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Carrier 38AK024-044 User's Manual

1. AMOUNT COMPRESSOR pints liters 06E4250 14 6 6 06E9265 19 9 0 06E9275 19 9 0 06E9299 19 9 0 When additional oil or a complete charge is required use only Carrier approved compressor oil Witco Chemical Corp Suniso 3GS Texaco IB 3354 44 quee EA EAS Cass Capella WF 32 Shrieve Chemical Co Zerol 150 Synthetic IMPORTANT Do not use drained oil or use oil that has been exposed to atmosphere Refer to Carrier Standard Service Techniques Manual Chapter 1 Refrigerants for procedures to add or remove oil 18 Liquid Shutoff Charging Valve is located inside the compressor compartment and is provided with 1 4 in flare connection for field charging Capacity Control is by either one or 2 suction pressure actuated unloaders Each controls 2 cylinders Unloaders are factory set see Table 1 but may be field adjusted Number I unloader is on cylinder bank on same side of compressor as terminal box CONTROL SET POINT The control set point cylinder load point is adjustable from 0 to 85 psig To adjust turn control set point adjustment nut Fig 17 clockwise to its bottom stop In this position set point is 85 psig Then turn adjustment counterclockwise to desired control set point Every full turn counterclockwise decreases set point by 7 5 psig CONTROL SET POINT ADJUSTMENT NUT A POWER HEAD PRESSURE DIFFERENTIAL ADJUSTMENT SCREW
2. D x i Ts NNECTION T 8 4 lt CTION SUCTION 801 3 1 8 LX ms MTG HOLES 6 2 DEMNM 1001 2057 63 5 3 15 16 6 9 2 1 2 DIA LIFTING 40 RENE 32471 7 8 DIA FIELD CONTROL SIDE VIEW POWER ENTRY MM EID EDS insional Drawing 38AK028 034 NOTES HINGED ACCESS DOOR 1 THERE MUST BE 1220 mm 4 Ft FOR SERVICE AND FOR UNRESTRICTED AIRFLOW ON ALL SIDES OF UNIT 2 THERE MUST BE MINIMUM 2440 mm 8 ft CLEAR AIR SPACE ABOVE UNIT 3 THE APPROXIMATE OPERATING WEIGHT OF THE UNIT IS 50 HZ amp 60 HZ WT LBS 3BAK044 1106 38AK044C 2745 1246 22 2 7 8 DIA NOTE C INDICATES COPPER COIL FIELD CONTROL CIRCUIT WIRING CONTROL BOX 2 4 63 5 92 1 2 1 2 3 5 8 DIA COMPR FIELD MAIN POWER SUPPLY SECTION COMPR SECTION 1 3 APPROX OPER WT LB AT SUPPORT POINTS sonz 1 2 3 4 Tor 2437 2745 1742 5 8 9 16 044 722 924 347 444 044C 808 995 422 520 HINGED ACCESS DOOR HINGED ACCESS DOOR A CEE RES J amp s e sa SUCTION LINE CONNECTION 2 1 8 0 0 om HIDDEN LIQUID LINE CONNECTION 22 56 SE ST EE m 7 8 0 0 UPS HIDDEN 4521 Lt 1 1 9 16 i 80 2 3 16 J f 1 8 h 2411 A 3 sve z p i 12 UE y wwe 2351 SPP aaah qd 1 1 5 8
3. VALVE BODY BYPASS PISTON RING BYPASS PISTON NG CAP CAP MUST BE REPLACED TO PREVENT REFRIGERANT LEAKAGE Fig 17 Capacity Control Valve PRESSURE DIFFERENTIAL The pressure differential difference between cylinder load and unload points is adjustable from 6 to 22 psig To adjust turn pressure differential adjustment screw Fig 17 counterclockwise to its backstop position In this position differential is 6 psig Then turn adjustment clockwise to desired pressure differ ential Every full turn clockwise increases differential by 1 5 psig Oil Pressure Safety Switch OPS in the control circuit stops the compressor and unit if proper oil pressure differential is not established at start up or maintained during operation If OPS stops the unit determine the cause and correct before restarting unit Failure to do so will constitute abuse Equipment failure due to abuse may void the Warranty Compressor Protection CIRCUIT BREAKER Calibrated trip manual reset ambient compensated magnetic breaker protects against motor overload and locked rotor conditions DISCHARGE THERMOSTAT A sensor in the dis charge gas of 06E compressor reacts to excessively high discharge gas temperature and shuts off the compressor TIME GUARDS control protects compressor against short cycling See Sequence of Operation page 16 CRANKCASE HEATER minimizes absorption of liquid refrigerant by oil in crankcase during brie
4. Power line open Oil pressure switch tripped Safety device tripped Contactor stuck open Loose terminal connection Improperly wired controls Seized compressor NOOO POM Low line voltage 9 Compressor motor defective COMPRESSOR STOPS ON LOW PRESSURE CONTROL 1 Compressor suction shutoff valve partially closed 2 Low refrigerant charge 3 Liquid line solenoid valve s fails to open COMPRESSOR STOPS ON HIGH PRESSURE CONTROL 1 Compressor discharge valve partially closed 2 Air in system 3 Condenser fan s not operating UNIT OPERATES TOO LONG OR CONTINUOUSLY 1 Low refrigerant charge 2 Control contacts fused 3 Air in system 4 Partially plugged expansion valve or filter drier SYSTEM IS NOISY 1 Piping vibration 2 Compressor noisy COMPRESSOR LOSES OIL 1 Leak in system 2 Crankcrase heaters not energized during shutdown 3 Inadequate piping FROSTED SUCTION LINE 1 Expansion valve admitting excess refrigerant HOT LIQUID LINE 1 Shortage of refrigerant due to leak 2 Expansion valve opens too wide FROSTED LIQUID LINE 1 Restricted filter drier COMPRESSOR WILL NOT UNLOAD 1 Defective unloader 2 Defective capacity control solenoid valve 3 Miswired liquid line solenoid 4 Weak broken or wrong valve body spring COMPRESSOR WILL NOT LOAD 1 Miswired capacity contro liquid solenoid 2 Defective capacity control solenoid valve 3 Plugged strainer high side
