reheat coil Humidification coil Auxiliary heating coil Optional ventilation heating coil System exhaust air heat recovery coil Room exhaust air heat recovery coll Supply air reset Discriminator Economizer Nighttime OA purge Optimum start Optimum stop Duty cycling TRACE 700 User s Manual e CDS PRMOO1 EN Creating equipment and unloading curves The compressor full load energy rate and unloading curve at constant condenser temperature need to be obtained from a selection program sales representative or other source The following example was obtained from the Trane Official Product Selection Software TOPSS For added detail an ambient relief curve should be generated from the cons
454. pply air dew point setpoint then reheat it to the current supply air dry bulb setpoint m When the outdoor dew point is less than the cooling supply air dew point setpoint and the outdoor dry bulb temperature is greater than the current supply air dry bulb setpoint the dedicated outdoorair unit will cool the entering outdoor air to the current supply air dry bulb setpoint m When the outdoor dew point is less than the cooling supply air dew point setpoint and the outdoor dry bulb temperature Is less than the current supply air dry bulb setpoint the dedicated outdoorair unit will heat the entering outdoor air to the current supply air dry bulb setpoint This example will cover how to model the airdistribution system steps 1 8 model the cooling and heating equipment steps 9 11 and assign the loads from the coils to the equipment step 12 4 62 System Design Options TRACE 700 User s Manual e CDS PRMO01 EN Dedicated outdoorair systems Syitem description Fan Cod and DOAU FanCol 1 Start by selecting Fan Coil as the system type Loratart Volume Meany Heater Ordy Induchon Underfloor Aa Divtrituzion 2 On the Dedicated OA tab select the type of dedicated ventilation unit to be modeled In this example the dedicated None no dedicated ventilation unit Corina moh ar dy bu Cool heat a dedicated ventilation unit is cooing sxe at dew cont used to cool the outdoor air to t
455. ption calculated by TRACE 700 during the energy analysis simulation In order for the Visualizer to be available to be selected the first three sections design system and energy must be calculated for the file 1 After the file has been calculated completely go to View Results click the Analysis Reports tab and click Profiles and Energy Consumption 2 After clicking Profiles and Energy Consumption the TRACE 700 Visualizer should open Lert ig A pCi Pres Note If Visualizer opens but no data appears click Open on the File menu click the trc file to be viewed and click Open 6 122 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Creating spreadsheets and tables from calculation results TRACE 700 Visualizer 3 To view one of the standard charts or tables click the desired graph on the list in the bottom left hand corner and click Draw 4 To create a custom graph or chart click Settings at the bottom of the screen or click Settings on the View menu a From the Data Type section choose to view either consumption overall monthly numbers or demand hourby hour numbers and the general component category that you want to view b From the Time of Year section select the months days hours and day types that should be included in the graph c From the Alternative Selection section choose which alternatives to include d From the Display Options sec
456. pum vanabie vorme ii Fu lod energy 0 057 Kwiat wg orit wy 1 Cosy ino 1 Energy type fe Electricty 5 f Delete Control type Mih ega o Mih ega o Miscellanea Accessories Ue a IE a lo Categery a ahhg cine f eee Vind Concerns wider Pump Equipment ipype Cind water pump vat wal Variable Vel Condenser Water Pump Cancel ape i Comments Dirsierba wher puma vrais p on 7 energy 0 000339 ew tore f i Ja i 2 ie en Note While this example l Eremhee Emi z 70 illustrates a system with a onta ypa th epaper variable volume condenser water pump a constant volume condenser water pump is a more common Uniesding curve E Tower oren application awo of Full Power ED Coning het Par Dardiga Fiat Coning Toae 15 F T Coning oem vat VED Optional Tow k Camement airi bowed yalh g iuiar C sling Tomar eth VFD Ba eee on Egri Low speed en Capacity 100 Percent Condernarype Eorna pE 5 Munberofests fr Fwa Optional Two Speed Tower Fans Daal at e TAA the design o rate to 6 y gom ton where y 10 F new au x 3 gom ton r Deign Cherie Temperstuve Approach m F Flange js F D wane P Ansigrmeri of Ced Loshi FF Man FF reine rapon F Optional verdilation T Dee evap Fe Anoop Fe irie cotin kumi alx conumed ss Cooling T th VFD MAM inact AD power pn cooling Tower wi e
457. pump rme a a heating E q load i N evap cooling load The following procedure demonstrates how to implement the cooling plants pumps geothermal loop and heating equipment CDS PRMOO1 EN TRACE 700 User s Manual Cooling and Heating Plants 3 77 Central geothermal chillers Define the cooling plant by selecting Create Plants in the Project Navigator window 1 Drag two water cooled chillers to the cooling plant and click the Cooling Equipment tab For each chiller 2 Select the appropriate equipment type 3 Pick Parallel as the sequencing type 4 Enter the cooling capacity 200 tons 5 Enter the cooling capacity for the chiller when it is in heat recovery mode 1870 Mbh 6 Specify the full load energy consumption for the chiller in the cooling mode and in the heat recovery mode 7 Enter the pump types and full load energy consumption rates for the chilled water pump and condenser water pump If there is no heat rejection device there would be no condenser water pump The bidirectional cascade pumps for the evaporator and condenser energy transfer loops will be entered as miscellaneous accessories in a later step as will a secondary distribution pump and a borefield pump 8 Click Controls 3 78 Note The two chillers are identical As an alternative drag only one water cooled chiller to the cooling plant follow steps 2 through 14 a and then click Copy Equip to crea
458. quire less chiller capacity The savings that result from selecting a smaller chiller may partially offset the additional first cost of thermal energy storage m Many utilities offer negotiable rebates for thermal storage Contact your local utility representative to maximize the potential economic benefits Related reading E hermal Storage Engineered Systems Clinics Trane literature numbers ISS CLC 1 ISS CLC 2 ISS CLC 3 and ISS CLC 4 E Control of Ice Storage Systems Applications Engineering Manual Trane literature number ICS AIM 4 E ce Storage Systems Applications Engineering Manual Trane literature number SYS AM 10 Sample scenario There are various ways to design a chilled water plant with thermal energy storage This section demonstrates how to model two variations E lhermal energy storage with one chiller page 3 22 m Thermal energy storage with multiple chillers page 3 25 Note TRACE 700 generates a special report Thermal Storage for HVAC designs that include thermal storage The report provides an hourly profile of ambient conditions and plant level cooling loads as well as chiller loads chiller energy consumption and available storage capacities available for cold storage applications ice and chilled water Thermal energy storage with one chiller A 500 ton centrifugal chiller makes chilled water and ice 335 tons at energy rates of 0 65 kW ton and 0 78 kW ton respectively The ice storage tanks
459. r It is also recommended to change the Equipment Tag to a more appropriate name 6 Because pumping energy is required in this scenario input the pump type and the full load energy rate CDS PRMOO01 EN TRACE 700 User s Manual Coolerg plants Mas Paachaced Cred weer S BY Watercooled chiles 001 Cooling tower Condense water puno Primary chilled water pure Heating plants Mes Heating Plat 002 Aectcoed Arcod Waterco Waterco chiller urtay chiller utey so HA Elect Garfred oouace he resutance heat enc se Arcod condenser Equpmert category water cooled chas Equpmerttype Detak water cooled cher v Thamal storage Purchaved Chiled Water Heat reyecton Eqiomerttag Pew 15 Tye Nove z Equpmert categoy Waa cooled chas Hourly ambient wet bub citset Pischsied Ched waer D hemmed storage Sequencing ype Serge Type None Note The COP of purchased chilled water should be 1 0 or less A COP of 1 indicates that for every Btu of cooling load 1 Btu of purchased chilled water should be consumed Refer to Frequently asked questions which begins on page 6 20 for additional details Cooling and Heating Plants Purchased chilled water fw ater cooked chiler 007 Type Contri tovver fot Cort Chillers x Hourly ambient wet bulb offret 3 39 3 40 Purchased district steam and purchased district hot water Purchased distr
460. r that asks whether the user wants to account for energy recovery transfer during the design and energy analysis simulations or only during the energy analysis simulation Select Yes for this example 3 Select the appropriate supply side deck for the device For this example Return outdoor air downstream will be selected as the supply side deck This will allow the heat exchanger to reheat the supply air after it has left the cooling coil 4 Select the exhaust side deck for the device In this case Return air will be selected as the exhaust side deck This will allow the heat exchanger to use energy from the return air stream to provide reheat Note If the proper airstreams are not selected for supply side and exhaust side decks of the energy recovery transfer device then the unit will not function correctly or may not function at all Note If two energy recovery transfer devices are input and both stage 1 and stage 2 devices are given the same exhaust side deck then stage 1 will be upstream of stage 2 4 24 System Design Options Fixed plate heat exchanger TRACE P00 Salles bring macowargAransfar Wt diniga ip curranthy harrad off on the Charpa Lewd Par iaeia caren tiaki row Woe bo hurni il en Direct efficiency f x Dect cod echeckie hie 1 pooo Indeect alicancy Indeect cod schedule vile 1 Stage Artai Energy Recoverpy Transter Type Fined plate HX parallel SA tar
461. r W Create Rooms Single Worksheet er Pooyect Informator BW Econcerecs MT Akemaive U Uy Rates t Lie Cycle Coats A Enagy Mgt amp Sytema rones and mona E Classroom 101 FB csesoom 102 Classroom 103 G Clettroom 104 4 BE Room 100 Adeninittration BB Room 110 Tech Stop H Eg Room 111 Muti Room So hitos amp Paope t Liping Project Tree view CDS PRM001 EN TRACE 700 User s Manual Program Overview 2 13 Performing basic tasks ot Create systems Adding an airdistribution system to a project is a matter of choosing a system type A majority of the information needed to calculate coil loads and airflows is automatically provided based on the system type you select However system and building specific values such as fan static pressure fan motor location and so forth should be defined If you wish you can limit the range of design supply air temperatures or specify a minimum humidity level You can also add options such as dedicated outdoorair systems evaporative cooling exhaust air energy recovery economizing and dehumidification controls Review the system defaults to verify that they are relevant to your specific project analysis Unless you are modeling an existing airdistribution system It is seldom necessary to edit the default values for coils Figure 2 10 Create systems FG Room 110 Tech Shop E Room 111 Minic Room E Caterers E Gymnasium ES Cl
462. r appear in the calculation results because TRACE 700 will try to add in the cost 2015 years from the start of the study For accurate results the user should enter the number of years after the start of the study that the cost is incurred rather than the actual date Energy Only Version m Verify that the most current version of the program is installed To determine what version of the program is Installed click About TRACE 700 on the Help menu The most current version can be reached by clicking Help then clicking Trane on the Web and finally clicking Check for updates When you have downloaded the update assuming that an update with a higher version number exists you need to double click the executable patch to apply it Please ensure that TRACE 700 is closed during the update process and click Yes to Exporting and Importing Custom Library Members Load Design and Energy CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 19 Common modeling mistakes Frequently asked questions This section contains some frequently asked questions regarding TRACE 700 Additional questions and answers can be found in the online C D S Software Knowledge Base found on www tranecds com Q How does TRACE 700 determine cooling supply airflow and temperature A TRACE 700 performs an iterative psychrometric analysis to determine cooling supply air temperatures and solves the sensible heat equation to determine s
463. rage The report provides an hourly profile of ambient conditions and plant level cooling loads as well as heat pump loads heat pump energy consumption and condenserloop temperatures for hot and cold storage applications The following procedure demonstrates how to model the air distribution cooling and heating functions of the GSHP system and assign the coil loads CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 73 Ground source heat pump system on To model an applied GSHP system begin by defining air distribution 1 Pick Water Source Heat Pump as the system type Then click Apply to save your entries On the Fans tab select Hydronic in heat pump fan and enter 0 5 for the static pressure llay Next describe the cooling and heating plants represented by the GSHP system and backup boiler 3 Drag the appropriate icons 3 74 from the Equipment Category section to define each plant Rename the cooling plant as Ground source heat pump and the heating plant as Backup boiler Select the cooling plant and click the Cooling Equipment tab Choose the ground source heat pump that best matches the target performance Enter the full load consumption of the pump that serves the common water loopo the primary chilled water pump in this case Select the backup heat source and select the ground loop for reject condenser heat Click Controls Cooling and Heating Plants Al
464. rates from 6 a m until 6 p m Perera t Sythe Seheriion Eppa MAK Epse VAV vaih Aahas SCS Wir Fk Cee elt pres Wa pire WAM wath Load Hizal Fisa Fan Purser WO Hig Cod ori Hiera Dia Duba Parsia Fan oveened WAV CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 3 Desiccant dehumidification 4 4 2 Specify the type of air to air energy recovery transfer and the location of the process air stream This example uses a solid desiccant located on the ventilation deck A message will appear that asks whether the user wants to account for energy recovery transfer during the design and energy analysis simulations or only during the energy analysis simulation Select Yes for this example Select the appropriate supply side deck for the device For this example Ventilation upstream will be selected as the supply side deck The desiccant device will be used to dehumidify the outdoor air stream Indeect ethcatrcy Indeect col schedule Stage Aatodas Energy Recover ranster Type Sobd desc on vent deck Abemanve 1 System description System 001 desiccant device for design and energy Evaporative Cooling R 5 i analysis Click No to ignore the desiccant ye None Direct efficiency fi Desci cod echeckie t Click Yes to activate or include the device during the design calculation and include it only during the energy analysis
465. re Cycling each chiller pump pair can significantly reduce the total system flow and may cause insufficient cooling in some areas of the building m The load profile for a plant with multiple chillers differs trom the load profile of each chiller due to thermal inertia Judiciously sizing the chillers can improve the overall efficiency of the plant Related reading E Chilled Water Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRCO16 EN E Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN m Chilled VWater Plants and Asymmetry as a Basis of Design Engineers Newsletter volume 28 number 4 Modeling instructions The procedure for modeling a cooling plant with chillers piped in parallel is similar to the procedure for a decoupled chiller arrangement refer to Decoupled chiller arrangement on page 3 3 When defining the cooling plant however choose Parallel as the sequencing type for each chiller and do not include a secondary distribution pump W ereate Plants For each chiller choose the sequencing type that describes the hydraulic arrangement of the E 5001 Cryst vol chal waster pumo PAID Crt vol cred wale penn 3 8 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMOO01 EN Parallel chiller arrangement Series chiller arrangement Piping chillers in series means that the e
466. re in the controlled space drifts more than 3 F from the set point or if the relative humidity exceeds the design target by more than 10 percent E Schechile Library Schedule type Utization Detenptinn eam 06pm 1 5 Simson ype Reduced pear C Ful yeu Comments January December Sahada to Sunday Heating deagn NOTE The reset aed lockouts are awedoble for the feliwang Desy phase efiliabon venison reheat mrar ard al system Schedule Abematve 1 System description System 001 Single Zone Fan cycling schedule nto lan cycing Gam tobpom mng Avollatie 100 kiw Cim Available 100 kiw Cim lav okste 100 kw Cim Avaliable 100 kw Cim Avelsble 100 Kw Avelsble 100 TRACE 700 User s Manual e CDS PRMOO01 EN 3 Use the Library Template ay as Editors program to create a o T T custom duty cycling i F 3 m por oe oea schedule The Duty a Shin nar enone z 5 New Sched Cycling schedule describes nam EEE when this control strategy Janan December Sanday 1o Sunday AE aoe Click in a cell to display Men Defeaion on weekdays from 6 a m Dal Oetnitien Cogy Definition the list of choices until 6 p m The schedule also establishes criteria that E prevent duty cycling if it impairs thermal comfort and lockout table Room ay bulb temperature E Cooking themmorts set port Room dy bud bempeeatiuse lt Hasira amoda cel port 3 F NOTE The reset arxi lockouts one awadable
467. refer to steps 1 through 6 in Sensible wheel on page 4 34 m for nset B refer to steps 1 through 6 in Total energy enthalpy wheel on page 4 15 E for nset C refer to steps 2 through 7 in Coil loop for exhaust air energy recovery on page 4 8 Related reading m Airto Air Energy Recovery Engineers Newsletter volume 29 number 5 E Airto Air Energy Recovery in HVAC Systems Applications Engineering Manual Trane literature number SYS APMO003 EN Sample scenario To input the type of heat recovery in Figure 4 10 Inset C we will model a restaurant that is cooled by a constant volume rooftop A heat pipe will be used to precool the mixed air before it enters the main cooling coil and reheat the air after it leaves the main cooling coil This arrangement is sometimes referred to as series energy recovery he series arrangement will reduce both the cooling energy and the reheat energy required by the system if it is a system with reheat while increasing dehumiditication capabilities CDS PRMOO01 EN TRACE 700 User s Manual System Design Options 4 29 Heat pipe To model the heat pipe scenario 1 After defining the system select the desired airto air energy recovery transfer type which determines the type of energy recovery transfer and the basic configuration In this case Heat pipe series SA tempering 2 Amessage will appear that asks whether the user wants to account for energy recove
