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Lennox HP29 7.5-10 ton

1. GROUND LENNOXe HEAT PUMP OUTDOOR UNITS NOTE USE COPPER HP29 090 2 G J M Y CONDUCTORS IF ANY WIRE IN THIS APPLIANCE IS REPACED ONLY IT MUST BE REPLACED WITH WIRE OF LIKE SIZE RATING AND INSULATION THICKNESS HEAT PUMP SECTION B4 WARNING Supersedes ELECTRIC SHOCK HAZARD CAN CAUSE INJURY 100 OR DEATH UNIT MUST BE GROUNDED IN ACCORDANCE WITH NATIONAL AND LOCAL CODES New Form No 535 542W 2000 Lennox Industries Inc Litho U S A Page 20 B HP29 090 3 Y G J M IL _ ECONOMIZER _ SLOWER __ BLOWER G _ W HEAT I WI M il MEL yir HEAT 2 W2 c ES Se RTI3 AN COOL _ Lt ER J 575 60 3 jM 1380 420 50 3 WHEN K46 IS USED CONNECT K58 1 CONTACTS AS SHOWN WITH A46 HOOK UP M VOLTAGE UNITS ONLY REFER TO UNIT RATING PLATE FOR MINIMUM CIRCUIT AMPACITY AND MAXIMUM OVERCURRENT PROTECTION WITH 511 4 K58 ON OFF FAN LOW AMBIENT CONTROL 24V COMMON Su OMEN hH cw _ DENOTES OPTIONAL AX WITH M6 VARIABLE FAN LOW A COMPONENT CONNECTIONS PRIMARY 24 VOLT TRANSFORMER MUST BE PHASED WITH B4 FAN MOTOR EXAMPLE IF MOTOR IS HOOKED TO LI amp
2. A FACTORY INSTALLED OPTION 10 _ A VOLTAGE UNITS ONLY COMMON COMMON REFER TO UNIT RATING PLATE FOR ZX MINIMUM CIRCUIT AMPACITY AND 3 MAXIMUM OVERCURRENT PROTECTION SIZE A WITH SII amp K58 ON OFF FAN LOW AMBIENT CONTROL COM 24V COMMON 24V COMMON DENOTES OPTIONAL COMPONENT CONNECTIONS A WITH A46 VARIABLE FAN LOW CONTROL QUIDOOR FAN AMBIENT CONTROL COMPRESSOR Ay PRIMARY OF 24 VOLT TRANSFORMER MOTOR QUIDOOR FAN 1 MUST BE PHASED WITH B4 FAN MOTOR ICAPACTIOR QUIDOOR FAN EXAMPLE IF MOTOR IS HOOKED TO TIMER DEFROST COMPRESSOR LI amp L5 TRANSFORMER PRIMARY HEATER COMPRESSOR MUST ALSO HOOKED ACROSS JACK GFI RECEPTACLE LI amp L JACK TEST COOL ZX WHEN K46 IS USED CONNECT CONTACTOR COMPRESSOR 1 K58 1 CONTACTS AS SHOWN RELAY DEFROST 1 WITH A46 HOOK UP RELAY LATCH DISCONNECT RELAY TRANSFER DESCRIPTION POWER BEFO RELAY OUTDOOR FAN KEY COMPONENT 55 SWITCH DEFR0ST SERVICING RELAY LOW AMB KIT 511 SWITCH LOW PRESS LOW AMB KIT 524 SWITCH LOSS CHARGE 545 SWITCH DEFROST TERMINATION SENSOR AMBIENT 548 SWITCH DISCONNECT SWITCH LIMIT HI PRESS COMP 132 TRANSFORMER HOFFMEN CONTROL IHERMOSTAT DISCHARGE LINE 2814 TERMINAL STRIP CLASS II VOLTAGE
3. timing jumper timing O FIGURE 11 Page 11 Defrost Control Production February 2006 and later Figure 12 Defrost Control The defrost control board includes the combined functions of a time temperature defrost control defrost relay diag nostic LEDs and terminal strip for field wiring connections The control provides automatic switching from normal heating operation to defrost mode and back During com pressor cycle call for defrost the control accumulates compressor run times at 30 60 or 90 minute field ad justable intervals If the defrost thermostat is closed when the selected compressor run time interval ends the defrost relay is energized and defrost begins Defrost Control Board PI FAN FIELD SELECT _ in 5 TIMING PINS Ba awu TEST PINS OX DIAGNOSTIC LEDS COMPRESSOR DELAY PINS REVERSING VALVE 24V TERMINAL STRIP CONNECTIONS DEFROST THERMOSTAT S4 K3 RELAY HIGH PRESSURE SWITCH sTsIsIsIsIsIs P6 TST PS DF C R O YI FIGURE 12 Defrost Control Timing Pins Each timing pin selection provides a different accumu lated compressor run time period for one defrost cycle This time period must occur before a def