5. 1619 40 9 F 806 2 7 16 5 3 3 4 1 9 16 2 3 4 END VIEW 1001 9 1 ENY VIEW 3 15 16 3 4 DIA MOUNTING HOLES 63 5 92 1 TYP 4 PLACES 2 1 2 3 5 8 DIA 28 FIELD POWER FIEL ENTRY amp LIFTING POWE Fig 8 Dimensional Dre TOP VIEW APPROXIMATE AIRFLOW THRU DISCONNECT CONDENSER HORIZONTAL LOCATION CONDENSER COIL De 1 1 1 v NUT sees d L SUCTION arr MTG HOLES 26671 8 9 63 5 regcm LIFTING 4424 14 6 1 87 MA CONTROL SIDE VIEW ENTRY Se ing 38AK044 REMOVE BLU JUMPER 400 V ONLY EQUIP GND LLSV 346 380 IF AFS USED NEUTRAL FIELD CONTROL THERMOS TAT 24 FIELD POWER SUPPLY 22 2 7 8 DIA HOLES r es ud L NEC DISCONNECT _ 635 21 2 OR 92 1 35 8 NOTES 1 Factory wiring in accordance with National Electrical Code N E C Any field modifications or additions must be in compliance with all applicable codes 2 Ail field interlock contacts in the 115 v control circuit must have minimum rating of 180 va pilot duty plus capacity required for field installed equipment All field interlock contacts in the 24 v control circuit must have minimum rating of 70 va pilot duty plus capacity required for field installed equipment Remove wire between terminals TB2 1 and 6 when airf
6. COMPRESSOR END LEFT SIDE ACCESS DOOR OIL PRESSURE SAFETY SWITCH is reset by opening the side access door on the left side of the unit as viewed from the compressor end The liquid line service valve can be found behind the side access door on the right hand side of the unit as viewed from the compressor end CONDENSER SECTION Condenser fan motors fans can be serviced by removal of outlet grilles or side panels If a fan motor is serviced be sure the wire fan guard is in place over each fan before starting unit See Fig 16 for proper fan adjustment Tighten fan hub securely on motor shaft with setscrew which bears against the key Be sure to replace Permagum and rubber cap over end of motor shaft to protect against moisture causing fan to rust on shaft COMPRESSOR END CONTROLS PANEL REMOVED LIQUID LINE SERVICE VALVE COMPRESSOR END RIGHT SIDE ACCESS DOOR Fig 15 38AK Unit with Access Panels Removed 38AK024 Shown Fan Adjustment See Fig 16 TOP OF FAN ORIFICE FILL HOLE IN FAN HUB WITH PERMAGUM FAN BLADE HUB ORIFICE PROP LOCATION 60 Hz 38AK024 38AK028 034 38AK044 3 12 79 2 3 62 91 9 3 88 98 6 50 Hz 38AK024 3 62 91 9 3 88 98 6 38AK028 034 044 3 12 79 2 338 85 9 Fig 16 Location of Prop on Motor Shaft from Outside of Orifice Ring Oil Charge Compressors are factory charged with oil as follows
7. For example 2 solenoids may be used with 3 TX Vs one of the solenoids serving a liquid line feeding 2 of the TXVs Table 2 Refrigerant Piping Sizes SINGLE SUCTION RISERS LENGTH OF INTERCONNECTING PIPING F L Liquid Line S Suction Line IMPORTANT Requires a double suction riser see below NOTE Liquid and suction line sizes are OD in CONDENSING UNIT AX 914 mm MAXIMUM LIQUID LIFT UNIT 38AK EVAPORATOR A SUCTION RISER WITHOUT TRAP SUCTION RISER WITH TRAP C SUCTION LINE TO CONDENSING UNIT DOUBLE SUCTION RISERS LENGTH OF INTERCONNECTING PIPING F 101 200 NOTE A B C dimensions relate to reference diagram SUCTION PIPING ATEVAPORATOR AND TXV BULB LOCATION See Fig 5 The purpose of these recommendations is to achieve good mixing of the refrigerant leaving the evaporator suction header for proper sensing by the TXV bulb l A minimum of two 90 elbows must be installed Suction piping for the high velocity section should be selected for about 0 5 degree F friction loss If a 2 degree F loss is allowed for the entire suction line 1 5 degree F is left for the balance of the suction line and it should be sized on that basis Check that the high velocity sizing is adequate for oil return up the riser 2 upstream of the expansion valve bulb location The TXV sensing bulb should be located on a vertical riser where possible If a horizontal location is neces sary secur
8. HIGH PRESSURE Cutout Cutin 426 7 320 20 2206 138 Winter Start Control Switch D in the 4 function 2937 48 timer bypasses low pressure switch for 21 minutes on unit start up LOW PRESSURE 27 3 186 21 44 5 303 34 Head Pressure Control reduces condensing capacity under low ambient temperature conditions FAN CYCLING These 38AK units have standard provision for fully automatic intermediate season head pressure control through condenser fan cycling Fan no 2 is cycled by a fan cycling pressure switch FCPS which responds to variation in discharge pressure The pressure sensor is located in the liquid line of the refrigerant circuit Fan no 3 cycling is controlled by outdoor air temperature through an air temperature switch ATS 38AK044 units only The ATS is located in the lower divider panel between the compressor compartment and condenser section Through a hole in the panel the sensing element is exposed to air entering the no 1 fan compartment Fan no 1 is non cycling Table 5 shows the operating settings of the fan cycling pressure switch and the air temperature switch Table 5 Fan Cycling Controls CONTROL BY SWITCH OPENS SWITCH CLOSES 70 X 3 21 t 1 7 160 10 1103 69 Pressure psig kPa 260 15 1793 103 NOTE See Fig 6 7 8 for fan arrangement TROUBLESHOOTING SYMPTOM AND PROBABLE CAUSE COMPRESSOR DOES NOT RUN