468. report System Design Options 4 5 Desiccant dehumidification 6 Choose the schedule that describes when the desiccant device is permitted to operate For this example a custom schedule was created that allows the desiccant device to operate only from 6 a m to 6 p m Now that the desiccant subsystem has been input the coil loop needs to be added as the second stage of energy recovery The coil loop will preheat the regeneration airstream reducing the amount of energy required to regenerate the desiccant and cool the outdoor air after it leaves the desiccant device therefore reducing the amount of cooling energy required Refer to Coil loop for exhaust air energy recovery on page 4 8 for step by step instructions on how to input a coil loop Abemative 1 System description System 001 Evapcestive Cooling Type None Deecteeny Soona Dereci cod schade E35 6pm y indvecteticeney D Onk Indrect col schede 53m 06pm Stage Altona Energy Recowerp Transter Stage 2 Aintowka Enengy RecowenT ranater Type Scbd detic on vent deck Type Nore detoa Sup tide deck Vernianon upvrear Supada deck entiation upsuex J Eride dack System ehas G Sthedue wam gt Seems F arrPoweed VAV The default schedule Available 100 wvill allow the energy recovery transfer device to operate yearround Liquid desiccant systems should typically only be made available to operate during occupied hours
469. ribute to the heat transfer characteristics of the room Walls and roofs describe surfaces including windows that are exposed to the outdoors Partitions are interior dividers that separate spaces with significantly different temperatures In addition to walls roofs and partitions a room description includes other factors that affect cooling and heating loads CDS PRMOO01 EN TRACE 700 User s Manual A Brief Introduction 1 5 About TRACE 700 1 6 A Brief Introduction About TRACE 700 internal loads people lights and heat generating equipment infiltration and ventilation requirements Zones divide a building into separately controlled areas Each zone consists of one or more rooms that share similar heating and cooling requirements In a variable airvolume VAV system for example a VAV terminal typically serves several rooms If you model these rooms as a zone TRACE 700 will calculate the design capacity of the heating coil in the VAV terminal as well as the design airflow for each room Systems and plants In the TRACE 700 vernacular system describes the distribution of air to and from the conditioned spaces in the building TRACE 700 can model more than 30 types of systems in five categories variable volume constant volume mixing constant volume non mixing heating only and induction Each system type in TRACE 700 broadly describes the airside components coils fans and air paths and the method used to size
470. rigerant inside the evaporator evaporates as It absorbs heat from the warm air Given the comparative coolness of the air flowing over the condenser the refrigerant vapor pressure is lower in that section of the heat pipe than in the evaporator The difference in vapor pressures causes the refrigerant vapor to migrate trom the evaporator to the condenser Cool air flowing over the condenser absorbs heat from the refrigerant vapor causing the refrigerant to condense The liquid refrigerant then wicks back to the evaporator section of the heat pipe and the cycle repeats The direction of heat transfer reverses when the relative temperatures of the two air streams are reversed In an outdoor air preconditioning application for example when the outdoor air is warmer than the exhaust air the evaporator is in the outdoor air stream and the condenser is in the exhaust air stream When the outdoor air is cooler than the exhaust air the evaporator is in the exhaust air stream and the condenser is in the outdoor air stream Figure 4 10 and Figure 4 11 on page 4 28 show the typical arrangements for sensible heat recovery in mixed air and dedicated ventilation systems In Figure 4 10 which shows mixed air systems sensible heat recovery can be used to reheat the dehumiditied supply air Insets A and C or to precondition the outdoor air Insets B and C CDS PRMOO01 EN TRACE 700 User s Manual System Design Options 4 27 Heat pipe Figure 4
471. rio The airdistribution system for a building includes a total energy wheel also commonly referred to as an enthalpy wheel The wheel preconditions the outdoor air entering the building by exchanging both sensible and latent heat with the main exhaust air stream When operating in the heating mode the wheel warms and humidities the outdoor air During the cooling mode it cools and dehumidities CDS PRMOO01 EN TRACE 700 User s Manual System Design Options 4 17 Total energy enthalpy wheel 4 18 To model the total energy wheel scenario 1 After defining the airside system select the desired air to air energy recovery transfer type which determines the type of energy recovery transfer and the basic configuration In this case Total energy wheel OA preconditioner A message will appear that asks whether the user wants to account for energy recovery transfer during the design and energy analysis simulations or only during the energy analysis simulation Select Yes in this example Select the appropriate supply side deck for the device For this example Ventilation upstream will be selected as the supply side deck The total energy wheel will be used to condition the ventilation air upstream of the optional ventilation coll System Design Options Total energy enthalpy wheel TRACE PDO i Ahemaive 1 System description System 001 Stage 1 Airtodie Energy Recover Transier Tcxaleneeg
472. rom the simulation 8 Be sure to apply your changes On the Heating Equipment tab pick the boiler that most closely matches the anticipated performance 9 Enter the full load consumption of the pump that circulates hot water from the boiler Note The minimum operating condenser temperature of the selected heat pump refer to page 3 67 determines when the boiler turns on to maintain the condenser water temperature To view or alter this entry use the Library Template Editors program 10 Finally assign each coil load to the appropriate plant Cooling Cquipereent Controls Plant descioton Wie Diuca Meat Pung Eqqapmerd Lay afster souls heat pump Fees Cooling Type Hone Pump hilload enegy J i Mite Pala vaalia pete fo F Load rheddrg economize Ho Faje condens has Hewngpae 8 8 Fejet heat to plant Eocku ae Equipment schedule vala a Demand kating pisiy T Hot gar reheat Iga Ne z Abomstive 1 Herga Brko o Egieta Bae 0 YS Equipment catego Da N Equmertiype Gas Fred Ha Wate Boie 8 ota 7 fs 3 Peccere efficient Capacty Eneo rate fe qsaco Heaters water coc pump Ful load a a Alleerisiren T Unassigned Sytner odi E Man Heating Col CDS PRMOO01 EN TRACE 700 User s Manual This entry identities the heating plant that will serve cannot satisfy the load Equement schedule Avvendatile 100 Demand iming zz poety BHi Waa paps
473. rooms page 6 47 Oversizing and undersizing page 6 51 Balancing airflows page 6 60 Selecting a DX unit using TRACE 700 output page 6 68 Selecting a chilled water cooling coil using TRACE 700 output page 6 74 Modeling tor LEED page 6 80 Input tips Quick building inputs via the New File Wizard page 6 110 Using TRACE 700 ChillerPlant Analyzer page 6 114 Inputting an existing load profile page 6 118 Creating spreadsheets and tables from calculation results TRACE 700 Visualizer page 6 122 Using templates page 6 125 Creating alternatives page 6 131 Creating schedules page 6 137 Creating equipment and unloading curves page 6 143 Creating utility rates page 6 150 Adding weather locations and activating the 8760 calculation methodology page 6 167 CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 1 m Altering a load design file for energy analysis page 6 170 Advanced usage m Archiving and un archiving instructions storing library members with project files page 6 175 Printing used library members page 6 176 Combining files page 6 177 Creating a new file based on an existing file page 6 179 How to sort output page 6 180 goXML import and export page 6 181 Importing a load design Version 3 x or Version 2 x file page 6 189 6 2 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Common modeling mistakes This section describes m
474. rs may access this feature through Calculate and View Results by selecting the Rotate and Average PRM Results checkbox As with the fan sizing feature TRACE applies the automatic rotation to the alternative designated in the drop down menu for the Performance Rating Method Note Calculation time will increase significantly when this option is chosen because the simulation must run for each direction 6 100 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Modeling for LEED Calculate and iew Results x Alternative 1 Alternative 2 Results Exist F Results Exist SNEER 09 02 10 03 26 PM Cee IRCA a al Results Exist Results Exist Select All 09 02 10 03 26 PM 09 02 10 03 26 PM Results Exist Results Exist Clear All saa 7 re PM sa ern a PM Economics esults Exist esults Exist Load Param Economics 09 02 10 03 26 PM 09 02 10 03 26 PM z 3 Aa Energy Param Alternative 2 Design Calculation Perform special building block calculations during Design execution time will increase View Results Results exist for this calculation It was last calculated 09 02 10 03 26 PM r Base Alternative For Template data has been modified Economic comparison To be calculated x cose Room data has been modified System data has been modified Energy cost budget None X Performance rating JAltemative 2 v method IV Rotate and average PRM results
475. rs of cooling load using this chiller plant could be estimated as 410 kWh x 0 05 per kWh 20 50 if no demand charge customer charge and so on exists in the utility rate structure Assuming that we own the chiller plant and want to sell chilled water to a neighboring building the price for the purchased chilled water PCVV would be determined as follows 1 therm 100 000 Btu _ 6 000 000 Btu _ 60 therms of cooling 100 000 Btu therm From above it costs 20 50 to produce the 60 therms 500 ton hours of cooling This would yield a cost of 20 50 0 34 per therm 60 therms p The charge to the neighboring building for the purchased chilled water in this scenario would be 0 34 per therm plus a profit margin In this scenario we will use a profit margin of 0 11 per therm The cost of using the PCW to meet the 500 ton hours of cooling load would be Cost of PCW 60 therms x 0 34 per therm 0 11 per therm 27 00 CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 33 Frequently asked questions Example 2 Purchased Chilled Water COP To calculate the COP of the purchased chilled water PCVV that is used to provide 500 tons of cooling for one hour the following calculations would be used COP of PCW Cooling provided Energy used to provide cooling Cooling provided 500 ton hours x 12 000 Btu hr ton 6 000 000 Btu Energy used to provide cooling 500 ton hours of
476. rsource heat pump VVSHP system and a dedicated outdoorair unit that delivers conditioned outdoor air to the individual heat pumps During the cooling season the dedicated outdoorair unit dehumidities the outdoor air to 55 F dew point and then reheats It to a neutral 70 F dry bulb During the heating season the dedicated unit heats the outdoor air to 68 F dry bulb m VVhen the outdoor dew point is greater than the cooling supply air dew point setpoint the dedicated outdoorair unit will dehumidity the entering outdoor air to the cooling supply air dew point setpoint then reheat it to the cooling supply air dry bulb setpoint m When the outdoor dew point is less than the cooling supply air dew point setpoint and the outdoor dry bulb temperature is greater than the cooling supply air dry bulb setpoint the dedicated outdoorair unit will cool the entering outdoor air to the cooling supply air dry bulb setpoint m When the outdoor dew point is less than the cooling supply air dew point setpoint and the outdoor dry bulb temperature Is less than the cooling supply air dry bulb setpoint the dedicated outdoorair unit will heat the entering outdoor air to the heating supply air dry bulb setpoint This example will cover how to model the airdistribution system steps 1 8 model the cooling and heating equipment steps 9 11 and assign the loads from the coils to the equipment step 12 CDS PRMOO01 EN TRACE 700 User s Manual System
477. rtugal const vol ns 0 00032 kw Citrrin wg kwim kw Cim kwim KWC Additional Items Avelsbtle 10 Available 100 on Avelsbie 1005 Avelsble 1003 Avelabie 100 Avelsble 100 Avellsble 100 For a system to be 100 percent outdoor air all rooms assigned to the system must be specified as 100 percent outdoor air Ventilation load shown on the output reports will only reflect the cooling required to cool the air from ambient conditions to room neutral The cooling coil will be sized based on the total load cooling the air from ambient conditions to the leaving cooling coll conditions in a 100 percent outdoorair system Ventilation load is calculated based on equations 26 and 27 found on page 26 9 in the 2001 ASHRAE Handbook of Fundamentals System Design Options Systems with 100 outdoor air 4 75 4 76 Cold air distribution System Design Options Cold air distribution Cold air distribution describes comfort cooling applications that deliver supply air of 48 F or less to the occupied spaces in a building Supply air temperatures of 45 F to 48 F are most common but applications with temperatures as cold as 42 F also exist Successful installations throughout this range demonstrate how readily cold air distribution can be adapted to individual job requirements The appeal of cold supply air lies in the dramatic impact on the amount of air required for sensible cooling Lowering the supply air
478. ry transfer during the design and energy analysis simulations or only during the energy analysis simulation Select Yes for this example Note Series energy transfer in mixed air systems typically does not reduce cooling equipment capacity because no energy transfer occurs at the design cooling conditions 3 Select the appropriate supply side deck for the device For this example Return outdoor air downstream will be selected as the supply side deck The heat pipe will be used to reheat the mixed air stream downstream of the main cooling coil 4 30 System Design Options Heat pipe Click Yes to activate energy recovery transfer for design and energy analysis Click No to ignore energy recovery transfer during the design calculation and include it d only during the energy analysis simulation Create Systems Options Abematrve System description Penara Note This message will only appear whenever an energy recovery transfer device is added and Allow energy recovery transfer during design calculations is turned off Stage Artoak Energy RecowerT ranster Type Has ppt iamas SA tampering 1 Type det nal Supande deck Rebun ad on dewratinan Supreme deck ertistion upstres Exdrtade deck Fear adia a upiireae STRACE 700 Kj Schade avai n0 F S Salle egy ricceerstransher al cation i currentty hamad off Chie esl on Upe Charge Liv
479. s Select Create templates for this alternative based on click Alternative 1 on the list and click OK Note The list can also be displayed by clicking Alternatives Setup 4 To input the new templates data display the Templates window s by double clicking the Templates section for Alternative 3 and editing the data Note The Templates window s can also be displayed by clicking Alternative 3 and clicking Templates The appropriate sections of the new alternative need to be changed from Use to Create based on or Create new In this example the Templates section needs to be edited and most of the templates inputs will be identical for the two alternatives As a result Create based on will be used Note Templates cannot be Created New xe TRALE 700 CACDS TRACE 700 Projects Tutorhaltre tre Fle Edt Actions View Options Liwsi Templates Abernutives Setup Window Help leo gt R eoerkeackeve CRE HR J Project Navigator Enter Propa Indommaber Bose Cae A Select Weather Infomation La Corse Wisconsin 3 Cental AHU Glass Siudy La Crosse Wieconsin 11 Temgistes Use Aberaitrve 1 Use Alem Use Aber pis ona goal basii Tork changertorpominat UseAr coveted in lemplates ppu will sho need bo mese arrap Tow bhia aeara Note If Alternative 2 had templates that were created based on Alternative 1 or templates that were created new the Alternatives Setup m
480. s Therefore none will Templster Width an ot be input in the Create Rooms Room Other Anne intemal Otice Aes fot cfa n section This is the reason that the a skylight glass type on the piad sara Wel Construction template could be ae left at the default value eee Pe f FP PI zj CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 129 Using templates Additional items and notes 1 Any changes made to the template s will change the data in all of the rooms that use that template Therefore if the glass type specified in the project changes all that the user needs to do is change the glass type in the Construction template s used by the rooms If no templates were used in the Tile then each wall would need to be manually changed to the new glass type This is one of the ways that templates help save time 2 When a templated value is overridden in Create Rooms the color of the entry changes from red to black It is important to understand this distinction When you reapply or change an existing template only the values in red are affected Entries in black must be changed manually or reverted back to the templated value 3 To go back to an original template value click Template on the list for that parameter or type in and press enter for the numeric fields 4 Do not use any non alophanumeric characters in the names of templates or rooms 5 Create
481. s This schedule should typically only be used for design calculations not for energy analysis It simulates 100 percent of the internal loads in the building 24 hours a day for energy analysis This tends to lead to an overestimation of cooling energy and an underestimation of heating energy Select an internal loads schedule that will provide a realistic load profile for the building Also ensure that the internal loads are not scheduled as Available 100 This schedule should typically not be used for internal loads It simulates 100 percent of the internal loads in the building 24 hours a day which may not be what is actually occurring in the building In addition it also tells the program to take credit for the internal loads during the heating design calculation This tends to lead to an overestimation of cooling energy an underestimation of heating energy and undersizing of the heating coils due to the internal loads meeting all or most of the heating loads If custom schedules are being used for the internal loads be sure to check the accuracy of the inputs for the Weekday Saturday and Sunday day types To view the schedule click Schedules on the Libraries menu and select Utilization as the Schedule type CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 171 Altering a load design file for energy analysis For additional details on schedules please refer to Creating schedules on pa