4. LENNOX UNIT INFORMATION HP29 Corp 0101 L1 Heat Pumps 7 5 amp 10 Ton 26 4 amp 35 2 kw Service Literature Revised 02 2006 Litho U S A k ir sss t sssssYvsssvs ssssss HP29 HEAT PUMP SERIES The HP29 7 5 and 10 26 4 and 35 2 kW ton heat pump units are designated for light commercial applications with a remotely located blower coil unit or a furnace with an add on evaporator coil HP29 model units are equipped with a scroll compressor The HP29 heat pumps match with the CB CBH17 blower coil units All HP29 units are three phase This manual is divided into sections which discuss the ma jor components refrigerant system charging procedure maintenance and operation sequence Information in this manual is intended for qualified service technicians only All specifications are subject to change Procedures in this manual are presented as recommenda tions only and do not supersede or replace local or state D codes 900 29 090 A WARNING Improper installation adjustment alteration ser vice or maintenance can cause property damage personal injury or loss of life Installation and service Refrigerant can be harmful if it is inhaled Refriger ant must be used and recovered responsibly Failure to follow this warning may result in person must be performed by a qualified installer or service alinjury or death agency TABLE of CONTENTS Introduction Page 1 IV CH
5. The low ambient switch is an auto reset SPST N O pres sure switch which allows for mechanical cooling operation at low outdoor temperatures All HP29 units are equipped with S11 The switch is located in the liquid line In all HP29 units S11 is wired in series with fan relay K10 When liquid pressure rises to 275 10 psig 1896 69 kPa the switch closes and the condenser fan is energized When the dis charge pressure drops to 150 10 psig 1034 69 kPa the switch opens and the condenser fan is de energized This intermittent fan operation results in higher evaporat ing temperature allowing the system to operate without ic ing the evaporator coil and losing capacity Page 8 5 Discharge Line Thermostat S5 S5 is an automatic reset SPST N C switch which opens on a temperature rise The switch is located on the discharge line and wired in series with the CMCI board and S4 pres sure switch When discharge line temperature rises to 275 5 F the switch opens and the compressor is de en ergized through the CMCI The switch automatically resets when discharge temperature drops to 225 5 F 6 Loss of Charge Switch S24 The loss of charge switch is an auto reset SPST N O switch which opens on pressure drop The switch is lo cated on the liquid line and is wired in line to the defrost control board CMC1 See unit diagram When liquid pres sure drops to 25 5 psig 172 34 kPa the switch opens and the compressor
6. stat will close and activate the service light when discharge line temperature drops below 110 F 5 during compres sor operation The light informs the home owner of a prob lem with the system specifically the compressor When the light is second stage heating may be initiated normally closed thermostat will open when discharge line reaches 130 F 5 which requires 30 to 40 seconds of compressor operation at which time the service light is de energized Page 10 DEFROST CONTROL BOARD HP29 2 UNITS COMPRESSOR CONNECTIONS FAN DIAGNOSTIC LEDs DEFROST INTERVAL z F mune PINS PRESSURE SWITCH MEE SAFETY CIRCUIT CONNECTIONS 9 9 AMBIENT THERMISTOR CONNECTION 24V TERMINAL STRIP CONNECTIONS SERVICE LIGHT CONNECTION DEFROST SWITCH CONNECTIONS REVERSING VALVE service lights KI RELAY K2 RELAY ambient thermistor connection pressure switches 24V terminal diagnostic LEDs