9. 29 5 CONDENSER FANS Type Propeller Type Direct Driven No Diameter in mm 2 30 762 3 30 762 Total Airflow L s 10 600 5 000 15 700 7 400 23 700 11 200 Speed Rpm r s 950 158 CONDENSER COIL Type Horizontal Plate Fin Rows Fins in Fin Spacing mm 3 17 1 49 2 19 134 I 3 17 149 Total Face Area sq ft m2 235 2 18 39 2 3 64 584 5 43 See Service Oil Charge for Carrier approved oil NOTE Circuit breaker in main power circuit and discharge gas thermostat in control circuit Psid pounds per sq in differential 2 Placing Unit There must be 4 ft 1220 mm for service and for unrestricted airflow on all sides of unit and a minimum of 8 ft 2440 mm clear air space above unit For multiple units allow 8 ft separation between units for airflow and service Mounting Unit When unit is in proper location use of mounting holes in base rails is recommended for securing unit to supporting structure or for mounting unit on vibration isolators if required Fasteners for mounting unit are field supplied Be sure to mount unit level to ensure proper oil return to compressors Compressor Mounting As shipped compressor is held down by 4 bolts After unit is installed loosen each bolt until the snubber washer can be moved with finger pressure See Fig 3 x SNUBBER SELF OUR WASHER NEOPRENE SNUBBER COMPRESSOR FOOT ISOLATION SPRING Fig 3 Compressor Mounti
10. 4 Stuck or damaged unloader piston or piston ring s 20 oo N O N O N PROBABLE REMEDY Reset circuit breaker Reset oil pressure switch at unit Reset control circuit with thermostat Replace contactor Check connections Check and rewire Check motor winding for open or short Replace compressor if necessary Check line voltage determine location of voltage drop and remedy deficiency Check motor winding for open or short Replace compressor if necessary Open valve Add refrigerant Check liquid line solenoid valve for proper operation Replace if necessary Open valve or replace if defective Purge and evacuate system Check motor wiring and repair or replace if defective Add refrigerant Replace control Purge and evacuate system Clean or replace Support piping as required Check valve plates for valve noise Replace compressor if bearings are worn Repair leak Check wiring and relays Check heater and replace if defective Check piping for oil return Replace if necessary Adjust expansion valve Repair leak and recharge Adjust expansion valve Remove restriction or replace Replace Replace valve Rewire correctly Replace spring Rewire correctly Replace valve Clean or replace strainer Clean or replace the necessary parts Manufact
11. When dragging pull the pad Do working on the equipment observe precautions in not apply force to the unit When in final position raise the literature and on tags stickers and labels attached tothe from above to lift unit off pad equipment e Follow all safety codes Wear safety glasses and work gloves Keep quenching cloth and fire extinguisher nearby when brazing Use care in handling rigging and setting bulky equipment See Table 1 for Physical Data CAUTION All panels must be in place when rigging Do not fork ELECTRIC SHOCK HAZARD Open all remote disconnects before servicing this equipment units if no skid is supplied If unit has skid truck from sides only Manufacturer reserves the right to discontinue or change at any time specifications or designs without notice and without incurring obligations PC111 Catalog No 563 915 Printed in USA Form 38AK 1SIM Pg 1 11 89 Replaces New Tab 3a AAD 3 4 IN I9 mm NOTCHES IN END OR SPREADERS LIFTING HOLES Fig 1 Model 38AK 024 shown MODEL tb Kg 1644 521 735 2115 s80 94 2388 1092 280 711 35 2797 1207 127 3225 4o0 1245 775 1867 Fig 2 Rigging with Spreader Bars Field Supplied Table 1A Physical Data 60 Hertz UNIT 38AK x oa os o 044 COMPRESSOR Reciprocating Semi Hermetic No T
12. average voltage Maximum deviation is 4 volts Determine voltage NOTE For wire runs up to 50 ft use no 18 AWG imbalance insulated wire 35 C min For 50 to 75 ft use no 16 AWG insulated wire 35 C min For over 75 ft use 14 4 _ AWG insulated wire 35 C min as 3 Control Circuit Interlock An airflow switch may be installed in the indoor air handler to prevent unit from running when indoor air is not flowing This switch no HRS81JEO01 is available from Service Parts Center or This amount of phase imbalance is satisfactory as it is equivalentcan be field supplied This should be electri below the maximum allowable 2 cally interlocked in the control circuit between term inals 1 and 6 for flow switch on TB2 See Fig 9 for field wiring This is in the 1 15 v circuit Wires must IMPORTANT Contact your local electric utility be run in conduit with ground wire company immediately if the supply voltage phase 4 Transformer Connections See unit wiring label dia imbalance is more than 2 gram notes and 2 located behind compressor com partment end access door IMPORTANT Ensure power to the crankcase heater is always on except when servicing the unit If circuit breakers inside unit shut down the com pressor and condenser fans crankcase heater remains on HINGED ACCESS DOOR NOTES 1 THERE MUST BE 1220 mm 4 ft FOR SERVICE AND FOR UNRESTRICTED AIRFLOM ON A