482. s ae ears definitions can be found below the comments section of Bye CeO DSPE the schedule The definitions tell the program what hours reflect me aye A are on peak off peak mid peak or superoff peak the peak is expected to TEL M a occur For additional details on creating schedules refer to Creating schedules on page 6 137 Also peak and on peak are synonymous in TRACE 700 Note The cooling design CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 159 Creating utility rates 15Now that the weekdays have been defined the weekends must be defined by clicking New Definition Select day types Saturday to Sunday and enter the hours and rate type Click Save and then click Close 16From the Project Navigator screen go to the Define Economics section of the program and select the custom utility rate and the Time of Day schedule that were just created IMPORTANT NOTE Because there is not an off peak rate defined for gas the utilities must be selected individually and no time of day schedule should be selected for gas If this is not done all gas consumption that occurs during hours that are not defined as on peak in the time of day schedule will be free 6 160 Creating utility rates Advanced Usage and General Modeling Tips w Library Template Editors slojx j Fle vee Options window mie TF OVYaxX Sel BOeserivyligbes4 cronrsF7 yee g E Schede
483. s and each succeeding chapter provides basic how to instructions to helo you model common system level HVAC options and control strategies Each example begins with a brief description of the system option or strategy followed by a sample scenario that illustrates the entries needed to mode it Typical values are suggested where appropriate TRACE 700 User s Manual e CDS PRMOO01 EN Decoupled chiller arrangement The basic decoupled chilled water system shown in Figure 3 1 Is sometimes described as a primary secondary pumping arrangement Although separate pumps are dedicated to the production and distribution sides of the system meaning that both pumps transport the same water there Is no duplication of pumping energy That is because the production pumps only overcome the production side pressure drop production piping chillers and check valves while the distribution pump only overcomes the pressure drop on the delivery side of the system distribution piping and coils Figure 3 1 Decoupled chiller arrangement constant flow production pumps chiller chiller ma constant primary flow variable secondary flow system coils 2 way control valves demand gt supply demand lt supply bypass variable flow distribution pump A bypass line hydraulically decouples the production and distribution pumps preventing
484. s m Cooling People m Cooling Miscellaneous Equipment E Cooling Ceiling E Cooling Ventilation E Cooling Oversizing m Total Cooling Heating Skylite Solar Heating Skylite Conduction Heating Roof Conduction Heating Glass Solar Heating Glass Conduction Heating Wall Conduction Heating Partition Heating Exposed Floor Heating Infiltration Heating Lights Heating People CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 187 goXML import and export mM Heating Miscellaneous Equipment E Heating Ceiling E Heating Ventilation m Heating Oversizing E otal Heating m Coil Loads These values come from the System Component Selection report m Main Cooling Coil Tonnage if main cooling coil is at the room level E Auxiliary Cooling Coil Tonnage if auxiliary coil is present in system m Main Heating Coil MBh if main coil is at the room level m Preheat Coil MBh if preheat coil is at the room level m Reheat Coil MBh if reheat coil is at the room level E Humidification Coil MBh if humidification coil is present in system m Auxiliary Heating Coil MBh if auxiliary coil is present in system m Fan Airflow These values come trom the System Component Selection report m Primary Fan if fan is at the room level E Auxiliary Fan if system required m Room Exhaust Fan user specified E Diffuser Additional ttems 1 Each room in CAD must have a unique name and special characters punctuation
485. s VAV system types trom the variable volume category of airside systems TRACE 700 User s Manual e CDS PRMOO01 EN m Jo model the effect of heat recovery on the sizing of cooling and or heating equipment a Click Change Load Parameters in the Actions menu b Select the check box labeled Allow energy recovery transfer at design near the left side of the dialog box Note TRACE 700 automatically asks the user whether this box should be checked when a heat recovery device is selected coana satov res Fattmornth jlerusy 7 Entered factual Cancel Lat month GEES Repomed Actual bd Help Pektou 0 Methodology Coding TET d Buking osartalion O ding roe Nexth Hesing fuato a Wall load to plenum lei ston Vary wath vand ipeed r Ow ortig tecoverinansler at deti Outexte him vay with wand ipeed I Force VAV minimum ahvays gt nominal ventilation Tenan Fiat tenan wih rome colsted obstackes ding design I Fletest design pesk Fest morth Last month Room circulation rate Medium Daylight savings Summer pood gt Select this box to model the effect of airside energy recovery on equipment capacities Equipment capacities calculated to reflect airside energy recovery at design may differ significantly from the capacities calculated without this option Keep this in mind when determining how to size system components CDS PRMOO1 EN e TRACE 700 User s Manual Program Overview 2 27 General mod
486. s and Plants pane Mas Cooling Plant 1 Chiller Plant OT Cools System Dua Pah Ar Handia U Main Cooling Cod Optional Ventilation Cooling Col Ia Heating plant 1 Boder OT Heating System DuabPath Ar Marcie E Main Heating Coa E Optional Vertiation Heating Cod The illustration labeled After shows the completed assignments Table 4 10 Equipment types Cooling Equipment tab Heating Equipment tab Watercooled chiller 3 stage centrifugal gas fired hot water chiller boiler 4 72 System Design Options TRACE 700 User s Manual e CDS PRM001 EN Dual Path Air Handler Split Dehumidification Unit Systems with 100 outdoor air 1 Select a weather file and input the room information room areas thermostat setpoints internal loads and so on as would be done in a typical file systems that use 100 percent outdoor air are common in laboratories and hospitals This system is the only equipment serving the assigned zones Note This system should not be confused with a dedicated outdoor air system or dedicated ventilation unit A dedicated outdoor air system uses a separate air handler to condition the outdoor air before delivering it to the outdoor and or mixead air intakes of other HVAC units or directly to the occupied spaces Terminal units handle only the local space loads associated with the building Sample scenario A hospital has a laboratory area that requires 100 percent outdoor air The air handler will b
487. s due to pull up pull down loads Note The unmet load hours that are displayed in the Building Temperature Profile report are not additive because any one space can trigger an unmet load hour but if multiple spaces have unmet conditions for the same hour then only a single hour is tallied This means that there are a total of 8760 unmet load hours possible for either heating or cooling Step 2 Review inputs Once the problem areas have been identified focus on the data entry process The Sean for Errors feature found through Calculate and View Results reports many of the items discussed below Utilizing this feature particularly prior to calculating will help identify potential errors Keep in mind many 6 102 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Modeling for LEED of the results are simply warnings and do not necessarily require action only your attention to ensure the model was set up as intended m Verity that design and simulation schedule assumptions are accurate Perhaps the single largest area of uncertainty in a building simulation model occurs in the scheduling of internal loads TRACE allows you to differentiate design and simulation internal load schedules for proper coil sizing If the design schedules are too moderate coils could be undersized Alternatively if the simulation schedules are overly conservative this could also lead to undersized coils due to dynami
488. s the primary component of a hybrid cooling plant or in other applications CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 31 Direct fired absorption cooling Il To define the cooling plant 1 Choose a direct fired absorption chiller from the water cooled chiller category as the equipment type 2 Specify the cooling capacity in this case 650 tons 3 Enter the full load consumption for each pump 4 Assign the excess heat from the direct fired generator to the heat rejection equipment To define the heating plant 5 Choose a hot water boiler as the equipment type 6 Enter the full load consumption for the hot water pump 3 32 Cooling and Heating Plants Direct fired absorption cool Assigning excess heat to the heat rejection equipment allows the heating equipment the boiler to satisfy the entire heating load It also tells TRACE 700 to ignore the heat recovery capacity of the chiller where electricity is expensive or in short supply For example use the direct fired absorption chiller to satisfy the peak load and an electric chiller to handle the base load Related reading Absorption Chiller System Design Applications Engineering Manual Trane literature number SYS AM 13 Absorption Water Chillers Air Conditioning Clinic one of the equipment series Trane literature number TRG TRC011 EN Sample scenario A 650 ton direct fired absorption chiller satisfies the cool
489. schematic drawing of the systems in Create Systems can be used to help find the correct system type based on the heating coil location s For these system types zones should be created if one terminal device will serve multiple rooms The same supply fan and cooling coil will serve all rooms and zones assigned to these system types For the compressors and whatever type of heating will be used the user will need to go to Create Plants The AirCooled Unitary equipment category contains all of the rooftop compressor models The specific type of rooftop can be selected using the Equipment Type menu on the Cooling Equipment tab For the heating side a gas fired heat exchanger boiler and or electric resistance equipment category can be used depending on what is appropriate for the model The specific type of heating equipment can be selected using the Equipment Type menu on the Heating Equipment tab If two different heating sources will be used in the same system gas fired heat exchanger and electric resistance reheat two separate heating plants will need to be created The appropriate coils should be assigned to the heating plant s in Assign Systems to Plants Q On the System Zone or Room Checksums reports why are the ventilation airflows for cooling and heating not equal A Three scenarios can typically cause ventilation airflows to differ 1 For a VAV system the minimum stop position for the VAV box has been set too low or has no
490. se The requedbed cold rater fin hee it fred ebke dary that cid ppi ial ae Wiebe AZALIA Col fl Kirai Labid beer Dh rue of poet ra hee old pub God Geeta a ur Geass Geely a iaer pee eae E Coed aa Say SRO ed E Rive Faded bersua The requedhed oud seater fin bene ip i tag LT i fC 7 6 76 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM0O01 EN Selecting a chilled water cooling coil using TRACE 700 output 8 In this case a larger fluid temperature rise 12 F instead of the default 10 F and a lower entering fluid temperature 43 F instead of the default 45 F are one of the input criteria sets that can be changed to get valid cooling coil selections After the change click Run and view the coil selection data and run messages for each of the coils Refer to additional items 1 5 listed below for recommendations on selecting the appropriate coil for the selection Dewy Ophons Fletigecand Options Gerais User Detined An Feta results Additional items 1 General rules of thumb and advice for HVAC cooling coil selections a 500 to 600 ft min for the maximum coil face velocity to avoid moisture carryover Some coils can go as high as 750 ft min Refer to the recommendations from the manufacturer b As the face velocity increases the capacity of the coil and the pressure drop across the coil increase c 3 to 6 ft sec for fluid velocity in tubes Above 8 ft sec can ca
491. sed in heating mode and reheat is used in reheat mode Please refer to the System Type Characteristics section of the Help file for additional information related to coil sizing and location In general schedules should not be entered for the coils The default schedules need to be used for the coils to operate properly The schedules for internal loads ventilation and so on are the appropriate place to adjust the loads seen by the coils Additional items 1 Itis usually easier to make changes to the Create Rooms section of the programs via the Templates For instructions on using templates please refer to Using templates on page 6 125 2 For assistance inputting the plants assigning the coils and creating utility rates please refer to the appropriate sections of this manual for instance Creating utility rates on page 6 150 6 174 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Altering a load design file for energy analysis lla To create an archive file 1 Archiving and un archiving instructions storing library members with project files Verify that the file name of the job to be archived is 15 characters or less If longer than 15 characters choose File and Save As and shorten the file name Close the project file by clicking Close on the File menu if a project is open Click Archive Project on the File menu Select the desired file filename TRC to be arc
492. selected TRACE 700 assumes that if there is no Time of Day schedule then all hours are on peak A Time of Day schedule needs to be added to each of the energy sources that have on and off peak charges To create a Time of Day schedule select Time of Day as the Schedule type in the Schedules library and copy or create a new Time of Day schedule Energy Only m Ihe utility company has been applied to all Utility types and a Time of Day schedule is selected Verify that all utility tyoes have on peak and off peak rates Otherwise not all off peak consumption will be accounted for in the economic calculations The user can also disassociate the Time of Day schedule from individual utilities to correct this problem Energy Only m No demand charge has been input in the utility rate This is often a sign that a blended rate is being used Blended rates combine the charges for electric demand and consumption and give inaccurate estimated energy costs Demand charges can be 50 percent or more of the cost of electricity and need to be modeled separately to give an accurate picture of the cost to 6 18 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Common modeling mistakes operate the building If the utility company charges for demand demand must be modeled separately from consumption Energy Only m The recurring cost Is input with an actual year incurred for example 2015 This means that the cost will neve
493. set his example uses a forward curved fan with a variable frequency drive Then choose an appropriate fan type to represent the secondary fans in the fan powered VAV terminals 3 Enter the static pressure required for each fan type CDS PRMOO0O1 EN TRACE 700 User s Manual Sample scenario Parallel fan powered VAV terminals deliver supply air to the occupied spaces in a building Fan pressure optimization is one of the control strategies implemented by the building automation system The BAS polls the individual VAV terminals to verify that each is receiving the airflow needed to satisfy the space load It then modulates the supply fan which is equipped with a variable frequency drive to satisfy the VAV terminal with the largest load Epnra WAV vah Flic S005 Min Flew Del aul Changeover pre WY Charger Epiri WAY vaih Load Hi Tpit WAV wath Hahaa Didia Dud WO System description izide system Paaie F arrPoweed VAV Fan cycling schedule No lan cycing kw Cinrin wg Avollable 100 kw Citrrin wg Avadabie 100 kwim v okatie 100 kiw Cim Avodsbhe 100 kwi Cim Available 100 kw Cim Avelsble 100 Avaksbie 100 Equi ppo PE VED Crt Zore Riran Piraadid carved eth YFC ard Cita Comments Ex Fikia Ful iiad energy o ot ee Chere w To model the primary fan selected above TRACE 700 uses an unloading curve that Is not pressure dependent enabling optimization based on the critic
494. sly when the building is occupied During unoccupied hours the fan 5 4 System Control Strategies TRACE 700 User s Manual e CDS PRMO01 EN Fan cycling cycles on off when the thermostat set point driftpoint temperature is exceeded Figure 5 2 on page b 4 illustrates this control strategy Create Systems Selection 5 x Altemative 1 or To mMm od el a fa n cycl i n g System description System 001 Single Zone Strategy System category 1 Select the desired type of airside system in this case a single zone constant volume system nn New Constant Volume Non mixing Constant Volume Mixing c Heating Only OpY Underfloor Air Distribution Induction Ce Displacement Ventilation Chilled Beams T H g Advanced l Or 7 ag ts System type 2 Enter the type and static Computer Room Unit Fan Coil pressure of the supply fan Incremental Heat Pump to describe it Packaged Terminal Air Conditioner 3 Choose the appropriate fan cycling schedule For this scenario pick cycle with occupancy Sythem description System 001 Single Zone Fan cytiing schedule Cyce wth ccraguanny 4 For additional information related to how the fan wsoue ehcp Rate Enemy Re Unk cycling schedule and the fan i Aol adele ete eee ek 105 schedule interact refer to nen eben W pwc Abt 05 Frequently asked pee ae Ae CoN questions on page 6 20 Fan cyc