7. trols operation of the reversing valve and is controlled indi rectly by the indoor thermostat The combined operation of latch relay K6 and transfer relay K8 allows the HP29 heat pumps to use a conventional heat cool thermo stat instead of a heat pump thermostat A latch relay figure 5 has two coils a SET coil and a RESET coil When 24VAC is applied to the SET coil the normally open contacts close and the normally closed con tacts open When power is removed from the SET coil nothing happens the NO contacts remain closed and the N C contacts remain open The contacts do not return to their normal position until the RESET coil is energized Once the contacts are reset they remain in their normal position when power is removed HP29 units use a DPDT latch relay Each set of nor mally open contacts con LATCH RELAY K6 trols a reversing valve When the SET coil is en ergized the normally open contacts close to energize the reversing valve there by placing the unit in the cooling mode When pow er is removed from the SET coil such as when thermostat demand is satis fied the normally open contacts remain closed the reversing valve remains en FIGURE 5 ergized and the unit re mains in the cooling mode When a heating demand is initiated the RESET coil is energized The normally open contacts open and the re versing valve is de energized thereby placi
8. General Model No HP29 090 3 HP29 120 3 Data Line voltage data 60 hz 3 phase 208 230 460v 575v 208 230v 460v 575v Rec max fuse circuit breaker size amps 60 35 25 80 40 25 TMinimum circuit ampacity 40 21 16 53 25 18 Compressor 1 Rated load amps Locked rotor amps Outdoor Coil Full load amps total Fan Motor 1 phase Locked rotor amps total TRefer to National or Canadian Electrical Code manual to determine wire fuse and disconnect size requirements NOTE Extremes of operating range are plus and minus 10 of line voltage 1HACR type under 100 amps U S only Page 3 HP29 090 3 MODEL PARTS ARRANGEMENT control box vapor line service valve defrost thermostat S6 discharge line thermostat 55 compressor B1 liquid line service valve control box defrost thermostat S6 S124 not shown low ambient switch S11 loss of charge switch liquid line service valve fan guard Z Q C 2 2 FIGURE 2 Page 4 outdoor fan B4 reversing valve high pressure switch defrost pressure switch S46 outdoor fans reversing compressor B1 HP29 090 3 CONTROL BOX e low ambient kit relay K58 defrost relay K4 latch relay 61 65 K6 Q capacitor C1 terminal st
9. L5 TRANSFORMER PRIMARY MUST ALSO BE HOOKED ACROSS 9 Y IRELAY LATCH DISCONNECT ALL K RELAY OU AN M K58 L RELAY LOW AMB KIT SERVICING P VALVE REVERSING PLUG TEST COO S24 SWITCH LOSS OF CHARGE PS JPLUC ELOWES S ISWITGH T TERMINATION RTIS SENSOR AMBIENT E32 TTRANSFO FEMEN CONTROL LIBI4 ITERI CLA 0 AG HEAT PUMP OUTDOOR UNITS HP29 090 3 G J M Y HEAT PUMP SECTION B4 IF ANY WIRE IN THIS APPLIANCE IS REPACED IT MUST BE REPLACED WITH WIRE OF LIKE SIZE RATING AND INSULATION THICKNESS 0702 WARNING ELECTRIC SHOCK HAZARD CAN CAUSE INJURY New Form No OR DEATH UNIT MUST BE ACCORDANCE WITH NATIONAL AND LOCAL CODES 534 018W 2002 Lennox Industries Inc Lithe U S A Page 21 C HP29 090 Y G J M Production February 2006 and later 12 HEAT _ HEAT 2 W2 20 _ WHEN 46 IS USED K58 1 CONTACTS AS SHOWN WITH A46 HOOK UP M VOLTAGE UNITS ONLY REFER TO UNIT RATING PLATE FOR MINIMUM CIRCUIT AMPACITY AND OVERCURRENT PROTECTION WITH 511 4 K58 ON OFF LOW AMBIENT CONTROL 24V COMMON ic DENOTES OPTIONAL DESCRIPTIO WITH_A46 VARIABLE FAN LOW COMPONENT CONNECTIONS i CONTROL PRIMARY OF 24 VOLT TRANSFORMER MUST BE PHASED WITH B4 FAN MOTOR EXAMPLE IF MOTOR IS HOOKED TO LI amp L5 TRANSFORMER PRIMARY MUST ALSO BE HOOKE
10. and indoor heat relay are energized Outdoor fan is de energized Defrost continues until 14 1 minutes have elapsed or until S46 defrost pressure switch opens When defrost pressure switch opens to terminate defrost the defrost timer loses power and resets Defrost timing is stopped until the next call for defrost when defrost thermostat closes D HP29 120 2 Y G J M 24V POWER ECONOMIZER BLOWER G BLOWER i WI HEAT WI OF HEAT 2 W2 K58 COOL I YI ONO P36 J38 FARGO DEFROST L CONTROL eh E FAN DESIGNATION VOLTAGE O Y OUT 208 230 60 3 S4 IO 6 460 60 5 575 60 3 580 420 50 5 A 972151251215 lt 020 COMMON COMMON