13. 20 5 B B2 _stia 5 SEC 2 EEl e 40 SEC 5 r_n cr D DI lt 2 6 SEC lt 2 6SEC a awOcacvvsc D D2 ER oe 150 SEC 5 55 MINS Fig 14 Timer Cycle BLACK DENOTES CLOSED CONTACTS OMIN OR Sequence of Operation At start up the thermostat calling for cooling and all safety devices satisfied the control circuit relay CR1 closes The indoor fan motor starts imme diately With minimal demand for cooling only of the thermostat is made The timer motor starts and condenser fan no 1 starts Fan no 2 starts if high side pressure is higher than 260 psig 1793 kPa Fan no 3 38AK044 only starts if outdoor ambient rises above 80 F After a delay by Time Guard circuit of 12 seconds to approximately 8 minutes depending on the timer position the compressor starts and the primary liquid line solenoid valve opens With only TCI calling for cooling the capacity control liquid line solenoid is not energized therefore the suction pressure is such that the compressor unloads on suction pressure shortly after compressor start up The compressor operates at either 1 or 2 steps of unloading depending on the suction pressure which is in turn dependent on the evaporator load conditions As cooling demand increases TC2 of the 2 stage thermostat energizes the capacity control liquid line solenoid causing full surface of the evaporator to be active tending to raise the suction pressure
14. 38AK024 044 Air Cooled Condensing Units A ERAT ELLENUDNPSINCUSEENE UC MUEVE a T A EMEN a er ETT UR PUER UDIN Installation Start Up and Service Instructions S0 and 60 Hertz Air Cooled Packages CONTENTS Page Page SAFETY CONSIDERATIONS Charge System 11 BEFORE INSTALLATION 1 3 Operation eth e enhn 11 Rigging 1 Timer Functions 16 Placing Unit 3 Sequence of Operation 16 Mounting Unit 3 Complete Unit Stoppage 16 so aysasha die 3 SERVICE 17 19 INSTALLATION RE eda docs 3 10 Access for Servicing 17 Refrigerant Piping Connections 3 Fan Adjustment 18 Single Pumpout Control 3 Oil Charge I8 Filter Drier and Moisture Indicator 3 Liquid Shutoff Charging Valve 18 Receiver x He VR eae vostfr as adea i ee rA 3 Capacity Control 18 Piping Procedure 3 Oil Pressure Safety Switch OPS 19 Power Supply 5 Compressor Protection 19 Power W
15. 8 150 FLA Full Load Amps ICF Maximum Instantaneous Current Flow during starting the pointin the starting sequence where the sum of the LRA for the starting compressor plus the total RLA for all running compressors plus the total FLA for all running fan motors is maximum LRA Locked Rotor Amps MCA Minimum Circuit Amps complies with National Electrical Code NEC Section 430 24 MOCP Maximum Overcurrent Protection RLA Rated Load Amps Units are suitable for use on electrical systems where voltage supplied to unit terminals is not below or above listed minimum and maximum limits 1 All fans are protected by a single circuit breaker m M 3 Ph 60 Hz Min Max Supplied 3 Ph Hz in te Max MCA Fuse RLA LRA FLA ea 64 300 346 311 380 50 5 80 2044 333 200 44 COMPRESSOR m um 68 256 4 60 3 250 1740 347 173 1 0 348 4 76 9 342 263 4 44 9 259 226 0 436 223 372 4 859 366 2984 539 294 44 2560 50 0 253 5578 105 1 545 408 8 79 5 400 3510 65 4 345 ECG YE 7 4 Maximum field wire sizes allowed by lugs on terminal UNBALANCED 3 PHASE SUPPLY VOLTAGE block are Never operate a motor where a phase imbalance in supply 350 MCM for models 38AK028 208 230 3 60 voltage is greater
16. LL SIDES OF UNIT 2 THERE MUST BE MINIMUM 2440 mm 8 ft CLEAR AIR SPACE ABOVE UNIT 3 THE APPROXIMATE OPERATING WEIGHT OF THE UNIT IS 60 HZ 50 HZ WT LBS 38AK024 1456 661 38AKO24C 1580 717 Eo qo Lodel ipo Dl CoNTROL NOTE C INDICATES COPPER COIL APPROX OPER WT LB 2 4 AT SUPPORT POINTS sonz 1 2 3 4 TOT 024 411 245 1456 PBVIE 50Hz o ooo 2 53 5 92 11 2 1 2 024 587 486 358 1864 FIELD POWER SU 024c 626 518 382 1988 1 3 HING c 1130 gt i ves 3 8 1 2 7 TEE Gee Y T saw SUCTION LINE CONNECTION 1 5 8 Q D dim HIDDEN 4 3 3 4 LIQUID LINE CONNECTION l 8 0 0 O THT HIDDEN TIT i 356 T Mol TIME 1 2 2281 A 31 32 Vn psi PUN ME M 2 4 61 k 1007 E p SH 16 3 3 11 16 491 CP 1 9 16 19 1 100 3 4 DIA END VIEW 3 15 16 MOUNTING HOLES TYP 4 PLACES 63 5 92 1 22 2 2 1 27 3 5 8 DIA 7 8 DIA FIELD POWER FIELD CONTROL ENTRY amp LIFTING POWER ENTRY Fig 6 Dimensio TOP VIEW FIELD CONTROL CIRCUIT WIRING DOORS APPROXIMATE HORIZONTAL DISCONNECT CONDENSER LOCATION COIL 22 21 7 8 DIA SUCTION MTG HOLES 1880 6 2 E lt 63 5 2 1 2 DIA LIFTING 167 PT 2057 B 9 3247 10 7 13 16 SIDE VIEW I Dra