495. sor efficiency For a given load reducing the flow rate through the condenser or evaporator increases the difference between the entering and leaving water temperatures colder water leaves the evaporator and warmer water leaves the condenser Figure 3 8 illustrates how this phenomenon affects power consumption Although the compressor works harder to provide additional lift the cost savings that accrue from smaller pumps and more efficient tower operation more than offset the drop in chiller performance Figure 3 8 Effect of lower flow rates in chilled water plants 900 000 Pee cee tesos eose Pee cee 800 000 700 000 pumps ss pumps ss pump 600 000 500 000 400 000 300 000 annual energy consumption kWh yr chillers chillers chillers 200 000 100 000 12 F AT evap 18 F AT evap 18 F AT evap 10 F AT cond 10 F AT cond 15 F AT cond Application considerations m Evaluate the effect of low flow rates and large temperature differentials on the entire chilled water plant The design that CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 33 Low flow chilled water systems most benefits the chiller may not yield the lowest overall energy consumption for the plant mM Some climates may preclude cooler leaving tower water temperatures In such cases raising the condenser AT to 15 F requires a 5 F increase for the water leaving the condenser Although this will degrad
496. special report Thermal Storage for HVAC designs that include thermal storage The report provides an hourly profile of ambient conditions and plant level cooling loads as well as heat pump loads heat pump energy consumption and condenserloop temperatures for hot and cold storage applications The illustrations on pages 3 70 and 3 71 demonstrate how to model the airdistribution cooling and heating functions of the WSHP system and then assign the coil loads CDS PRMOO01 EN e TRACE 700 User s Manual Cooling and Heating Plants 3 69 VWatersource heat pump system on To model an applied 5 Alomaive 1 WSHP system begin by he aa 1 defining air distribution a La 1 Pick Water Source Heat Cerna Ve Non eana Heating Ordy pu Pump as the system type hisin eain tcc Then click Apply to save Cnued Beant t 5_ Adena your entries Syitem ype q 2 On the Fans tab select PA SSEM Hydronic in heat pump fan and enter 0 5 for the static pressure VAV wF oond Flow Skan Hesling Vientiahon ad Hea 1 bd Sytem depcription fw SHP Wata Sounce Heat Pump Fan cpcing schedule No tan cueing lla Next describe the cooling and heating plants represented by the WSHP ae A system and backup boiler eem A e stern en Aveilsble 100 i Momm ehea Aurel 1 000 3 Drag the appropriate icons ee with Avadable 100 Awali 1005 from the Equipment Category section to de
497. ssure between the condenser and the evaporator by m Modulating the speed of the cooling tower fans or adjusting a tower bypass valve as shown in Inset A of Figure 5 9 to control the entering condenser water temperature m Adjusting the condenserwater flow rate using a pump equipped with an inverter and a variable frequency drive Inset B Figure 5 9 Methods for controlling condenser pressure differential pressure controller butterfly valves actuator to from chiller condenser cooling tower variable speed drive condenser water chiller evaporator refrigerant condenserwater pump gauge line pump differential pressure controller chiller condenser refrigerant gauge line chiller evaporator Inset A Inset B cooling tower bypass variable speed condenser pump System Control Strategies TRACE 700 User s Manual e CDS PRMO01 EN Condenserwater reset Application considerations m Chiller efficiency represents only part of the total operating cost for a chilled water plant Use a building automation system capable of controlling a plant components m Contact the chiller manufacturer to determine the differential refrigerant pressure that will maximize efficiency while ensuring adequate refrigerant flow and lubrication m Although the butterfly valves associated with the cooling tower bypass provide excellent control they also increase the first cost of the system m Be sure to maintain
498. st POTas se ecer lbs co DT ADE TRANE In this case start with maanu Electric consumption E oean vecors U Paa ll Next select the Rate iri a c type On peak Off peak Defend sates endowed Oem df and so on If there is only nsere G ore sf one set of rates in other words no Time of Day In this example the utility charges 0 062 js as a New Osten schedule the utility kWh for the first 2 500 kWh 0 032 kWh Eww No shoud hedaiedas for all remaining kWh a customer charge of 50 00 each month regardless of usage Define th on peak SME and a fuel adjustment charge of 0 0189 remaining parameters as kWh necessary Note Minimum charge is not the same as customer charge Refer to F1 Help T for additional details regarding how these two charges differ Also if on peak and off peak rates are being defined the customer charge should only be included in one of the rates preferably the rate that occurs each month 6 152 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Creating utility rates 7 Click New Definition to define the next utility in the rate structure This time Electric demand will be defined Define required parameters as necessary IMPORTANT NOTE Zero cannot be entered as the rate However 0 00001 can be entered to approximate zero In addition minimum demand and ratchet are synonymous Assuming that 6 000 kWh are consumed during January t
499. stem exhaust airflow is insufficient the rest of the regeneration airflow will be made up of outdoor air Select Outdoor if outdoor air is used exclusively as the regeneration airstream Select System Exhaust if main system exhaust is used exclusively as the regeneration airstream If a liquid desiccant is used and the system exhaust varies in volume due to varying ventilation rates do not use this input for the exhaust side deck use Outdoor amp system exhaust mix to get the required constant regeneration airflow Select Room Exhaust if the room exhaust airflow is used exclusively as the regeneration airstream Room exhaust airflows are input on the Airflows tab of Create Rooms If no room exhaust is input then all exhaust air will be at the system level Also if a liquid desiccant is used and the room exhaust varies in volume due to varying ventilation rates or room exhaust schedules do not use this input for the exhaust side deck use Outdoor amp room exhaust mix to get the required constant regeneration airflow Note If the proper airstreams are not selected for the energy recovery transfer device then the device will not function correctly or may not function at all The Airflows section of the System Checksums report can be used to verify that sufficient airflow is available to be used for energy recovery transfer Room Exhaust Rm Exh on the System Checksums report and System Exhaust Exhaust on the System Checksums
500. sts for a Utility electricity water and so on unless a definition has been created in the selected rate structure sini Wiedow Hep Ph vew Options OVTa lt Pte eerisy ea crernsFf uSe Rate Definition Deveriction Noren Tee ot Day Gs u Ere conen G e Mres chug f Shut pened inawr Endpeiod bemo J Rate ype Pres 6 Mrans demand Fuel adjaitmart foc In this example the utility Charges tutemecnss fir 0 065 kWh for on peak kwnawiteg fio consumption a customer charge of 14 00 each month regardless of usage and a fuel adjustment charge of 0 01 kWh TRACE 700 User s Manual e CDS PRMO01 EN 6 156 Advanced Usage and General Modeling Tips Creating utility rates 7 Click New Definition to define the next utility in the rate structure This time off peak electric consumption will be defined Note Minimum charge is not the same as customer charge Refer to F1 Help for additional details regarding how these two charges differ Also if on peak and off peak rates are being defined the customer charge should only be included in one of the rates preferably the one that occurs each month 8 Click New Definition to define the next utility in the rate structure This time electric demand will be defined Select the rate type on peak off peak and so on In this case start with on peak CDS PRMOO01 EN TRACE 700 User s Manual sini Opia Window hip 3 Ph vw OTE lt t
501. symbols and so forth should not be used In the room names 2 If the dimensions of the room are changed in TRACE 700 the new dimensions will not be reflected in the CAD drawing Note If errors occur during the import or export process please install the latest MSXML from Microsoft from htto support microsoft com detault aspx scid th EN US sp 6 188 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN gobXML import and export Importing a load design Version 3 x or Version 2 x file Old TRACE Load 700 files lds extension can be imported for use in TRACE 700 version 6 x tre extension It is recommended that the import process be done from the TRACE 700 projects directory Typically the projects directory will be CACDS TRACE700 PROJECTS Also the import process should never be attempted from a network drive Note This process is not required for version 4 x files 1 Start by opening TRACE 700 version 6 x me TRACES 700 for exchrsive use by and choose to open an Domn an Erisin Project 1 im existing file Mew Coenin a tow Projet or 2 Select the Files of Type as A Load 700 Files This Te a should cause only lds files to appear in the window 3 Select the file to open and click Open A message should appear that will ask you if you would like to import the old project file into the current version of TRACE 700 ix 4 Click Yes TRACE 700 will create a file with the
502. t members already created for this system Evap N transfer Pamp and ss cu gt Equipment schade vsti 1 000 Cond energy transfer oo 7 Demand intr p pump 16Configure the back up heating water system on the Heating Equipment tab by choosing a boiler type capacity full load energy rate hot water pump type and pump full load consumption rate 3 80 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRM001 EN Central geothermal chillers Variable refrigerant flow system Variable refrigerant flow VRF systems use a combination of indoor and outdoor units to provide cooling and heating to conditioned spaces within a building In a typical VRF system each room Is served by an indoor unit located in or near that room Indoor units may be unducted attached to the ceiling or wall of the room or ducted located in the ceiling plenum or closet Each indoor unit contains a refrigerant to air heat exchanger and a fan typically multi speed All of the indoor units are connected to an aircooled condensing unit located outdoors using a common set of refrigerant pipes Outdoor units contain one or more compressors and an aircooled condenser In some applications the indoor units may be able to handle a portion of the outdoor air load however a dedicated outdoorair system is typically used with a VRF system Multiple configurations are available for the indoor and outdoor units Using a heat pump outdoor unit
503. t been input To remedy this situation look at the Room Checksums reports and find a room with unequal ventilation rates If the reported minimum airflow Refer to the Airflows section of the report is lower than the cooling ventilation airflow the minimum stop for 6 26 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN Frequently asked questions the VAV box will need to be raised to at least the cooling ventilation airflow If the VAV minimum stop input on the Airflows tab of Create Rooms is higher than the cooling ventilation airflow check the VAV minimum airflow schedule If a schedule other than Available 100 is used change back to the default schedule 2 A schedule is being used that causes the ventilation rates to differ between the cooling design and heating design calculations For example if a standard TRACE 700 internal load schedule People Office Lights School and so on is being used for the ventilation zero ventilation will be calculated for the heating design portion of the simulation This is because standard TRACE 700 internal load schedules are O percent for the heating design calculation so that credit will not be taken for the heat generated by the internal loads Selecting a standard TRACE 700 internal load schedule for ventilation tells TRACE 700 to zero the ventilation for the heating design calculation as well To remedy this situation select a ventilation schedule f
504. t is typical for that month A calendar code defines the number of occurrences for each day type Figure 2 15 Choose a simulation method me TRACE 700 C CDS5 TRACE700 Projects TRACEOOO4 tre Use this entry to choose between a reduced year and a full year analysis tanda 1478 E Ape BOG PM ted to Fen ping TH ik serene cd comprises lo This entry defines w Library Template Editors sloj Fle vew Options Window Melb FOTEaMte Ose iE coms 4Meul TRANE Existing calendars can be displayed by clicking Calendars on the Libraries menu J To create a different calendar use i the Library Template Editors 1 Fem Piety m Fi pau faa By contrast a full year analysis uses standardized weather data for all 8 760 hours in a year to calculate the actual coil loads for each hour Sometimes described as an 8760 analysis it can have CDS PRM001 EN TRACE 700 User s Manual Program Overview 2 23 Performing basic tasks alla You can use the following types of weather files in a TRACE 700 analysis typical meteorological year TMY M2 E test reference year TRY E California Energy Commission CEC energy efficiency standard wy2 1992 95 CEC 1988 CTZ 1978 m TRACE 600 weather WIR E Canadian energy codes CWC E ASHRAE weather IWC E 2 24 Program Overview Performing basic tasks separate schedules for nine different day tyoes the seven
505. t it can also cause excessive cycling and discomfort To provide comfort cooling and heating air to air heat pumps rely on two retrigerant to air heat exchangers one located inside the building and the other outside During cooling operation the heat pump operates as a conventional air conditioner reftrigerant passing through the indoor coil picks up heat from the space cooling It and then rejects that heat outdoors when It passes through the outdoor coll The refrigeration cycle operates in reverse during heating operation Ambient heat transfers to the refrigerant passing through the outdoor coil and is then released to the space when the refrigerant passes through the indoor coil Supplementary electric resistance heat typically serves as a backup during defrost cycles and when the heat pump is unable to satisfy the heating load Backup heating is especially important in cold climates because the capacity of the heat pump decreases as the temperature outside falls Figure 3 17 Operating modes of air to air heat pumps cooling mode heating mode compressor compressor r reversing reversing valve valve la indoor coil indoor coil outdoor coil f ra B Tt j filter drier Cn rm filter drier c g Ur outdoor metering device coil metering device check valve check valve Application considerations Most air to air heat pumps can provide cooling at ambient te
506. t mrwrun and al system smdan schockies Note Definitions cannot wrap around a year For example September to May would not be a valid input for the Start and End Months January to May and September to December would have to be input as two separate definitions to complement the definition for Weekday above 2 For people schedules 5 percent or less is considered unoccupied TRACE 700 will use the unoccupied thermostat setpoints at any time the people schedule reads 5 percent or less unless a Thermostat schedule has been Input in which case the Thermostat schedule will determine the setpoint in the space 3 The Reset and lockout table found at the bottom of the Schedules tab in the Schedules library can be used to simulate different control strategies For example if the room exhaust fan were to turn off only when the temperature in the space was less than 50 F the following schedule and reset and lockout information would be input 4 The above Reset and lockout table tells TRACE 700 to reset the room exhaust airflow to 0 percent off when the room dry bulb CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 141 Creating schedules lajxj Fie View Opio Window Help OTa 2S A ZiT EINA oco mamaw E Schedule Library Shedd ype Utin y r Schodde Deiniion Rat End Morth i anusy December Dap type Cooley dengn Surin iv Deteription Room Exhaust Schedule Seredsbon y
507. t side deck Direct cod echado Ean fob om 4 Max outdoor ak J then stage 1 will be upstream of stage 2 air stream will be used to precool and dehumidify the ventilation air As a Schodde S E h Stage Antone Energy Recowerp Transter Stage 2 Aiton Enengy RecowenT tanata resu t ystem X aust Type Totabenesgy wheel IQA precondticr Type Nowe detaan will be selected Svesidedeck Vertioncn women si aaa anne A Extrtide deck Sytem exhaust Schede Avalatie 100 Note If the proper airstreams are not selected for supply side and exhaust side decks of the energy recovery transfer device then the unit will not function correctly or may not function at all The Airflows section of the System Checksums report can be used to verify that a specific airflow is available for energy recovery On the System Checksums reports Room Exhaust Rm Exh System Exhaust Exhaust and Return m Select System Exhaust if main system exhaust is used exclusively as the exhaust side E Select Room Exhaust if the room exhaust airflow is used exclusively as the exhaust side Room exhaust airflows are input on the Airflows tab of Create Rooms If no room exhaust is input then all exhaust air will be at system level z i Ahemaive 1 air Return Air System description Syam 001 Seiat FarrPoweed VAV Evaporative Cooling Economizer _Careet 5 Choose the schedule that 7 yee Type Nore bd pam describes when th
508. t table HOTE T Schedule Library als xi Schedule hype UMration n Schedule Delndion Desception Erangi Buding Occupancy Simulation type Reduced yew Di a eee 1 C Faye Conrerents Sample ol yoa tourd scheckded occupancy for a aking Schedde type Utilization Oesenghon fE aargie Puking Occupancy Simdan ype Reduced year O Filyos Comments Sarel of yeartound scheduled ocoupancy for a bulding s December cone apexes DaDa Sonadeg iran zj p hekk Diin G Slat ioc foci Bl Month Heng dengn Resins Simulation ae e Redad pee i Fulyan Dap tpe cl Comments Sarr A Phair creer ia beat A Lianuary Disnembes Lacing design ka Wooky arena D irii Saidiy be Sure Dil Definition TRACE 700 User s Manual e CDS PRM001 EN alls Standardized 8760 weather data for a full year analysis can be purchased from various U S federal government agencies or downloaded at no charge from various Web sites For example ASHRAE IWEC International weather can be downloaded at no cost from tranecds com Refer to Adding weather locations and activating the 8760 calculation methodology on page 6 167 for additional information regarding simulations and adding weather libraries A reduced year analysis calculates coil loads by month for a design day a typical weekday a typical Saturday a typical Sunday and a typical Monday using 24 hours of weather tha