DENOTES OPTIONAL DESCRIPTION COMPONENT CONNECTIONS COMPONENT COMPRESSOR MOTOR OUTDOOR FAN MOTOR OUTDOOR FAN 2 OR OUTDOOR FAN APA OR OUTDOOR FAN TIMER DEFROST COMPRESSOR 1 HEATER COMPRESSOR 1 JACK GF I RECEPTACLE JACK TEST COOL CONTACTOR COMPRESSOR RELAY DEFROST RELAY LATCH RELAY TRANSFER RELAY OUTDOOR FAN RELAY LOW AMB KIT RELAY OUTDOOR FAN 2 C2 VALVE REVERSING PLUG TEST COOL A FACTORY INSTALLED OPTION SWITCH LIMIT HI PRESS COMP 1 THERMOSTAT DISCHARGE LINE REFER TO UNIT RATING PLATE FOR SWITCH DEFROST MINIMUM CIRCUIT AMPACITY AND SWITCH LOW PRESS LOW AMB KIT MAXIMUM OVERCURRENT PROTECTION SWITCH LOSS OF CHARGE THERMOSTAT AMBIENT KIT
11. Check voltage supply at the disconnect switch The voltage must be within range listed on unit nameplate If not do not start equipment until the power company has been consulted and the voltage condition cor rected 5 Setthermostat for a cooling demand turn on power to blower and close heat pump unit disconnect switch to start 6 Recheck unit voltage with unit running Power must be within range shown on unit nameplate Check amper age draw of unit Refer to unit nameplate for correct running amps Three Phase Compressor Rotation Three phase scroll compressors must be phased se quentially to ensure that the compressor rotates and operates correctly When the compressor starts a rise in discharge and drop in suction pressures indicate proper compressor phasing and operation If dis charge and suction pressures do not perform normal ly follow the steps below to correctly phase in the unit 1 Disconnect the power to the unit 2 Reverse any two field power leads to the unit 3 Reconnect the power to the unit The discharge and suction pressures should operate with in their normal start up ranges NOTE The compressors noise level will be significantly higher when the phasing is incorrect The compressor will not provide cooling when the unit is not correctly phased Continued backward operation of the compressor to due to incorrect phasing will cause the compressor to cycle on in ternal protector IV CHARGING HP
12. F 4 F 1 7 C 2 2 C the switch closes initiating defrost after minimum run time of 30 60 or 90 minutes When the temperature rises to 60 F 5 F 15 6 C 2 8 C the switch opens Defrost Pressure Switch S46 Defrost switch S46 is an auto reset SPST N C pressure switch which opens on pressure rise of 275 10 psi 1896 69 kPa When S46 opens defrost operation ends The switch will reset when the unit receives a heat call and pressure falls to 195 10 psi 1344 69 kPa All HP29 units are equipped with this switch located on the dis charge line See figures 1 and 2 S46 is wired through the K8 transfer relay to the defrost board CMC1 Defrost Relay K4 Defrost relay K4 controls defrost in the HP29 units K4 is controlled by defrost board CMC1 and defrost pressure switch S46 When K4 is energized contacts close and de frost is initiated Defrost Control Production through January 2006 The defrost control board combines functions of a time temperature initiated and time pressure terminated defrost control defrost relay time delay diagnostic LEDs and field connection terminal strip See figures 10 and 11 The control provides automatic switching from normal heating operation to defrost mode and back During com pressor cycle call for defrost the control accumulates compressor run times at 30 60 or 90 minute field adjust able intervals If the defrost thermostat remains closed when the accumulated compresso