17. V 9ISd 34nss38d AINON u SAYXND A0138341 3983VH09 320038 9NILVH3dO 38 LSNW SNV4 YOOOLNO H108 T JAVA GINDIT LV 3 3301vS3dW3 GlnO 1 13 zH 09 09 Heya Buey ZL Sid 3ATVA 010011 1v 9154 55484 INOIT Ob oss ooe OSZ ooz Pd ELLA LLL LL a T JAYND 3A08V 41 393VHO QAY p HL ALI AT ONILVYSdO 38 LSNW SNV3 YOOGLNO H108 ool OOI JAWA 010017 LY 4 SYNLVYAdW3AL GINO 14 ALL OUTDOOR FANS MUST BE OPERATING 350 300 200 LIQUID PRESSURE PSIG AT LIQUID VALVE Fig 13 38AK044 Charging Chart 50 60 Hz 150 LLLTLLLLLLLNL LI FEE EEE EEE NCE LL TT ete ty tT tt iN CL BE UNE RN fea ELLELIILLLLLLLEE 120 JAVA 010017 LV 4 SYNLVYSdWAL gino 1 Timer Functions See Fig 14 1 Switch A contacts A AI and A A2 provides Time Guard Control Circuit function Start of compressor is delayed approximately 5 5 minutes after shut off The minimum time between starts of compressor is 8 minutes 2 Switch B contacts B B1 and B B2 starts compressor 3 Switch D contacts D D1 bypasses the low pressure switch LPS for 2 5 minutes at start up for winter start control TIMER POSITION DURING UNIT OPERATION EMEN 150 SEC 5 5 5 MINA KA 1 COMPRESSOR STARTS A A2 12 SEC 2 B BI e 1SEC
18. d readily acces sible from unit in compliance with NEC Article 440 14 1 Acrankcase heater is wired in the control circuit so it is always operable as long as power supply disconnect is on even if any safety device is open or unit stop start switch is off It is protected by a 5 amp circuit breaker in control power 2 The power circuit field supply disconnect should never be open except when unit is being serviced or is to be down for a prolonged period When operation is resumed crankcase heater should be energized for 24 hours before start up If unit is to be shut down for a prolonged period it is recommended that the suction and discharge valves be closed to prevent an excessive accumulation of refrigerant in the compressor oil 3 Power entry is at one end only Table 3 Electrical Data 60 HERTZ UNIT MODEL 208 230 187 254 92 1 200 380 342 418 511 600 460 414 508 46 9 100 575 518 632 42 9 024 500 208 230 187 254 200 380 342 418 028 600 460 414 508 100 5 5 518 632 500 208 230 187 254 200 380 342 418 600 460 414 508 100 575 518 632 500 230 187 254 200 380 342 418 414 508 518 632 044 UNIT 800 230 198 254 88 1 125 900 400 342 400 49 3 800 230 198 254 109 175 300 346 311 380 64 9 100 900 400 342 400 605 100 800 230 198 254 1202 200 300 346 311 380 76 1 125 900 400 342 400 68 5 110 800 230 198 254 1506 250 300 346 311 380 112 6 175 900 400 342 400 90
19. e the bulb at approximately the 4 o clock If an oil return connection at the bottom of this suction header is supplied with an evaporator this connection must be teed in ahead of first mixing elbow When the compressor is below the evaporator the riser position 3 Size the suction line from the evaporator through the riser for high velocity Enter the suction pipe sizing charts in the Carrier System Design Manual at design tons and equivalent length for 2 degree F loss If reading falls between 2 sizes on chart choose the smaller pipe size at the evaporator does not have to extend as high as the top level After a 15 diameter riser has been provided the suction line may elbow down immediately SAFETY RELIEF A fusible plug is located on unit liquid line before the liquid valve z lt Power Supply Electrical characteristics of available GENERAL WIRING NOTES power supply must agree with unit nameplate rating Supply voltage must be within limits shown in Table 3 IMPORTANT Operating unit on improper supply voltage or with excessive phase imbalance constitutes abuse and may affect Carrier warranty See Unbal anced 3 Phase Supply Voltage page 6 Power Wiring All power wiring must comply with applicable local and national codes Install field supplied branch circuit fused disconnect s per NEC National Electri cal Code of a type that can be locked OFF or OPEN Disconnect s must be within sight from an
20. f or extended shutdown periods Control circuit is maintained if com pressor fan motor circuit breakers are turned off Main disconnect must be on to energize crankcase heater IMPORTANT Never open any switch or disconnect that de energizes the crankcase heater unless unit is being serviced or is to be shut down for a prolonged period After a prolonged shutdown on a service job energize the crankcase heater for 24 hours before starting the compressor High Pressure Switch has fixed nonadjustable set tings Switch is mounted on the compressor TO CHECK Open the condenser fan circuit breaker Head pressure builds up until compressor shuts down This should be at the cutout pressure in Table 4 Close condenser fan circuit breaker After pressure drops to cut in setting reset control circuit by opening then closing the control circuit switch After control circuit is reset the Time Guard timer cycles and in approximately 5 5 minutes the com pressor restarts 19 Low Pressure Switch has fixed nonadjustable settings Switch is mounted on the compressor TO CHECK Slowly close liquid shutoff valve and allow compressor to pump down Do not allow compressor to pump down below 2 psig 13 8 kPa Compressor should shut down when suction pressure drops to cutout pressure in Table 4 and should restart when pressure builds up to cut In pressure shown Table 4 Pressure Switch Settings psig kPa