509. t that cools the outdoor air to 70 F dry bulb during the cooling season or heats the outdoor air to 68 F dry bulb during the heating season before delivering the conditioned outdoor air directly to the Individual spaces Note In non arid climates this approach may not adequately dehumidity the outdoor air m When the outdoor dry bulb temperature is greater than the cooling supply air dry bulb setpoint the dedicated outdoorair unit will cool the entering outdoor air to the cooling supply air dry bulb setpoint System Design Options TRACE 700 User s Manual e CDS PRMO01 EN Dedicated outdoorair systems 1 Start by selecting Fan Coil as the system type On the Dedicated OA tab select the type of dedicated ventilation unit to be modeled In this example the dedicated ventilation unit will supply air to Spaces at a specific dry bulb Therefore Cool Heat will be selected m VVhen the outdoor dry bulb temperature is less than the cooling supply air dry bulb setpoint the dedicated outdoorair unit will heat the entering outdoor air to the heating supply air dry bulb setpoint This example will cover how to model the airdistribution system steps 1 8 model the cooling and heating equipment steps 9 11 and assign the loads from the coils to the equipment step 12 E Create Systems Selection Akaina 1 Syrtem dercnphion Fan Cody ard DOAJ Fan Cod lrir a Haa Pury Prka T aia fur Cor pa Cais Varia
510. tandard 62 1 calculation methods The ASHRAE Standard 62 1 calculations in TRACE assume that each VAV box is at the minimum reheat setting when determining the critical fraction of outside air for the system This can be conservative if all VAV reheat minimums are set to the same value or when utilizing the default reheat minimum that comes with each TRACE system selection In reality the expected minimum airflow at the worst case outside air condition analyzed will likely be greater than the reheat minimum for most VAV boxes when in cooling mode Adjusting the reheat minimums in each VAV box to the expected minimum values can reduce required outside air intake however in most cases this will increase reheat energy when performing an energy simulation m Designers should account for occupant diversity in cases where the design population is significantly larger than what the actual population will be in the building m lo ensure that each space receives Its specified ventilation airflow by automatically increasing VAV reheat minimum settings when they are set lower than the ventilation requirement check the Force VAV minimum always gt nominal ventilation during design check box on the Change Load Parameters screen 4 92 System Design Options TRACE 700 User s Manual e CDS PRMO01 EN ASHRAE Standard 62 1 1 In the Apply ASHRAE Std 62 1 2004 2007 field select Yes to set the zone level outside air requirement per the standard
511. tant condenser temperature unloading curve and the corresponding condenser relief curve refer to the points in Additional items on page 6 149 for instructions on creating a custom ambient relief curve Pimli RTWAIL25 3 Tag RTWA 1 Part Load Performance Note This unloading curve reflects constant condenser water temperatures Refer to Additional item 3 on NPL page 6 149 for additional Constant Conderber information 1 Deg F 0E C riy IRANE Senes RUT MM Chiller Note IPLV SEER NPLV and so forth are not valid inputs for TRACE 700 They combine unloading curves and full load energy rates and are not specific enough for detailed energy analysis In the following example a custom watercooled rotary liquid chiller will be created from data provided by an equipment selection program CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 143 Creating equipment and unloading curves 1 Click Equipment on the Libraries menu and then click Cooling on the Equipment menu The Library Template Editors program will display the Cooling Equipment window To create a custom piece of equipment click New To copy an existing piece of equipment select the desired piece of equipment and click Copy In this case click New to create a completely new water cooled helical rotary chiller 6 144 Advanced Usage and General Modeling Tips Shida The Cooling category is the
512. tat set points 1 cy Open the Schedule library and pick Thermostat as the schedule type 2 Create a new schedule and name it Morning Warmup Add comments if desired to further describe the schedule 3 Define a Weekday schedule with an after hours set point of 55 F and an occupied set point of 68 F that is also in effect during the morning warm up period from 5 a m to 7 a m To maintain the 55 F set point throughout the weekend define a separate schedule for Saturday and Sunday CDS PRMOO1 EN TRACE 700 User s Manual Sample scenario A gas fired rooftop air conditioner and VAV terminals with electric heating coils serve a small building Either heat source can handle the design heating load of 200 MBh However the electric heating coils only operate during scheduled occupancy that is from 7 a m until 8 p m on weekdays The gas fired furnace in the rooftop air conditioner provides heating at night during morning warm up which begins at 5 a m on weekdays and on weekends The illustrations that follow demonstrate how to create schedules that simulate morning warm up Steps 1 3 determine equipment availability Steps 4 5 and assign the schedules to the appropriate rooms and equipment Steps 6 9 Click New Definition to define a new timetable for a different day type or month within the current schedule fi scheen Libary cha Scheck e lype Theemoceat 1 Schedule Defirtion E
513. tching from the reduced year to 8760 methodology steps 10 12 Advanced Usage and General Modeling Tips 6 167 Adding weather locations and activating the 8760 calculation methodology 4 Click Import 5 On the Files of Type menu select the type of weather that you would like to import TMY TM2 TRY WYEC WYEC2 IWC and so on Select the weather file that you have downloaded and renamed and click Open 6 Select the Region and Subregion and then input the name of the Location Avoid using special characters like percent signs apostrophes quotation marks and so on Note You CANNOT use the same names that are currently being used by existing weather locations 7 Change the design conditions that appear on the left hand side of the Weather Import screen to the desired design conditions Then click Import 8 Save and then close the Library Template Editors program and return to your project 9 Click Select Weather Information choose the appropriate subregion and the weather location and click OK d Fh Vew Opens Widow hb POVYE Bte Ber ivy St conts 4g Ff TRANE i Weather Library General Information Rogon Subregion Location Urzad States Noth Corrs Prono OO e uaa m a LT tis gan Lock in 3 Preet aE Longtude 03 amp aj LACROSSE THY Altude 1210 R je 4T ours me i w psa _ A mea OADB F Summer BE m 5 Fiet of Ippe Typed Metercrologea
514. te TRACE 700 defaults Pte Goethe m to 65 F supply air for all eon displacement ventilation systems It is not recommended to set the supply temperature below 65 F 4 90 System Design Options TRACE 700 User s Manual e CDS PRM0O01 EN Displacement ventilation ASHRAE Standard 62 1 ASHRAE Standard 62 1 prescribes minimum breathing zone ventilation rates and a calculation procedure to find the minimum intake airflow needed for different ventilation systems These rates and procedures must be used to find the design outdoor air intake flow which establishes the required capacity of the mechanical system equipment The first step is to determine the minimum ventilation that is required for each different space type This is also known as the zone level procedure The ventilation requirements for individual Space types can be found in Table 6 1 of Standard 62 1 Once the minimum ventilation requirement for each space type has been determined equation 6 1 of the standard is used to calculate the required amount of airflow for the breathing zone The effectiveness of the air mixture within the space called the Zone Effectiveness is determined based on the position of the supply diffusers and return air grilles in each zone This factor also accounts for any ventilation that would not be used within the breathing zone that could be recirculated into the space The zone level procedure concludes with the solving of equation 6 2 to d
515. te condenser ai or water cooled pick a different piece of equipment in Create Plants The piece of equipment depends on the type of compressor being modeled and whether it is air or water cooled There are several types of compressors with both air and water cooled options including scroll reciprocating centrifugal and helical rotary The added inefficiency of the split system over a non split system would be included via a decrease in the efficiency of the compressor in the selection Q What is exhaust heat and why is it negative A Exhaust heat is heat that is picked up by the return air in the plenum but is exhausted out of the building before it can return to the cooling coil As the return air travels through the return air plenum it absorbs some of the load that is in the plenum e lights roof load and so forth As a result the return air temperature rises However some of this air is exhausted before it returns to the cooling coil Because the coil never sees the load the program removes the portion of the return air load that is exhausted from the coil totals to balance the load Exhaust heat is not a credit It is an energy balance Note Exhaust heat will be zero if the system exhaust Is zero 6 22 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Frequently asked questions Q The Checksums report shows that the heating coil peaks during Heating Design What is Heating Design
516. te for the secondary fans on the Fans tab in your TRACE 700 project or use the Library Template Editors program to customize an existing fan type The new full load energy rate can be determined from the ratio of airflows System Design Options Cold air distribution 4 78 TRACE 700 User s Manual e CDS PRMOO1 EN Chilled beams TRACE 700 incorporates two chilled beam strategies passive and active Passive chilled beams consist of a fin and tube cooling coil contained in a housing or casing suspended from the ceiling Chilled water passes through the tubes Warm air from the space rises toward the ceiling and the air around the chilled beam is cooled causing it to descend back toward the floor It essentially cools the space through convection Passive chilled beams are used for sensible cooling only no latent cooling no dehumiditication A building with passive chilled beams requires a separate mechanical ventilation system to deliver the required amount of ventilation air to each space and deliver that air dry enough at a low dew point to offset the space latent loads and maintain the indoor dew point low enough to avoid condensation on the chilled beams Figure 4 18 Passive chilled beam ceiling mom HHH Y y y y y perforated metal casing coil Active chilled beams also consist of a fin and tube cooling coil contained in a housing suspended from or recessed into the ceiling Active chilled bea
517. te the other chiller Caupmert Category i amp Ar cooled Ar cooled che ur ay 6 wo m Water pounce Doder Electi Gertred heat hes puno lesntance exchanger a poi act z F SG As lt ooked Cooling tower Pures Theme conderaet AO Alcinae 1 a A irany 1 Configuration Cooking plants as Cooling part 007 JE SEL Wotercocted chs 002 Part Wirard Heating plants Ik Heating plore 002 How Cig Para New Hig Ed ome Energy Mgmt Coding plant Cocirgpise 001 Hestrejecson E ns tee OEC eS o AU Hosh mieri wt bubait F Equipment type cothinemad Chiles Hewtes Thermal storage New Equip TRACE will automatically add heat of compression to the entered value to account for compressor heat If this entry is left blank TRACE calculates this value and sizes the first chiller for the entire cooling capacity Cooling and Heating Plants Central geothermal chillers S RER one r Bape Utility Misc Accesso a as These energy consumption rates are at design chiller conditions for the cooling and heating mode TRACE 700 User s Manual e CDS PRMOO01 EN 9 Select the back up heating plant for Reject heat to plant 10Select Ground loop for Reject condenser heat 11Click Cooling Plant and Geothermal Controls to open the Plant Controls dialog box 12Choose the geothermal loop type by specifying the temperature of the loop entering the building in
518. ted the Doo ie Coding neob et dybub 170 f Dedicated Ventilation Heating Coil schedule Heating sgy ar dy bub 68 F Cong nee atdeweont f defines the hours of available operation of the ventilation heating coil The optional Sa ee ventilation heating coil is available for any hour that this schedule reads 1 percent or greater Cooling cod Avetable 100 Heatry col avveskatle 100 a 5 Operis avantatie 100 The Optional ventilation fan schedule defines the hours that the ventilation unit can iln OO e Dedeatedoa I Operate If the Optional ventilation fan schedule reads 1 percent or greater the fan is available that hour CDS PRM001 EN TRACE 700 User s Manual System Design Options 4 53 Dedicated outdoorair systems 6 Select the dedicated ventilation deck location This tells TRACE 700 where to supply the preconditioned outdoor air For this scenario the outdoor air will be delivered to the heat pumps As a result Return Outdoor Deck will be selected 7 Select the level of the ventilation deck location For this scenario one large dedicated ventilation unit will condition the outdoor air for all of the rooms assigned to the WSHP airside system so the coils should be set at the System level Note For additional details on Systems refer to the System Type Characteristics in online Help 4 54 System Design Options Selection im Cirdscabed 1A Retur
519. ted Reheat Underfloor Air Distribution CY Fan mire feed Tuppi amr path duci location Tostu ver pathi i F feos ia i cii Disc Peivi Deck Note The ventilation reset option allows system outdoor intake dampers to dynamically reset ventilation airflow for hourly changing system loads and airflows TRACE 700 User s Manual e CDS PRMO01 EN Additional items x System description VAM Reheat Classrooms System type Variable Volume Reheat 30 Min Flow Default Cancel Supply fan motor location Sum o Return fan motor location Reun Fan configuration Draw Thru Fan sizing method Block x Supply air path duct location Return Air gt Return air path Plenum h Block cooling airflow oOo o m o Cooling coil sizing method Bok y Cooling coil location System o y Ventilation deck location Retum OutdoorDeck gt System ventilation flag 2 ASHRAE Std 62 1 2004 2007 w Vent Reset Apply ASHRAE Std 62 1 2004 2007 People Averaging C Yes No Warning The fields marked in red are core ASHRAE Std62 Max Vent 2 Ratio Allowed I 1 components of this system Changing these values can drastically affect how Population Diversity non DCY Rooms only 100 the system operates Please make sure you are aware of the total ramifications CO2 based DCY None Proportional Control Single Setpoint before you make such a change 1 The ASHRAE Std62 Max Vent Z Ratio Allowed field
520. temperature from 55 F to 45 F reduces the supply air volume by 30 to 40 percent Reducing the amount of supply air needed in an application lowers the first cost of the HVAC system smaller fans and ductwork smaller overall ampacity Cold supply air also lowers the relative humidity in the occupied space Improving indoorair quality Figure 4 17 Effect of cold air distribution 100 9 55 F supply air E 34 485 cfm 80 E 4 0 In wg total 2 We static pressure 2 60 e m fan 379 bhp a 45 F supply air 40 hp motor m 20 900 cfm T a E 4 0 in wg total 2 static pressure P a m fan 23 0 bhp 25 hp motor y 36 40 44 48 52 56 60 supply air temperature F Application considerations Use a vapor retarder on the warm side of perimeter walls to minimize vapor pressure diffusion TRACE 700 User s Manual e CDS PRM001 EN on Begin by defining the air distribution system 1 From the variable volume category choose series fan powered VAV as the system type 2 Lock in the design supply air temperature for cooling by entering the same value for minimum and maximum in this case 45 F Maintain a slightly positive pressure inside the building to pre infiltration Ideally use linear slot diffusers with a high aspiration ratio to provide proper air movement Implement a control strategy that resets the supply air temperature set point to minimize reheat Related reading vent Cold Air Makes Good ense
521. ter Depth is used to calculate the distance of the Daylighting Reference Point from the perimeter wall In addition if the glass dimension method is used Perimeter Depth is used to estimate the field of view seen by the daylighting sensor Perimeter Depth can be selected as the room length or width or manually input for each space soo Carvlighting Paranse ters _ x 8 For Daylighting Reference General Davighting Contos Poon Fisiere Glatt Parsrretert intemal Shade Parameters Point 1 choose Std fatter E EEES Stepped Controller and o S ating Sctade Digighing Retenca i1 Daging Reterenca a2 C a EEEa Om mi Cust click Yes to apply this to all Conteranee ioe fae No Daykghting Conte m Cuig E aaria T h Diyar Contios Ff Contam l rooms Note If daylighting is added to E a space that has no Mochy sesion fenestration then the a eae dayligh ting controls will be en ignored for that space By CDS PRMOO01 EN TRACE 700 User s Manual System Control Strategies 5 39 Daylighting x 10The Glass Parameters tab Denera Qagighting Conis Foon Paver Glos Persmeters intema Shade Pansier allows the user to input the Visible Transmissivity and the Inside Visible Reflectivity No inputs are required on this tab for the example scenario Only glass types used in the file will appear under the Glass Library Member menu Refer to online Help for a table with typical Inside Visible Reflectivity val
522. the TLoop Ent Bldg field Note IGSHPA should only be used for horizontal borefields Vertical bore requires a separate IDF file to be used in conjunction with the project The Custom selection in this field requires a separate Geothermal schedule defined in the Schedules Library When using either IGSHPA or Custom geothermal loop types plant or equipment level thermal storage should be defined to reflect the capacity of the borefield loop 13Enter the geothermal loop flow rate geothermal loop pump type and associated full load energy rate Enter Bidirectional cascade as the flow scheme 14lf a primary secondary distribution system will be used enter the secondary distribution pump type and full load consumption rate xj Pisni derenplion Cooling plant 001 Equant lag Wiaterssooiesd chiles 001 E Fins Grol Type Cs oh Fad cocira Byer tae 44 Pump hull load energ Evapa ane Condenser Water Leaving Aiens Optra Ma Reset Based On Ferat Curve Reset TO Bss Here Here JF F Diir ehled water dta T io F N Dan cond wam deka T 10 F R Ground loop 10 Esku heating war Q avse o Load theddng economizer No Evnpe ates parecian Energy bout Foret heat be plant Equipment schedule rer kreata pareeilye Het gos sahasa kce Plant Controls xj Description Cooling plant 001 Sizing method Peak based on design simulation Heat rejection Type Non