13. adjustable wrench 2 Using service wrench and 5 16 hex head extension part 49A71 back the stem out counterclockwise until the valve stem just touches the retaining ring Make sure wrench fits properly to avoid stripping stem 3 Replace stem cap Tighten finger tight then tighten an additional 1 6 turn Page 14 DANGER Do not attempt to backseat this valve past the retaining ring Attempts to backseat this valve past the retaining ring will cause snap ring to explode from valve body under pressure of refrigerant Personal injury and unit damage will result To Close Liquid Line Service Valve 1 Remove stem cap with an adjustable wrench 2 Using service wrench and 5 16 hex head extension part 49 71 turn stem clockwise to seat the valve Tighten firmly 3 Replace stem cap Tighten finger tight then tighten an additional 1 6 turn 2 Vapor Line Service Valve HP29 units are equipped with a full service ball valve shown in figure 15 The valve has one service port that contains a valve core A cap is provided to seal off the port and prevent contamination Different manufacturers of valves may be used All vapor line service valves function the same way differences are in construction If a valve fails it must be replaced To Access Service Port 1 Remove service port cap with an adjustable wrench 2 Connect gauge to the service port 3 When testing is completed replace service port cap Tight
14. figure 6 The scrolls are located in the top of the compressor can and the motor is located in the bottom of the com pressor can The oil level FIGURE 6 is immediately below the motor and oil is pressure fed to the moving parts of the compressor The lower portion of the compressor shell is exposed to low side pressure while only the very top of the shell is exposed to high side pressure The scroll is a simple compression concept centered around the unique spiral shape of the scroll and its inherent properties Figure 7 shows the basic scroll form Two iden tical scrolls are mated together forming concentric spiral shapes figure 9 One scroll remains station ary while the other is al lowed to orbit figure 8 1 Note that the orbit ing scroll does not rotate or turn but merely orbits the stationary scroll FIGURE 7 SUCTION p Z SUCTION ORBITING SCROLL STATIONARY SCROLL SUCTION 2 9 INTERMEDIATE PRESSURE GAS CRECENT SHAPED GAS POCKET POCKET FLANKS SEALED 7 BY CENTRIFIGUAL FORCE SUCTION SUCTION 3 gt MOVEMENT OF ORBIT HIGH PRESURE GAS DISCHARGE POCKET FIGURE 8 The counterclockwise orbiting scroll draws gas into the outer crescent shaped gas pocket created by the two scrolls figure 8 2 The centrifugal action of the orbiting scroll seals off the flanks of the scrolls figure 8 3 As the orbiting motion continues the gas is forced toward the cen ter of
15. the HP29 units All condenser fans have single phase motors The HP29 090 units are equipped with a single condenser fan The HP29 120 is equipped with two fans The fan assembly may be removed for servicing by removing the motor mounts nuts Page 9 C Defrost System ELECTROSTATIC DISCHARGE ESD Precautions and Procedures CAUTION Electrostatic discharge can affect electronic components Take precautions during unit instal lation and service to protect the unit s electronic controls Precautions will help to avoid control exposure to electrostatic discharge by putting the unit the control and the technician at the same electrostatic potential Neutralize electro static charge by touching hand and all tools unpainted unit surface before performing any service procedure The defrost system includes four components a defrost thermostat defrost pressure switch defrost relay and de frost control board see figures 10 11 and 12 Defrost Thermostat Switch S6 124 Defrost thermostat switches S6 refrigeration circuit one and 124 refrigeration circuit two are S P S T N O con tacts which close on temperature fall initiating defrost after minimum run time of 30 60 or 90 minutes The switches are located on each of the expansion valve distributor as semblies The switches monitor the outdoor coil saturation temperature to determine when defrost is needed When the outdoor coil temperature falls to 35