21. into compres sor crankcase Be sure crankcase is warm heater should be on for 24 hours before starting compressor 10 Be sure compressor floats freely on the mounting springs See Compressor Mounting and Fig 3 for loosening compressor bolts ON Q RU Leak Test and Dehydration Leak test the entire refrigerant system by the pressure method described in the Carrier Service Techniques Manual Chapter 1 Section 1 6 Use R 22 at approximately 25 psig backed up with an inert gas to a total pressure not to exceed 200 psig Preliminary Charge Refer to Carrier Standard Service Techniques Manual Chapter 1 Section 1 8 for charging methods and procedures Charge system with approximately 25 Ibs of R 22 by the liquid charging method and charging by weight procedure Start Unit Close field disconnect fan circuit breaker and set thermostat above ambient temperature so that there is no demand for cooling Now only the crankcase heater is energized After the heater has been on for 24 hours the unit can be started If no time has elapsed since the preliminary charge step has been completed it is unnecessary to wait the 24 hour period Close the compressor circuit breaker then reset the indoor thermostat below ambient temperature so that a call for cooling is ensured NOTE Do not use the compressor circuit breaker to start and stop compressor except in an emergency Depending on the position of the Time Guard timer start
22. iring 3 High Pressure Switch 9 START UP 11 16 Low Pressure Switch 19 Dre CK 11 Winter Start Control 19 Leak Test and Dehydration 11 Head Pressure Control 19 Preliminary Charge 11 e Start Unit z etr 11 TROUBLESHOOTING 20 SAFETY CONSIDERATIONS BEFORE INSTALLATION Installing starting up and servicing air conditioning Rigging Preferred method is with spreader bars equipment can be hazardous due to system pressures from above the unit Use 2 in 50 mm OD pipe or electrical components and equipment location roofs ele hooks in lifting holes Rig with 4 cables and spreader vated structures etc bars All panels must be in place when rigging See rigging label on unit for details concerning shipping weights distance between lifting holes center of gravity and spreader bar dimensions See Fig 2 If overhead rigging is not possible place chiller on skid or pad for rolling or dragging When rolling use Only trained qualified installers and service mechanics should install start up and service this equipment Fig 1 Untrained personnel can perform basic maintenance functions such as cleaning coils All other operations should e minimum 3 rollers
23. low switch is field installed 3 For internal unit wiring reference wiring book TB2 is 115 1 60 TB3 is 24 1 60 LEGEND AFS Airflow Switch GND Ground LLSV1 Liquid Line Solenoid Valve for Pumpout LLSV2 Liquid Line Solenoid Vaive for Capacity Control TB Terminal Block Field Power Wiring Field Control Wiring Factory Installed Wiring Fig 9 Typical Wiring Schematic 10 F v gt ms er rU ELT s M vv v START UP Initial Check CAUTION Do not attempt to start the condensing unit even mo mentarily until the following steps have been com pleted Compressor damage may result 1 Check all auxiliary components such as air handling equipment and other equipment Consult the manu facturer s instructions regarding any other equipment connected to the condensing unit If used air flow switch must be properly installed See Fig 9 2 Backseat open compressor suction and discharge valves Close valves one turn to allow pressure to reach test gages Open liquid line service valve Set thermostat Check tightness of all electrical connections Compressor oil level should be visible in sightglass See Service Oil Charge 7 Be sure unit is properly leak checked dehydrated and charged See below 8 Electrical power source must agree with nameplate rating 9 Crankcase heater must be firmly locked
24. ng INSTALLATION Refrigerant Piping Connections Line sizes depend on length of piping required between condensing unit and evaporator See Table 2 It is important to consider liquid lift and compressor oil return Refer to Part 3 of Carrier System Design Manual for line sizing information and Fig 4 for recommended piping details COIL END RED RED CENTER ELL LINE TO COMPRESSOR VIA DOUBLE SUCTION RISER IF NECESSARY UPPER SECTION AIR FLOW TXV SENSING BULB MIDDLE SECTION AIR FLOW LOWER SECTION 8 DIAM MIN TYP XV EQUALIZER CONNECTION NOTES 1 Suction line is connected to coil on same side as the entering air 2 Forcoilshaving only one section use upper section piping for coils having 2 sections use upper and middle section piping 3 Lower section is first on and last off 4 For more complete piping information refer to Carrier System Design Manual Part 3 Fig 4 Suction Line Piping to Unit with 3 Section Coil Split Single Pumpout Control All units are factory wired to operate on single pumpout control A factory supplied liquid line solenoid valve must be installed in the liquid line ahead of the indoor coil See Fig 5 Wires from solenoid valve must be in conduit and a ground wire must be provided to comply with codes WARNING Failure to properly install liquid line solenoid at the indoor unit as described without Carrier author ization may VOID war