523. the template Finally select the Room template so that the individual templates can be grouped together Click New and enter Office Areas in the description field Next select the appropriate Internal Load Airflow Thermostat and Construction templates for the room type Using templates Advanced Usage and General Modeling Tips Fhar 4 Uw irida EEN Rea E He Con ine sss pes Wal 4 Lw Bock Tine pos Partition 0 75 Gyo Fane ps Gloss bape aie Geert Window Tapis Canned 1 4 b fo Hrighi wa fiz R From iz ft Perum DO ft fetemal Load Airflow Albenatieg hepenption ime Ainii Akamara hall Templates Themett fluro i Canitrschen itvabiray i i i intemal Load dition J Demot J_at 7 loom PELE kef Note Typically the wall height and floor to floor height will be the same value Refer to online Help for additional details Themostt Constuction Boom _ TRACE 700 User s Manual e CDS PRMOO01 EN 8 Click Close Templates and click Create Rooms To start inputting the room data give the room a name Office 101 in this case For the Room template select Office Areas 9 The user now needs to input the appropriate room specitic data size of the space walls windows roots partitions and floors and override any data from the templates that is not appropriate for the space In this scenario the roof wall glass and floor area ne
524. the entire Heoing schede None S calculations Also the building Click New and oo ES a thermostat driftpoints activate enter Building in the iE mamn eee whenever there are 5 percent or undid eon z less of the people in the space Description field Input the Cooling dry bulb setpoint Heating dry bulb setpoint and Relative humidity f the file will be used for energy analysis then the Cooling driftpoint and Heating driftpoint or the Cooling thermostat schedule and Heating thermostat schedule should be input as well CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips determined from the people schedule on a room by room basis 6 127 Using templates 6 128 6 With the general characteristics for the building thermostat setpoints defined click the Construction tab In this scenario the envelope components of the building will be constant throughout the building Therefore a single Construction template can be used for the entire building Click New and enter Building into the Description field Next select the appropriate Construction types for the building override U factors and Shading coefficients if necessary and input the Wall floorto floor and Plenum heights If the building does not contain a certain construction type use the default value In this scenario the building has no skylights therefore the default construction value will be used in
525. the unit 4 Click Controls 5 Choose Yes in the Evaporative precooling box and click OK To save your entries click Apply on the Cooling Equipment tab Heat racion Thamal storage Houry ambient wet bub ott SS Type Corsderwer tari fox Heat Pump em Twe ue S mra Schedule Seorage 7 To create a piece of custom cooling equipment open the Cooling Equipment library 1 On the Main tab choose Demand kming pisiy O Air cooled unitary as the cooling category Equipment schedule valisti poah Hoot gar reheat tor Me dehur diicstion Conling category Ar cooied utay 1 Commerts gt 22 Tore Sme Zore Rooltop CY 2 Choose an equipment type a _ that is similar to the one Cooingype Dra nonmen SCY you want to create 3 Click Copy P Cooling Equipment Main Cooling category r cooied utary Comeert gt 22 Tons Singe Zone fiochiop 4 Rename the equipment nasienie D4 hii type with a meaningful Cosingypa Dra sonn a identifier and add comments if desired 5 On the Options tab choose Yes for the entry in evaporative precooling Evan peecodetincivenns E2 Gy 6 Use evap precool effectiveness to specify Themae foe the efficiency value of the ocne lt SoN evaporative precooling function Be sure to save your new custom cooling equipment when finished 3 56 Cooling and Heating Plants Evaporative precooling of condenser air Dieren pm F
526. them If you choose to do so you can refine the system description by adding information about options ventilation economizing evaporative cooling exhaust air heat recovery Note Block sizing is commonly applied to variable ai volume VAV systems This method considers the schedules for individual spaces and finds the collective maximum load that will occur at any time The program then determines fan and coil sizes based on that maximum load Peak sizing determines fan and coil sizes based on the sum of the maximum load requirements for individual sopaces it is typically used for constant volume CV systems Plant refers to the mechanical equipment that conditions the air heats cools humidities dehumidifies Examples include packaged air conditioners chillers boilers and auxiliary equipment such as pumps and cooling towers Templates and libraries Often several rooms in a building share similar thermostat set points construction internal loads and other design criteria Templates let you enter this information once and then apply it to an unlimited number of rooms If a design criterion changes you TRACE 700 User s Manual e CDS PRMOO1 EN Note The TRACE 700 program includes a separate Library Template Editors program that lets you view the detailed information found in the standard templates and libraries You can also use this program to create new global templates and library members can either ed
527. them from operating in a series coupled pumping arrangement In effect it creates a supply demand relationship at the tee that connects the production supply and distribution demand sides of the system The direction and amount of flow through the bypass line determines the number of chillers operating at any one time This arrangement provides constant water flow through the chillers while they operate It also permits two way valves at the coils with the valves varying the flow based on the cooling CDS PRMOO1 EN TRACE 700 User s Manual Cooling and Heating Plants 3 3 Decoupled chiller arrangement demand Equipping the distribution pump for variable flow by adding a variable frequency drive for example can limit the dynamic pumping head which reduces energy consumption significantly Application considerations E Not all chilled water loads peak simultaneously resulting in the quantity of water flowing at any one time being less than the sum of the peaks load Varying the flow through the distribution loop may permit you to select smaller chillers pumps and piping m Only the water that the loads actually use is pumped This usually results in a significantly reduced flow rate accompanied by an even more significant reduction in pumping energy E None of the unused chilled water bypasses the cooling coils the return water is therefore always at least as warm as It is at full load Warm return water permits preferen
528. tial loading of chillers and accommodates energy saving options such as free cooling and heat recovery Related reading E Chilled Water Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRCO16 EN E Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN Sample scenario Three 500 ton three stage centrifugal chillers are piped in parallel with each other and with a bypass line Each chiller has a pair of constant volume pumps one for chilled water and one for condenser water An 85 kVWV variable volume pump circulates the chilled water through the coils to satisfy the building load The illustrations that follow demonstrate how to define the cooling plant Steps 1 5 and add a secondary distribution pump Steps 6 9 3 4 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Decoupled chiller arrangement llay Define the cooling plant by selecting Create Plants in the Project Navigator window 1 Drag three watercooled chillers to the cooling plant and click the Cooling Equipment tab For each chiller 2 Select the appropriate CDS PRM001 EN TRACE 700 User s Manual equipment type Pick parallel decoupled as the sequencing type Enter the cooling capacity 500 tons If left blank the program calculates this value and assigns the entire capacity to the first chiller Specify the full load ener
529. tion choose whether a chart or a table should be created e From the Component Selection section use the tabs and check boxes to select the variables to be ee Dro FOO Visualiser CADIS TRE TOO Projects Eee TEC MEE imiti Cg amp Hig Cuil Prilike ldonthhy Cig A Hig Col Previies Ez E by Be eer lg Hig Cod Profies iat Foie Satiraj az Data Type oT ime of Year First OSstlo Jany T ae and Boiler Alt a WSHP with DUAS First Last Day First Last Hr 1 24 All Design Weekday Display Options Saturday W Table Stacked C 3D aie Chat F vea Total f 2D Wondsy omponent S lection Airside Clg Plants Htg Plants Miscellaneous Weather viewed Reduced year weather detected O4 Dry Bulb St Louis Missouri OA wet Bulb ia Latitude 38 0 deg O14 Humidity Ratio Longitude 90 0 deg E COBB 940F Cloud Cover E SOWE 7r 0F WODB 60F CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 123 Creating spreadsheets and tables from calculation results TRACE 700 Visualizer f Click OK to accept changes that were made and view the custom graph or chart Note In this example the hourly outdoorair dry bulb cooling loads and heating loads for January for Alternative 1 and Alternative 2 were displayed in a table format 5 To save the custom table or chart input a custom name in the lo
530. tion for each pump 4 Click Controls on the Cooling Equipment tab On the Cooling Equipment Controls screen enter the maximum amount of reset that can be applied to the chilled water set point in this case 5 F CDS PRMOO0O1 EN TRACE 700 User s Manual Application considerations Raising the chilled water temperature In variable volume systems increases the energy consumption of pumps and may more than offset the savings in chiller efficiency If humidity control is critical take particular care to ensure that the warmer chilled water does not cause the loss of space temperature or humidity control To ensure adequate refrigerant flow and maintain proper oil movement within the chiller maintain the minimum pressure differential specified by the manufacturer between the condenser and evaporator Related reading Multiple Chille System Design and Control Applications Engineering Manual Trane literature number SYS APMOO01 EN Sample scenario The chilled water plant for a building consists of a water cooled chiller a cooling tower and related pumps At part load conditions the chilled water set point is reset upward The maximum amount of reset is 5 F Abemstive 1 Cooling plant Coolers piane 001 Heat reyecton type E4510 Conira tower tor Fait Weercodedcher On SY ae Equawmert category W ater cooked cher hd Thamal storage x Type None hd EEA Sequencing ype Suge bd capy p flute y Santas Sc
531. tion of selecting what data to import from the CAD model into TRACE 700 The user will then need to define the template information for the file internal load information construction types and ventilation airflows to refine the room inputs After running the simulation output information from the TRACE 700 program can be exported back to the CAD model Space airflows heat cooling loads and so forth The gobXML standard is in the process of being accepted by most CAD vendors Autodesk and Bentley will likely be the first two vendors to use this feature The import has been implemented in TRACE 700 for a few years now leading the industry and the export functionality is available in version 4 1 5 or greater C D S has completed similar development with Vari Trane Duct Designer VDD can now import files using ddXML Analysis can then be performed on the duct design and sizing pressure detail information can be returned directly to the CAD model through an export feature in the program For additional information specific to goXML go to http www gbxml org CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 181 goXML import and export Exporting gbXML data from Autodesk Building Systems 2005 PU Autodesk Building Systems 7005 NOT FOR RESALE gbML Example dwg EP Fie Edt View Insert Format MEP Common Window Help lO A sAO e eaQ O6 s f i me rik nGRRGS Sear p JO DN 0 gt SHA
532. tiv cooling coil cooling coil e vaii s 100 ot supply air 100 ot supply air 100 A supply air outdoor air r l outdoor air i l outdoor air i oi 1 ot root a I I a n I I direct o indirect oo indirect I evaporative Lann evaporative Lane evaporative F conventional coil coil coil cooling coil i j cooling tower auxiliary chilled water 7 loop chilled water cooling tower aus chilled water water source loop optional loop optional loop water loop optional stage 1 Source g stage 2 Inset A Inset B Inset C direct evaporative cooling indirect evaporative cooling staged evaporative cooling Direct evaporative cooling Figure 4 14 Inset A introduces water directly into the supply air stream usually with a spray or wetted media The water evaporates as it absorbs heat from the passing air which lowers the dry bulb temperature of the air However it also increases the moisture content of the air which raises the dew point By contrast indirect evaporative cooling Inset B uses an additional waterside coil to cool the supply air Positioned upstream of the conventional cooling coil the indirect coil is piped to a cooling tower where the evaporative process occurs This method of precooling does not increase the moisture content dew point of the supply air because evaporation occurs at the tower It is however not as effective as the direct evaporative cooling process 4 40 System Design Options TRACE 700 User s Manual
533. to Air Energy Recovery Engineers Newsletter volume 29 number 5 Airto Air Energy Recovery in HVAC Systems Applications Engineering Manual Trane literature number SYS APMO003 EN Sample scenario To input the type of heat recovery in Figure 4 4 Inset C we will model an office building with a dedicated ventilation unit mMakeup air unit that dehumidifies the outdoor air and then reheats the air to a room neutral dry bulb temperature before the air is delivered directly to the space Watersource heat pump VVSHP units are installed in the ceiling plenum above each room and handle the cooling and heating needs for the rooms To reduce the amount of reheat energy needed and to increase the dehumidification capacity of the cooling coil in the dedicated ventilation unit a coil loop is used to precool the outdoor air stream before it enters the optional ventilation unit cooling coil and then reheat the dehumidified outdoor air after it leaves the optional ventilation unit cooling coil Note For details on modeling the WSHP portion of the system refer to Watersource heat pump system on page 3 68 For details on modeling the Dedicated Ventilation Unit portion of the system refer to Dedicated outdoor air systems on page 4 45 Change Load Parameters cone te Frttmoth Wiewey Ertered actu Cancel Last month Decnmeste Repoted ache Pakha 0 Methodology pa Cooking Buking oemntahon fo dag irom Nath Healing UATO
534. towers Drag the desired equipment category to the cooling or heating plant on the right hand side of the Configuration tab TRACE 700 User s Manual e CDS PRMOO01 EN If you wish you can add options such as chilled water reset demand limiting free cooling evaporative precooling load shedding economizing and chiller sequencing You can also model the energy consumption of miscellaneous accessories attached to the primary HVAC equipment crankcase heaters defrost heaters pilot lights bumps parasitic heat losses and base utilities Like the HVAC system and indoor lights base utilities process loads and parking lot lights for example can represent a significant percentage of the energy consumption for the building Review the equipment defaults to make sure that the completed entries sufficiently represent equipment and system performance To account for the energy consumption of a pump for example be sure to enter a value for full load consumption Note Many of the entries in the Create Plants window are blank by default because they only pertain to certain systems Unless you override the default by entering a value entries such as capacity will be determined by the results of the load calculations alls Assign systems to plants For the program to translate the coil loads by system and by hour into energy consumption by source It must know what systems each cooling plant and heating plant serves To assign each syst
535. ts Planty Dafina Donrecrnic Purarmadert Emeed hk w amp Do the following to activate the 8760 Full Year simulation only required to run an 8760 full year analysis not needed if only adding a new weather location 100n the Actions menu xj click Change Energy es 12 coe Ekes 33 Conca Parameters a pm Decemeer ol E 11 n the Change Energy sem f Parameters move Bassler aerated aed wae 15 change the Simulation equipment capaciiet Ce fe hours to Full year and the AE Note When an 8760 weather file is imported the actual tmy try and Standard so on file is used during a full year 8760 simulation The original file 12Click OK and run all the must be kept in the location in which it resided during the import During the import process the associated reduced year energy analysis weather and design weather are created The reduced year energy sections of the simulation i analysis weather is only used if the user selects a reduced year simulation whereas the design year weather is used by the design simulation to calculate the design airflows and capacities of all coils CDS PRM001 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 169 Adding weather locations and activating the 8760 calculation methodology Altering a load design file for energy analysis The purpose of this section is to show what steps need to be taken to convert a typical file from a load
536. ts of the spaces they occupy Figure 3 18 Applied water source heat pump system cooling tower plus waterto water heat exchanger heat pumps in heating mode heat pumps in cooling mode TRACE 700 User s Manual e CDS PRMOO01 EN VWatersource heat pump system Application considerations m Design the airdistribution system to provide proper ventilation either locally at each heat pump or centrally using a dedicated ventilation system E Heat pumps are situated in or near occupied spaces Provide appropriate acoustical treatments to ensure that the noise from the compressors and fans is unobtrusive E For proper maintenance heat pumps must be located In accessible areas In new buildings this requires coordination with the architect Related reading E VWaterSource Heat Pump Systems Air Conditioning Clinic one of the systems series Trane literature number TRG TRCO15 EN m Water Source Heat Pump System Design Applications Engineering Manual Trane literature number SYS AM 7 Sample scenario An applied watersource heat pump system one heat pump per room provides comfort cooling and heating for a multistory commercial building The pump that circulates water through the common condenser loop is rated for 50 feet of static head A gas fired boiler and an auxiliary pump rated for 20 feet of static head serve as a backup if the condenser loop is unable to satisfy the entire heating load Note TRACE 700 generates a