16. the pump on and continue to evacuate the line set indoor unit and outdoor until the absolute pressure does not rise above 5mm of mercury within a 20 min ute period after shutting off the vacuum pump and closing the manifold gauge valves Depending on the equipment used to determine the vacuum level absolute pressure of 5mm of mercury is equal to 500 microns When the absolute pressure requirement above has been met disconnect the manifold hose from the vacu um pump and connect it to an upright bottle of R 22 re frigerant Open the manifold gauge valves to break the vacuum in the line set and indoor unit Close manifold gauge valves and shut off R 22 bottle and remove man ifold gauge set C Charging If the system is completely void of refrigerant the recom mended and most accurate method of charging is to weigh the refrigerant into the unit according to table 4 If weighing facilities are not available or if unit is just low on charge the following procedure applies The following procedures are intended as a general guide for use with expansion valve systems only For best results indoor temperature should be between 70 F 21 C and 80 F 26 6 C Outdoor temperature should be 60 F 15 5 C or above Slight variations in charging temperature and pressure should be ex pected Large variations may indicate a need for further servicing A IMPORTANT Use tables 6 and 7 as a general guide for performing main
17. vacuum gauge to the center port of the manifold gauge set 3 Open both manifold valves and start vacuum pump 4 Evacuate the line set indoor unit and outdoor unit to an absolute pressure of 23mm of mercury or approxi mately 1 inch of mercury During the early stages of evacuation it is desirable to close the manifold gauge valve at least once to determine if there is a rapid rise in absolute pressure A rapid rise in pressure indicates a relatively large leak If this occurs the leak testing procedure must be repeated after the leak is repaired Page 17 NOTE The term absolute pressure means the total actual pressure within a given volume or system above the absolute zero of pressure Absolute pres sure in a vacuum is equal to atmospheric pressure mi nus vacuum pressure When the absolute pressure reaches 23mm of mercu ry close the manifold gauge valves turn off the vacu um pump and disconnect the manifold gauge center port hose from vacuum pump Attach the manifold center port hose to a nitrogen cylinder with pressure regulator set to 150 psig 1034 kPa and purge the hose Open the manifold gauge valves to break the vacuum in the line set and indoor unit Close the man ifold gauge valves Shut off the nitrogen cylinder and remove the manifold gauge hose from the cylinder Open the manifold gauge valves to release the nitrogen from the line set and indoor unit Reconnect the manifold gauge to the vacuum pump turn
18. 120 K68 energizes outdoor fan B5 fan 2 in re sponse to thermostat demand 8 Terminal Strip TB14 all units TB14 terminal strip distributes 24V power from the thermo stat to control box components 9 Low Ambient Bypass Relay K58 all units K58 is a normally closed DPDT relay with a 24V coil used in both HP29 090 and HP29 120 units K58 is wired paral lel with the reversing valve L1 When L1 is energized in the cooling cycle K58 is also energized opening K58 1 On the HP29 120 K58 1 and K58 2 will open This shuts off power to the outdoor fans but does not by pass S11 and 541 which allow fans to cycle during cooling demand Dur ing heating demand K58 remains closed by passing S11 and S41 so fans can operate 10 GFI J11 Optional 2 units HP29 units may be equipped with