25. or fans continue to run It stays locked out for 5 5 minutes until the timer motor comes back to 0 time see Fig 14 At 0 time the LPS is jumpered winter start control It remains jumpered for 2 5 minutes Because the LPS is jumpered the com pressor restarts and runs for the 2 5 minute time period At the end of this 2 5 minutes if the LPS has still not closed the compressor is again locked out The timer motor is de energized and cannot restart until the LPS closes The outdoor fans continue to run as long as there is a call for cooling Automatic reset of the LPS causes the timer to recycle so that the compressor can start If sufficient compressor oil pressure has not been built within 2 5 minutes after the compressor starts the unit is completely de energized until the OPS is manually reset at the unit A CAUTION If unit or circuit stoppage occurs more than once due to any safety device the trouble should be corrected before any attempt to restart SERVICE CAUTION Turn off all power to unit before proceeding Access for Servicing See Fig 15 COMPRESSOR SECTION The compressor compart ment has 2 side doors and one front door for servicing providing access to compressor all components of the refrigeration system electrical controls and control box After opening front door an inner cover must be removed for access to control box COMPRESSOR END AND RIGHT SIDE VIEW OIL PRESSURE SWITCH
26. ranty If unit is used with a chiller wiring modifications may be required Filter Drier And Moisture Indicator Every unit should have a filter drier and a sight glass moisture indicator field installed Select the filter drier for maximum unit capacity and minimum pressure drop Figure 5 shows recommended locations of filter drier s and sight glass Complete the refrigerant piping from the evaporator to the condenser before opening the liquid and suction lines at the condensing unit One filter drier may be installed at location A in Fig 5 or 2 filter driers may be installed at locations B FACTORY SUPPLIED FIELD SUPPLIED SOLENOID VALVE CAPACITY CONTROL SIGHT SOLENOID VALVE 2 FILTER DRIERS FILTER DRIER B LOCATIONS A LOCATION INDOOR EVAPORATOR L COI CIRCUIT 2 DISTRIBUTOR Fig 5 Liquid Line Solenoid Valve Filter Drier s and Sight Glass Locations Receiver No receiver is provided with the unit it is recommended that one not be used Piping Procedure Do not remove run around pipe from suction and liquid line stubs until piping connections are ready to be made Pass nitrogen or other inert gas through piping while brazing to prevent formation of copper oxide Install field supplied thermostatic expansion valve in liquid line ahead of each evaporator section For 2 step cooling the field supplied solenoid used must be wired to be opened by control from a 2 step thermostat
27. so that the compressor loads 16 A pump out relay POR in the control circuit is energized when thermostat contacts make A set of normally open POR contacts close completing a compressor control circuit which bypasses the contacts As cooling demand is satisfied the thermostat contacts break de energizing CR1 The LLS valve closes stopping the flow of liquid refrigerant to the evaporator and subsequent suction gas to the compressor The compressor continues to operate because of the CRI bypass with relay TRI With no refrigerant returning to the compressor low side pumpout takes place and the compressor shuts down on low pressure control The compressor does not restart until the thermo stat again calls for cooling Complete Unit Stoppage CAUSES Interruption of supplied power open discharge gas thermostat DGT compressor overtemperature pro tection or open high pressure safety switch causes com pressor stoppage RESTART The unit recycles and restarts automatically under the Time Guard device when power is restored Stoppage by DGT HPS or compressor circuit breaker requires manual resetting of the control circuit To restart the Time Guard timer when DGT or HPS are tripped merely open and then close the thermostat contacts It is necessary to manually reset the compressor circuit breaker at the unit If LPS is not closed within 2 5 minutes after compressor starts the compressor locks out and the outdo