537. two pumping arrangements is used when the chillers are piped in parallel One arrangement uses a single pump to circulate chilled water through the system The other shown in Figure 3 2 dedicates a separate chilled water pump to each chiller The parallel arrangement in Figure 3 2 represents a swing chiller control strategy that unequally divides the total cooling capacity between the chillers one third and two thirds for example When a cooling load exists the smaller chiller starts first When the load exceeds the capacity of the smaller chiller it stops and the larger chiller starts If the cooling load exceeds the capacity of the larger chiller both chillers operate and share the load proportionally according to their capacity Note To operate as described for the unequal division chiller sequencing with a switchover point must be defined Refer to Switchover control for chiller plants on page 3 17 Figure 3 2 Parallel chillers with separate dedicated pumps chiller 2 chiller 1 chilled water loop partial flow starved coils CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 7 Parallel chiller arrangement Application considerations m Using a single pump to circulate water through the chilled water loop does not provide standby capability m Providing a separate dedicated chilled water pump for each chiller helps maintain the proper mixed chilled water temperatu
538. two types of methods Simply adjust the baseline CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 87 Modeling for LEED alternative s lighting power densities per those found in ASHRAE 90 1 2007 Adjusting these values through Create Templates is the preferred method Note Exterior lighting is modeled through Create Plants on the Base Utilities Misc Accessories tab Refer to ASHRAE 90 1 2007 section 9 for allowable exterior lighting power densities and the ASHRAE 90 1 2007 User s Manual for information on how to apply these values Adjust airflow requirements EAc1 requires the baseline building s performance to be calculated according to Appendix G 3 1 2 5 of ASHRAE Standard 90 1 2007 which reads Ventilation Minimum outdoor air ventilation rates shall be the same for the proposed and baseline building designs An interpretation of this statement was issued in June 2008 to alleviate some industry confusion In short the interpretation states As currently written Appendix G is neutral with regard to ventilation energy so no credit is allowed for improved ventilation system design that would be allowed under ASHRAE 62 1 Therefore the TRACE user must ensure the design system ventilation matches between the proposed and baseline buildings Note The following procedure applies to projects that are following ASHRAE Standard 90 1 2007 without addenda and have defined the ventilation in
539. ty rates installed costs maintenance costs and replacement costs additional depreciable costs can be edited from here Calrudate ane view Reaults j Avoenatnve 1 11 ete Created by wizard Soloct Aa Created by wizard eat Ready Kec Ereg Param i Var Hilts Abana l Epirit Caila D Peia ieia baaki bike cakar dhara Dragn in tens yall ra Haeg Chose Baer Mirinda hore porn ergata F i Hele pies FI Additional items Additional alternatives can be created in a similar manner to Alternative 1 from the Alternative Setup menu If the user would like to input a custom load profile instead of using the default profile then please start on step 8 of Inputting an existing load profile on page 6 118 The accuracy of Chiller Plant Analyzer directly relates to the accuracy of the load profile the inputs for the chiller plants and the utility rate It is up to the user to model reality To transfer files to another PC the Tiles must first be archived Refer to Archiving and un archiving instructions storing library members with project files on page 6 175 for instructions on archiving and unarchiving files CDS PRMO01 EN e TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 117 Using TRACE 700 Chiller Plant Analyzer Inputting an existing load profile If the user has a known load profile and wants to directly input that profile into TRACE 700 TRACE 700 Chiller Plant Analyzer can be use
540. ty rates will be used to help illustrate each of the rates In the example rates the rate structure charged by the utility company will be given the individual portions of the structure will be entered into TRACE 700 and a sample calculation will be provided to help explain the charges Stepped rate In this type of rate the utilities are billed at one rate until the next cut off is reached The rate structure is shown below Electricity consumption m Customer Charge 50 00 charged each month regardless of usage m Rate 0 062 kWh for the first 2 500 kWh and 0 032 kWh for all remaining kWh m Fuel Cost Adj 0 0189 kW Electricity demand E Rate 8 45 kW for all kW over 10 kW E Aratchet rate of 75 percent of the highest kW demand at this location as determined during the preceding 11 billing months is charged by this utility Gas m Customer Charge 10 00 charged each month regardless of usage m Rate 0 530 therm for the first 200 therms 0 499 therm for the next 300 therms and 0 485 therm for all remaining therms TRACE 700 User s Manual e CDS PRMOO1 EN 1 Click Rate structures on the Libraries menu The Library Template Editors program should open to the Rate Structure library Rate structures are used to tell the program what the utility company s charge for electricity water gas and so on alaiz Fie Vew Options Window Help 2 Selectthe rate structure OTAS ezel to be view
541. ual Program Overview 2 21 Performing basic tasks 1 Click in the toolbar to open the Schedule library Then click New Sched to add a new member in that library Pick Utilization as the schedule type Then give the new schedule a name in the Description box Use the Comments box to add a brief explanation optional Click New Definition to begin entering the cooling design and weekday definition for the year Complete the Schedule Definition entries using the information in Table 2 1 on page 2 20 Repeat Step 3 and Step 4 to enter the Saturday and Sunday definition Similarly enter the heating design definition as shown These entries exclude the effect of occupancy from the calculation of the design heating load Click Save to record your entries and make the new Utilization schedule available for any TRACE 700 entry that lists Utilization schedules For additional details refer to Creating schedules on page 6 137 2 22 Program Overview Performing basic tasks w Library Template Editors alajxj Fie Vew Opiom Windew Help POTALARI T IIA Ce mSTARSE TRANE E Schechile Library alz x Descaphen E angir Bulding Occupancy 2 End Morth erway Decemeer Cancel Simulation ype Reduced year C Fulyou Dapp Cocing denon fweekcay x Nosed 1 Correnaorts Sangle of yeartournd schedded occupancy fer a P a bad a eae AAE Osi Defratin Copy Detewtion Prevet and lockou
542. ual value In this case the second Cutoff is at 500 therms not 300 therms 9 Click Save close the Rate Structure library select the Define Economics section of TRACE 700 click Add Rate and click the newly created custom utility rate on the Company list February E Minimum demand 100 kW x 75 75 kW Note Because the 60 kW consumed during February is less than the 75 kW minimum the minimum demand does apply and 75 kW would be the demand for February m Demand charges 10 kW x 0 kW 65 kW x 8 45 kW 549 25 ajlaixi Fie Vew Options Widow Hep POTALTSRELSiIT ENA omamne TRANE Rate Structure Library alZi xi Aate Defirtion Deneription Notten Wisconsin Utiy Rate Unity 8 Gas Commerts Mirman charge Start penod ianusy i Oefired tates End pe od Derbe cin Electac consumption On peak Janua December em E actae demand On pask Jarumy December Piste ype On pes u Mirim demand In this example the utility charges Fwstadustnent ple y g 8 Neg Delran 0 530 therm for the first Cann Chee 0 200 therms 0 499 therm for the next 300 therms 0 485 therm for Soe a all remaining therms and a sn on customer charge of 10 00 each month regardless of usage fee Vette geome Fa Assuming that 600 therms of gas are consumed in January the charges from the utility company would be as follows January m Customer charge 10 00 E Gas usage charges
543. uch airflow for the design heating load The program tries to reduce the design supply air dry bulb for heating but cannot reduce it below the Minimum Heating Supply Air Dry Bulb Temperature or the Room Design Heating Dry Bulb Temperature To minimize the overheating remove the heating supply air dry bulb and allow the program to calculate the value s Scenario 4 Over undersizing on heating for a variable volume system with cooling supply air dry bulb entered by the user or calculated by TRACE 700 and the heating supply air dry bulb specified by the user Room 1 E Cooling Qs 11 000 Btu calculated by TRACE 700 based on heat gains E Heating Qs 5 500 Btu calculated by TRACE 700 based on heat losses E Cooling Ts 55 F Input by user or calculated by TRACE 700 E Heating Ts 100 F input by user E VAV minimum stop 50 percent of cooling supply airflow entered on Airflows tab of Create Rooms The cooling supply cfm would be calculated using the sensible heat equation The heating supply cfm would be calculated using the cooling supply cfm and the minimum stop Cooling 11 000 1 1 x SA x 75 55 SA 500 cfm Heating SA 500x 50 SA 250cfm In this scenario the over undersizing on heating would be over undersizing 7 1 x 250 x 70 100 5 500 2 750 Btu Advanced Usage and General Modeling Tips Oversizing and undersizing 6 55 Inputting the leaving cooling coil temperature w
544. uction systems i e supply airflow always equals ventilation airflow Do not use the Clg Airflow or Htg Airflow as the ventilation types Next define air distribution 2 In Create Systems select Displacement Ventilation w Chilled Ceilings as the System Type Sample scenario A displacement ventilation system Is being installed in a new school and will supply air via sidewall diffusers The displacement system will be sized to meet the ventilation load as well as the latent load in the occupied space A chilled ceiling system will meet the sensible loads of the occupied space Since both the displacement ventilation and the chilled beam system use chilled water coils a watercooled chiller will deliver cold water to each Pirra r Boone Airlla Albemarrre E ee faran ni iiho siyosi ea rangt Teriplstir Maan puppy hodan hupp Fom ferai Cong Te bee cakali as Hesira To be caiene Adaren sr baier hom room Resm ehant Fae po E Changen hy Hestra E Res Eip B Create Systema Selection Abematres System descepion ETSI Dinplacemers Vensiation wu Chiled Ceir l Win Valur imiia Woke Harrie imiia Wickes hloas aa were Ventilation CY araman erthanen VAN ain Verilen w Parie Ched Beare Qepianemerd Venian wath Gnom lucha CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 89 Displacement ventilation 3 On the Options tab click
545. ues ies Gea The Visible Transmissivity represents visible transmittance of the glass at normal incidence Do not confuse visible daylight transmittance with total solar transmittance which determines how much solar radiation is transmitted The Inside Visible Reflectivity is the fraction of visible not solar light that is reflected on the inside surface of the glazing This value is used to help calculate the luminance due to both 11The Internal Shade natural and electric lighting within a space Petane tere tA OLOW ELG x user to input the Visible General Oayighing Contols Pisom Poremeines Glae Paxameiees intemal Shade Parameters Transmissivity and the maeva 11 rece Inside Visible Reflectance of the glass and internal shade combination at normal incidence No inputs are required on this tab for the example scenario intaia hade Li Member Write Teancnretievity The Overall Visible Transmittance can be obtained by multiplying the Visible Transmittance of the shading device by the Visible Transmittance of the unshaded glass 12 When completed click OK and the Daylighting Parameters will close The second alternative can now be calculated and the effects of daylighting can be seen by comparing the output reports a 12 5 40 System Control Strategies TRACE 700 User s Manual e CDS PRMO01 EN Daylighting Additional Items 1 User defined templates are available only for the file in which they
546. uipment Evanceainen pnecocding T Ageci conderasthest Ta mieence ipype Heat rerien eneen E wap pral elinctnennns T X Al Pal weakest bena 13 Fies Cosi ma i To model the cooling and Casing pre Ce Cookers pi t 001 heating pla nts Aacooked Arcocked Waterco Waterco E E ween Piara weard rind aia g Condenser water puno 3 hs Add a water cooled aaa Pinay aad on san F leatr 002 9 chiller to the cooling plant am Boe Electic Gard ee seon Hot water pumo Eg and a boiler to the heating amp Hotwater from a boiler plus hot water gas J plant The boiler is the Ao Ga Are T recovered from a generator not only A ceuice for the satisfy the heating demand but also chiller For convenience fire the absorption chiller define it first To atugn equemert dag the dazed aqupment calagory lo the ceriya don bee CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 29 Cogeneration B Create Plants allj 4 Describe the boiler on the Heating Equipment tab Heaingpiat Hesin clare 002 E Rename plants and Conca Choose the appropriate Equpmerting Hamar boe a l ven p l equipment tags for bim n fi Eamets o na ee erae aI easy identification Se specify the full load Eai consumption of the hot baal Ten lt pas hoe O Daea water pump Enegiste 33 Percent etcem x Cony h oo For this example pick a gas fired boiler and enter 50 feet of water as the p
547. uld not be used for internal loads It simulates 100 percent of the internal loads in the building 24 hours a day which may not be what is actually occurring in the building In addition it also tells the program to take credit for the internal loads during the heating design calculation This schedule tends to lead to an underestimation of heating energy 6 40 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN No or low heating energy consumption and undersizing of the heating coils due to the internal loads meeting all or most of the heating loads To view the schedule click Schedules on the Libraries menu Here the user should be able to view the schedule and find schedules that more closely follow the actual operation of the building 3 The custom schedule s for internal loads have values greater than zero for the heating design day type This tells the program to take credit for the internal loads during the heating design calculation This tends to lead to undersizing of the heating coils and is not common design practice To view the schedule click Schedules on the Libraries menu Here the user should be able to view the schedule and the individual day types Example 3 COO Ah TA Templates Man ugly Fardhuy supei Room Deus Cooling Tobecscumed J Cooling Totecucused a a Heming tote comumes S Heating tote cacdi F i Vertistion i E isese a Type Germa Olfce Space 7 Corni Del a 1 C
548. um Ensure that the entered VAV minimum stop is not too low less than the entered ventilation rate Low minimum stops may cause insufficient airflow in heating mode and improper ventilation for VAV systems only The VAV minimum stop schedule in all of the rooms should be the schedule Available 100 The only time this schedule should be changed is for a VAV box with two minimum stop settings or for systems with morning warm up The VAV system may not 6 172 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Altering a load design file for energy analysis operate properly if any other schedule is used and heating energy may be underestimated Options tab of Create Systems Verify that any heat recovery devices economizers or evaporative cooling have been input A user may choose to ignore these items during the design calculations but they must be accurately accounted for in energy analysis calculations Fans tab of Create Systems Fan type and static pressure Verify that the fan static pressure and fan type have been input for every fan that exists on the system Without fan static pressures and fan types the program cannot calculate fan energy or fan heat pickup Fan schedule Ensure that all available fan schedules include a heating design definition that is midnight to midnight 100 percent The schedule Available 100 is an example of a fan schedule that would be acceptable If a fan is schedul
549. ummary System screen Click Options to I Tiia page M Deap miw view the reports available I System checkiuma I Design capaciy I Zone checksums Ergnecnng checks for sorting All input system s zone s and room s should appear in the Print selected system zones and rooms screen 4 Select the desired system s zone s or room s by clicking them and then click OK The program should return to the View Results screen 5 In this example only the ame pa information for the Office oe MEE system and rooms has been selected 6 When back on the View Results screen click Print to print the selected output reports or click Preview to preview the selected output reports Hote Skool the noord cones snd gyetert hor eee you pridd Hue to have Oheckeumne papita Some aytida well diplay no cones wher mens om connmched draip bo they ayali 6 180 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMO01 EN How to sort output gbXML import and export The import goXML Green Building XML feature will import data into a TRACE 700 project file based on building dimensional information exported from a CAD drawing The CAD software must have the capability of generating an XML file that meets the Green Building XML requirements such as Autodesk Building systems 2005 The generated TRACE 700 file will have the rooms defined floors walls windows and so forth Note that users have the op
550. ump head Type E5020 Hram woter cee perp Ful nad fo rw y watas 5 Next describe the chill pee ext eet e the chiller E a Ee For the equipment type Eaipmerttog Ebron rie a Tye E5104 Coorg wewer z em choose the hot water Eaupment cego W mer cooled crae a Hout enor wot dot NenEas absorption chiller created in O C Ean Steps 1 2 ion rote Ea Also specify the full load mee consumption of each pump S 6 Identify the heating plant Hoo Ea T 10 E that contains the boiler as Cooling Equipment Controls x the energy source for the apilat A Coa al Eqpaprrsrd bag Sbrponpleoe Cher anced chiller Faa Caig l mn Type Hone 7 The generator which is Fuadiccclervne x P i Purga Hora a used to satisfy electrical Pande ry 7 I loads uses the boiler loop Man chdied waste paba jal F for heat rejection r Evapmnise pasoi He To model it select the peepee Heir a G appropriate cogeneration Rejec condenser heat Heat rejecta mouere al Th rator ee ET type Ine gene Iaa selected for this example is P a gas engine that generates Pant Coniroka E Conigsaion up to 175 kW a of or a Henly atibiend wet bub atte SS New Cig Fora Copenseuston te Crepin gaa 175 Ke New Hig Plat Geceemhany hiin pume 7 Eg Type Be 2 2 CSCO mae If desired open the Cogeneration library to mas View the equipment defined there Custom mM Type c Cogeneration can be created