a 110v ground fault in terrupter GFI The GFI is located the control box panel on the HP29 Separate wiring must be run for the 110v re ceptacle Page 7 B COOLING COMPONENTS IMPORTANT ALL major components indoor blower coil must be matched to Lennox recommendations for com pressor to be covered under warranty Refer to En gineering Handbook for approved system match ups 1 Scroll Compressor 1 All HP29 units utilize a scroll compressor The SCROLL COMPRESSOR DISCHARGE scroll compressor design is simple efficient and re quires few moving parts A cutaway diagram of the scroll compressor is shown in
19. 19 mm 2 6 oz 74g If line length is greater than 25 feet 7 62 m add this amount If line length is less than 25 feet 7 62 m subtract this amount NOTE Refrigerant line sets should not be longer than 100 feet 30 5 m Refrigerant line losses deduct from the net capac ity of the system Additional refrigerant required for such systems may also upset the refrigerant to oil ratio B Evacuating the System Evacuating the system of non condensables is critical for proper operation of the unit Non condensables are defined as any gas that will not condense under temperatures and pressures present during operation of an air conditioning system Non condensable such as water vapor nitrogen helium and air combines with refrigerant to produce sub stances that corrode copper piping and compressor parts 1 Connect manifold gauge set to the service valve ports as follows low pressure gauge to vapor line service valve high pressure gauge to liquid line service valve CAUTION Danger of Equipment Damage Avoid deep vacuum operation Do not use com pressors to evacuate a system Extremely low vacuums can cause internal arcing and compressor failure Damage caused by deep vacuum operation will void warranty A IMPORTANT A temperature vacuum gauge mercury vacuum U tube or thermocouple gauge should be used The usual Bourdon tube gauges are not accurate enough in the vacuum range 2 Connect the vacuum pump with
20. 29 units are field charged with the amount of R 22 re frigerant indicated in the charging procedure This charge is based on a matching indoor coil and outdoor coil with a 25 foot 7 6 m line set For varying lengths of line set refer to table 4 for refrigerant charge adjustment for HP29 series units Units are designed for line sets up to 50 ft 15 24 m Consult Lennox Refrigerant Piping Manual for line sets over 50 ft 15 24 m A WARNING Never use oxygen to pressurize refrigeration or air conditioning system Oxygen will explode on contact with oil and could cause personal injury Use nitrogen only for this purpose and be sure to use a regulator that can control the pressure down to 1 or 2 psig 6 9 to 13 8 kPa A CAUTION Any nitogen cylinder connected to system must have a 150 psig maximum setting regulator Never introduce pressures greater than 150 psig to any refrigerant system A Leak Testing Using an Electronic Leak Detector or Halide 1 Connect a cylinder of nitrogen with a pressure regulat ing valve to the center port of the manifold gauge set 2 Connect the high pressure hose of the manifold gauge set to the service port of the suction valve Normally the high pressure hose is connected to the liquid line port however connecting it to the suction port better protects the manifold gauge set from high pressure damage With both manifold valves closed open the valve on the R 22 bottle vapor