28. than 2 Use the following formula to 38AK034 208 230 3 60 230 3 50 and determine the voltage imbalance 38AK044 208 230 3 60 230 3 50 2 0 AWG for all other models 5 Terminals for field power supply are suitable for copper copper clad aluminum or aluminum conduc 96 Voltage Imbalance max voltage deviation from average voltage tors Insulation must be rated 167 F 75 C minimum average voltage CONDENSER FANS The fans must rotate counter clockwise when viewed from above If necessary correct Example Supply voltage is 240 3 60 direction of fan rotation by interchanging any 2 power input wires at disconnect switch Affix crankcase B C AB 243 volts decal located in installer s packet to unit disconnect switch BC 236 volts AC 238 volts FIELD CONNECTIONS 1 Main Power Bring wires from the fused disconnect switch through hole in bottom rail of unit to control Average Voltage box Fig 6 7 8 and connect terminals line side of terminal block see Fig 9 To comply with NEC Article 440 14 the disconnect Ee within sight from and readily acces AB 243 239 4 volts 239 236 3 volts 2 24 v Control Power Units have single point power AC 239 238 1 volt connections Control circuit is directly connected inter nally to unit Maximum 24 v control circuit is 3 amps 243 236 238 239 volts 3 Determine maximum deviation from
29. up of the compressor occurs within 12 seconds and 8 minutes from the time the control circuit is energized Charge System Actual start up should be done only under supervision of a qualified refrigeration mechanic Refer to charging charts See Fig 10 through 13 for the particular unit being charged Measure pressure at the liquid line service valve being sure a Schrader depressure is used if required Also measure liquid line temperature as close to the liquid service valve as possible Add charge until the pressure and temperature conditions of the charging chart curve are met If liquid pressure and temperature point fall below curve add charge If liquid pressure and temperature point fall below curve reduce the charge until the conditions match the curve A CAUTION Never charge liquid into the low pressure side of system Do not overcharge During charging or removal of refrigerant be sure indoor fan system is operating Operation Refer to control circuit diagram on the unit or in the unit wiring book o ZH 09 08 Heyg Buibieyd pZONVSE OL Bly JAVA 010017 1v 9154 34nSS38d GINOIT Ov ose oog 00 OGI 10161 OG Ba O9 d MO 138 3 3943 VH 3901034 P d Pd pea ot 3AMn2 3A08V J39Y YH QGV 9NILVH3dO 38 LSNW SNVA YOOGLNO H108 3A1VA gI n0 1 Lv 4 19834 WIL AINON 12 d zH 09 09 gzoxXvse LL 614 JAVA 017017 L
30. urer reserves the right to discontinue or change at any time specifications or designs without notice and without incurring obligations Book E PC111 Catalog No 563 915 Printed in USA Form 38AK 1SIM Pg 21 11 89 Replaces New Tab a 77 TW
31. wing 38AK024 NOTES HINGED A 1 THERE MUST BE 1220 mm 4 ft FOR SERVICE AND FOR UNRESTRICTED AIRFLOW ON ALL SIDES OF UNIT 2 THERE MUST BE MINIMUM 2440 mm B ft CLEAR AIR SPACE ABOVE UNIT 3 THE APPROXIMATE OPERATING WEIGHT OF THE UNIT IS 60 HZ UNIT WT LBST WT KG 38AK028 1650 38AKO28C 1804 38AK034 1803 38AK034C 2 4 COMPR SECTIO 1 3 NOTE C INDICATES COPPER COIL 22 2 7 8 50 HZ FIELD CONTROL CI 83 5 92 1 2 1 2 3 FIELD MAIN POWER 38AK034C 2009 911 APPROX OPER WT LB AT SUPPORT POINTS CONTRC sonz i 2 7 3 4 ror 418 626 242 364 462 666 276 400 459 673 272 399 034C 518 719 323 449 590 507 590 506 542 632 541 628 538 628 538 683 586 683 586 1742 5 8 9 16 HINGED ACCESS DOOR 61 2 16 19 1 3 4 DIA MOUNTING HOLES TYP 4 PLACES T I 1315 4 3 3 4 SUCTION LINE 1 5 8 0 0 2 1 8 0 0 HIDDEN LIQUID LINE CO 7 8 0 0 HIDDEN 9 2413 344 1 2 1 1 9 16 235 9 1 4 1619 5 3 3 4 d END VIEW 53 5 92 1 2 1 2 3 5 8 DIA FIELD POWER ENTRY amp LIFTING Fig 7 Dir 155 DOOR DIA UIT WIRING 8 DIA PLY BOX COMPR SECTION TOP VIEW AIRFLOW THRU APPROXIMATE CONDENSER HORIZONTAL DISCONNECT CONDENSER LOCATION COIL R A A A Tra a ET
32. ype 1 06E4250 1 OGE9265 1 1 06E9275 1 06E9299 No Cyls ea Speed Rpm r s 4 1750 29 6 1750 29 Capacity Steps 2 3 Oil Charge Pt L 14 66 19 9 Oil Pressure Switch Setting psid 9 Crankcase Heater watts 180 Protection See Note Capacity Control Suction Pressure Unloader s No 1 Unloader Settings psig Load 76 76 76 76 Unload 58 58 58 58 No 2 Unloader Settings psig Load 78 78 78 Unload 60 60 60 REFRIGERANT CHG R 22 CONDENSER FANS Type Propeller Type Direct Driven No Diameter in mm 2 30 762 3 30 762 Total Airflow Cfm L s 10 600 5 000 15 700 7 400 23 700 11 200 Speed Rpm r s 1140 19 CONDENSER COIL Type Horizontal Plate Fin Rows Fins in Fin Spacing mm 3 17 149 2 19 134 3 17 149 Total Face Area sq ft m 235 218 392 364 58 4 5 43 Table 1B Physical Data 50 Hertz UNIT 38AK COMPRESSOR Reciprocating Semi Hermetic No Type 1 06E4250 1 06E9265 1 06 9275 1 06 9299 No Cyls Speed Rpm r s 4 1450 24 2 6 1450 24 2 Capacity Steps 2 3 Oil Charge Pt L 14 66 19 9 Oil Pressure Switch Setting psid 9 Crankcase Heater watts 180 Protection See Note Capacity Control Suction Pressure Unloader s No 1 Unloader Settings psig Load 76 76 76 76 Unload 58 58 58 58 No 2 i Unloader Settings psig Load 78 78 78 Unload 60 60 60 REFRIGERANT CHG R 22 Approximate Ib kg 28 127 30 5 13 8 435 19 7 65

Carrier 38AK024-044 User's Manual

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