551. upply airflow volumes Sensible Heat Equation Q DSHP x SA x Ce Lea where Qs sensible load in the space Qs is calculated based on the input walls windows lights people and so forth Qs can be found on the Checksums report DSHP density specific heat product DSHP can be found on the Title Page report SA supply airflow SA is typically a variable but can be input at the room or system level SA can be found on the Checksums report Tim room setpoint Tm is a required input on the Rooms tab of Create Rooms T sadb supply air temperature Tsaap IS typically a variable but can be input on the Temperatures tab of Create Rooms Tsagb can be found on the Checksums report Depending on what values in the equation are known and or input TRACE 700 will calculate differently The following paragraphs discuss the different calculation scenarios If the cooling supply temperature and airflow are not specified TRACE 700 iterates to find the supply air temperature that satisfies the specified room relative humidity and thermostat 6 20 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRM001 EN Frequently asked questions setpoint Sometimes this calculation can lead to high supply air temperatures and high airflows due to proportionally low latent loads in the spaces To correct the high airflow and supply air temperature Issue the user can input a more realistic supply air temperature range minimu
552. us infiltration to that space However if room exhaust exceeds infiltration plus ventilation in that space then somewhere in the building a balancing amount of air is going to find a way in That airflow can enter the building as ventilation or as infiltration TRACE 700 requires that the user tell the program how that air is going to enter the building In addition that added airflow must be balanced with the room exhaust using the equation ventilation infiltration gt room exhaust at the space level CDS PRMOO01 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 67 Balancing airflows 6 68 Selecting a DX unit using TRACE 700 output This section discusses the steps for properly selecting DX equipment using the TRACE 700 output reports It will be assumed that no mistakes have been made in the modeling process and that all results are accurate for the building and systems Related reading Cooling Coil Heat Transfer Engineers Newsletter volume 31 number 1 The DX Refrigerant Cooling Coil Conundrum Engineers Newsletter volume 17 number 1 Sample scenario The design team has decided to use a VAV rooftop unit with a DX cooling coil to cool the proposed building TRACE 700 has been used to estimate the design load and airflows The design data will need to be input into a selection program to find an appropriate piece of equipment that meets the load and airflow requirements In this s
553. use tube erosion Under 1 ft sec can cause reduced heat transfer due to laminar fluid flow through tubes d As the fluid velocity increases the capacity of the coil and the pressure drop through the coil increase e Fin spacing typically ranges from 80 to 168 fins per ft for comfort cooling 2 In order to keep the dry bulb temperature in the space at the setpoint temperature the sensible capacity of the cooling coil must be at least equal to the sensible load calculated by CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 77 Selecting a chilled water cooling coil using TRACE 700 output TRACE 700 In order to keep the humidity level in the space at or below design conditions the latent capacity of the cooling coll must be at least equal to the latent load calculated by TRACE 700 3 If acoil that meets both the sensible and latent loads cannot be found using the input criteria from the example try removing the total capacity and inputting only the sensible capacity 4 The airflow under the Cooling Coil Selection portion of the Checksums report is a result of the psychrometric analysis performed by the program The program knows the space load sensible and total to be satisfied at every hour At the time of coll peak in this example month 7 hour 18 the program performs a psychrometric analysis to determine the required airflow and coil leaving temperature to satisfy the space load For a VAV syste
554. userinput heating dry bulb during the heating season CDS PRMOO0O1 EN TRACE 700 User s Manual System Design Options 4 47 Dedicated outdoorair systems 4 48 3 Select the control method for the unit Because the dedicated ventilation cooling coil cools the outdoor air to the cooling supply air dry bulb or the dedicated ventilation heating coil heats the outdoor air to the heating supply air dry bulb Fixed Setpoints will be used Input the Cooling and Heating Design Setpoints In this scenario 70 F should be input for the cooling supply air dry bulb and 68 F for the heating supply air dry bulb 5 Select the schedule for the coils and fan in the dedicated outdoorair unit System Design Options W Create Systems Dedicated Ventilation Akamara System description Fan Cole and DOAL Fanta Cancel Configueation Cost Hem Contrl method Front Spears 3 4 Coping Heating Deign Setpownte Cooling aeck ei derbub F Note For additional information related to the other Control Methods press F1 and click Control Method Dedo tat tn ies epee espe eee W Create Systems Dedicated Ventilation System description Fan Cols end DDAL Fan Col Coniguraion Coo Hes Control method Frond Selpr Cooling Heating Sepan Limits Supply air dey bulb high lent F E kad hier et F Cooling SA dew point high lint Crowley SA chew piant ka frat Dedesied Vendi
555. utput values Load Design and Energy m Ihe entered area of the window is larger than the entered area of the wall Glass area is subtracted from the entered wall area therefore this is not a valid input This will result in an underestimation of solar and conduction loads Load Design and Energy m The custom internal shading selected has a higher U factor and or Shading Coefficient than the glass type selected The values input for the custom shading device represent the combined U factor and SC for the glass and shading device Load Design and Energy Note The values used in the simulation are the values input for the custom internal shading device that is the values input for the glass U factor and SC are ignored unless the shading device is scheduled off or not selected mM Overhang Sample or any of the other Sample shadings has been selected for the external glass shading device Creating a custom shading device in the Library Template Editors program will result in more accurate estimations for the glass solar loads Be sure to select none if there is no overhang shading the windows Load Design and Energy CDS PRMOO1 EN TRACE 700 User s Manual Advanced Usage and General Modeling Tips 6 5 Common modeling mistakes 6 6 Internal Loads tab of Create Rooms m People types and their respective heat gains have been specified but the actual number of people entered is zero This will cause the program to neglect
556. w File Wizard Is intended to be used to quickly model buildings in TRACE 700 In this example a rectangular 15 story office building in Davenport lowa will be modeled ee TRACES T00 Open Sela Sachive Penpert Sum Exiting ens 1 T REHELAR EI TRCaG TEC TRACE few Fake Wizard Shep l 6 110 Advanced Usage and General Modeling Tips Quick building inputs via the New File Wizard ed are aizi Lookin 5 Press ea T abmRag g Titit Tit P eneege Tabor Welz tne z That EOE OF AGHA FITRCBAK TRG F Energy Taher a IBA TAG TRAC EOO E Con blend Fite tre A Hatsce Profile Bre z Traci FD tr I Seen plated L Ewein te T LEtencrial w T Trami complaned Temhra Frojem ire F Tinoriii iu EF Completed Tussrisiibak Ti F tat attr F Turisma fe cire vig Ahio JP TRAC EGO i T Tuteriaitrck Energy Tunari ai sem F TAa paiia vg 4 Fie nee v rne Ired 2 E TRACE 70 Files Cancel a H Complex T Shape Compi U Shape 4 W 7 3 Buking onertation 0 diag hon Herth 4 TRACE 700 User s Manual e CDS PRM001 EN 5 Input the dimensions percent glass and so on of the building and click Next 6 The New File Wizard closes and the TRACE 700 Project Navigator window appears The New File Wizard creates sets of templates for the spaces 5 rooms per wing the weather location should be the default weather location and the rest of the file should be blank Clic
557. well as the rejected heating load and the consumption of fuel for cogeneration To model this cogeneration example use the Library Template Editors program to add a hot water absorption chiller to the Cooling Equipment library 1 Copy one of the existing watercooled absorption chillers in the Cooling Equipment library 2 On the Options tab change the fuel type from steam to hot water Return to the Main tab to save this entry Related reading 2004 ASHRAE Handbook HVAC Systems and Equipment Chapter 7 Sample scenario A boiler provides the hot water necessary to satisfy all of the heating loads in a building The same boiler also furnishes the hot water needed to fire a two stage absorption chiller The building generator satisfies electrical loads up to 175 kW The heat it produces is applied to either the building heating load or the absorption chiller The illustrations below and on page 3 30 demonstrate how to model an HVAC design that includes cogeneration Comemerts High Ell Steam Homon MORKCSTM poling category W ater couled da Abroepnon 2 Stage Steam Menton amp Cooling Equipment Main alj j pado Hih EN Steam Horton HORE E Equoment ype E Stage Hot Water Absorption Chier ust Cooling type ibron m o If desired replace the AEE Mex chod waos resol 0 generic name and add a een brief description Then Fuel pace Heating plant j 2 ors save the new eq
558. wer Phort wizard How Cig Plord Aatcced Arcod Waterco Water lt o hehe uray chiller unitary lt u 2 a Sec Garfred ma han aor Condense water pump Primary chilled water pure Heating plants Iles Heating plare 002 Abnenatree 1 If desired rename the plant and or equipment tag vemnce Coolng plant Thermal Storage Planes Heatrejcton Ea Eqimertiog Om xi Type Cooler tower fox Cort Chiles x Equpmert category Warecookdche x Houi ambient wet bubot SS Eqamertiype 35ta Cenu 2 z Theta rage iG oe Capacity 2000 certs x Schedule Dichage 11amto Sem x Plant daccigtorn Thama bbig Piani Eipprreari Lay Ghia Hi AEN r Available for Thermal Evapa peecoding Me Storage is predefined in the Sets TRACE 700 Schedules Faja Goneriar eet Haa Pepto Spuper T R Fisject Peat to planit c library Damar kair priy Hist gert reheat toe T dehuridiic ation CDS PRMOO01 EN TRACE 700 User s Manual Cooling and Heating Plants 3 23 Thermal energy storage Specifying thermal storage at the equipment level automatically results in a plant configuration that looks similar to the one shown here Use the Library Template Editors program to view or customize existing schedules The 5 Schedule library contains both of the schedules used in this scenario E Available for Thermal Storage is an Equipment operation schedule With storage status it forces the ice maki
559. wer left hand corner and click Save m Tienes ef tem F Fritas Fr mang a a FF Taie T Sinke ca Den IT Chet Porre FD Date Type Components Cig Hag Cad al ii Demand Conmamoten E aia vee Traces FOO ve ALhdieer GACA TEE TOD Pes Exe ee TAC 00S TRACE Projects EX S 4R DONE Profile civ SS a eT ee tA ey Butt Coning Cots al Heating Cob Al Coning Cots Ai Hening Cds AI Cooling Cots Al oe Oe y O Jan we T 27 10 201 20 MI 0 00 dan Wae 50 1M 1H WN 0 00 Lak ee REE 1 67 a 1 87 THA 1w eee 24 50 1 l r A ECI 8 e a en 1 nr L C sa 5 a a a LL S E EE 50 11 46 Sia aa a tre arg 2 Se aa 9 ai as are a a a y o O a na Additional items and notes Whenever a chart or table is being viewed a temporary file is created that stores all of the data contained in the table or chart This temporary file is located in the directory where the trc file is located The filename of the temporary file is Filename_Profiles csv The Filename_Profiles csv file can be opened with any spreadsheet program and edited used for hand calculations or used to create graphs outside of TRACE 700 6 124 Advanced Usage and General Modeling Tips TRACE 700 User s Manual e CDS PRMOO01 EN Creating spreadsheets and tables from calculation results TRACE 700 Visualizer Using templates Templates are intended to help simplify and speed up th
560. x rejection Equpmertiag indeect then drect evap cooing v TRACE 700 models evaporative cooling as a Th p i g l New Equp watercooled chiller without a compressor les flart man cooking E Direct Evagcative Cooley Cod g Cookery System System 001 E Indirect Evaporative Cooling Col E Man Coolers Cod Eg Heating System System 001 la Heating plant man heating D hanti llas indeect theri drect evap cooking Rahast Cod E Peeheut Col System and associated coil load s are assigned to plants rather than to individual pieces of equipment Creating a separate plant for evaporative cooling lets you assign the direct and indirect evaporative coil loads CDS PRMOO1 EN TRACE 700 User s Manual System Design Options 4 43 Direct and indirect evaporative cooling I These illustrations from the Library Template Editors program show how TRACE 700 models staged evaporative cooling The definition for the Indirect then Direct Evap Cooling equipment type resides in the Cooling Equipment library It sets the compressor energy rate at O kW and assigns pumps that only operate when a load exists on the direct or indirect evaporative coll 4 44 System Design Options w Library Template Editors Opters window Fh Yaw slgj j POTES g2 iT Eicon ruar TRANE E Cooling Equipenenit Main Cooling category WN coded chain Comments Mesni of Incienct then Dimct rager sirm TRACE 700 User s Manual e
561. y supplying hot water to fan coils distributed throughout the building Figure 3 16 Integrated HVAC and domestic hot water systems fan coil Application considerations m All components connected to the domestic water system must be compatible with and rated for use with potable water For example use bronze pumps coppertube boilers and fan coils with lead free fittings and solder m Eliminate air from the potable water loop at the expansion tank as well as at the fan coils mM Provide appropriate water treatment Sample scenario A gas fired boiler provides hot water to satisfy the heating load for the building The same boiler also supplies 105 F water at a rate of 200 gpm to satisfy the hourly demand for domestic hot water The illustrations below demonstrate how to model a boiler 3 62 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Domestic hot water assigned to a boiler that serves two purposes comfort heating and domestic hot water Note Gallons should not be used with domestic hot water Gallons should only be used for water consumption i e makeup water Wi To represent the domestic hot water for this example create a new base utility using the Library Template Editors program Dercrtion Domene hot water iownse oneei Save Comments knered the sd iteary menor to change houby 2 Cornel 1 Copy the domestic hot Diw water member of th
562. y the engine The cost of locally generated electricity often exceeds the cost of energy from the utility and the economic advantage of cogeneration systems is therefore derived from appropriate use of the waste heat One common application is hot water for domestic or process loads Waste heat from cogeneration can also serve as an energy source for comfort heating Figure 3 6 Cogeneration system NNN s e electricity engine generator NEANG Mai poo load absorption cooling load Dq chiller Not shown cooling tower loop Application considerations m VWhen compared with conventional HVAC systems cogeneration systems are more expensive to install and require additional maintenance Consider these characteristics when determining whether cogeneration is feasible for a particular application m An absorption chiller that provides chilled water for comfort or process cooling can magnify the economic potential of waste heat from cogeneration If the cogenerator cannot produce water that is hot enough to drive the absorption cycle it may be necessary to add another heat source to raise the water temperature and serve as a backup system 3 28 Cooling and Heating Plants TRACE 700 User s Manual e CDS PRMO01 EN Cogeneration P alls TRACE 700 generates a special Cogeneration report that provides an hourly profile of the electrical and heating loads before and after cogeneration as
563. y wheel OA peecondior Sonsdit wheel UA precondtoreng Senedde wheel pasia SA lapenn Senshi rieel tams SA tempenng Sold deni on ret os deck Sobd denic on vert deck Salles energy riccwenyAranater at dation h durmenti batad off Direct efficiency E x Deect cod echeckie fE i Bgm 7 Stage 1 Atode Energy Recowerpy Transter Type Taal enaigy wha OA pssconder i Eiradedeck Symone gt Schade aven 5l alls nik Click Yes to activate energy recovery transfer for design and energy analysis Click No to ignore energy recovery transfer during the design calculation and include it only during the energy analysis simulation Note This message will only appear whenever an energy recovery transfer device is 4 added and Allow energy recovery transfer during design calculations is turned off patie J gme E Select Ventilation upstream if the device is located in the outdoor air stream and upstream of the optional ventilation coil Select Return outdoor air upstream if the device is located in the mixed air stream upstream of the main cooling coil TRACE 700 User s Manual e CDS PRM001 EN 4 Select the exhaust side Abemative 1 deck for the device In span cin SE suit Note If both stage 1 and this case the energy Evoa Crio SAEST stage 2 energy recovery from the system exhaust Lie Type i transfer devices are given tweet the same exhaus
564. zing E DSHP is the density specific heat product 1 085 at sea level For simplification purposes 1 1 is used DSHP is calculated for each weather location and can be found on the Title Page report m SA is the supply airflow This can either be input on the Airflows tab of Create Rooms or calculated by TRACE 700 using the sensible heat equation SA can be found on the Checksums report E T is the room set point temperature entered on the Rooms tab of Create Rooms We will assume 75 F for cooling and 70 F for heating E T is Supply air dry bulb SADB which is either input on the Temperatures tab of Create Systems or calculated by TRACE 700 using the sensible heat equation Ts can be found on the Checksums report If only the sensible over undersizing is considered then the over undersizing would be equal to the difference between Os and DSHP x SA x T Ts over undersizing DSHP x SA x T T Q For cooling design reports M a positive value denotes overcooling or oversizing of the cooling coll M anegative value denotes undercooling or undersizing of the cooling coil For heating design reports E a positive value denotes underheating or undersizing of the heating coil M anegative value denotes overheating or oversizing of the heating coil Seven scenarios will be used to calculate over undersizing and explain why it occurs and how to minimize it Scenario 1 Over undersizing on

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