21. 90 2 29 120 2 29 120 2 Discharge amp _ mre m 7 e x ras m 3 _ HP29 090 tested with CB17 CBH17 95V 29 120 tested with CB17 CBH17 135V TABLE 7 NORMAL OPERATING PRESSURES Outdoor Coil Entering Air Temperature HP29 090 3 Discharge 10 psig 29 090 3 29 120 3 Discharge 10 psig 29 120 3 evraec fs 6 s 64 22 6 gt 6 es RD 95 35 2 36 _ sf 115 F 46 C HP29 090 tested with CB17 CBH17 95V HP29 120 tested with CB17 CBH17 135V V MAINTENANCE At the beginning of each cooling season the system should be checked as follows AWARNING Electric shock hazard Can cause inju ry or death Before attempting to per form any service or maintenance turn the electrical power to unit OFF at dis connect switch es Unit may have multiple power supplies Outdoor Unit 1 Clean and inspect the condenser coil You can flush the coil with a water hose 2 The outdoor fan motor is prelubricated and sealed No further lubrication is necessary 3 Visually inspect connecting lines and coils for evi dence of oil leaks 4 Check wiring for loose connections 5 Check for correct voltage at the unit while the unit is erating and while it is off 6 Check amp draw of the outdoor fan m
22. ARGING Page 16 Specifications Electrical Page 2 Leak Testing Page 16 Parts Arrangement Page 4 Evacuating Page 17 I UNIT COMPONENTS Page 6 Charging Page 18 Control Box 6 V MAINTENANCE Page 19 Cooling i Page 7 VI WIRING amp OPERATION SEQUENCE Defrost System Page 9 HP29 090 4 ed See engem Page 20 REFRIGERANT Page 14 HP29 120 e 24 START UP Page 15 Thermostat Connections Page 28 Technical Page 1 2001 Lennox Industries Inc Publications Litho U S A SPECIFICATIONS Wott HP HHI Vapor line o d in mm connection sweat 1 3 8 34 9 Neta 21 80 2 03 2 29 34 2 73 Outdoor sq ft m2 20 94 1 95 Coil Tube diameter in mm amp no of rows Fins per inch m Diameter in mm amp no of blades 1 24 610 4 2 24 610 3 Outdoor Motor hp W 1 1 2 373 2 1 3 249 Coil L s total air volume 5300 2500 8200 3870 Fan s Rpm 1075 1100 Motor Input Watts 350 700 Refrigerant charge Shipping weight Ibs kg 1 package 506 230 604 284 OPTIONAL ACCESSORIES Must Be Ordered Extra Hail Guards 83K37 79 91 SPECIFICATIONS General Model No HP29 090 3 HP29 120 3 Data Nominal Size
23. D ACROSS RELAY TRANSFER n 0 n H THERMOSTAT DISCHARG DISCONNECT ALL x POWER BEFORE SERVICING P49 TPLUG BLOWER MOTOR 6 WITCH DEFI TERMINATION SENSOR AMBIENT RANSF JFFMEN CONTROL _ ASS 2 HEAT PUMP OUTDOOR UNITS RMINA HP29 090 6 J M Y IF ANY WIRE IN THIS APPLIANCE IS REPLACED TET VIRG 534 950W ELECTRIC SHOCK HAZARD CAN CAUSE INJURY New Form No OR DEATH UNIT MUST BE GROUNDED IN ACCORDANCE WITH NATIONAL AND LOCAL CODES 535 029W 2005 Lennox Industries Inc Litho U S A Page 22 6 7 SEQUENCE OF OPERATION HP29 090 all production dates After each thermostat demand time delay locks out the circuit to compressor contactor coil and defrost control for 5 2 minutes At the end of the time period the time delay allows the compressor contactor and defrost control to be energized upon demand COOLING Cooling demand energizes through terminal Y1 at the indoor thermostat provided 5 minute time delay is sat isfied Voltage passes through N C K8 1 to CMCI defrost control K6 set coil is enegized N O K6 1 latching relay contacts close energizing L1 reversing valve K58 low ambient relay is energized N C K58 1 con tacts open eliminating S11 by pass Voltage passes through S11 low pressure switch switch will close provided liquid line pressure rises to 275 10 psig energizing outdoor fan relay K10 N O K10 1 cont
24. D LOCAL CODES 2005 Lennox Industries Inc Litho U S A Page 26 1 1 2 SEQUENCE OF OPERATION HP29 120 all production dates After each thermostat demand time delay locks out the circuit to compressor contactor coil and defrost control for 5 2 minutes At the end of the time period the time delay allows the compressor contactor and defrost control to be energized upon demand COOLING Cooling demand energizes through terminal Y1 at the indoor thermostat Voltage passes through N C K8 1 to CMCI defrost control K6 set coil is energized N O K6 1 latching relay contacts close energizing L1 reversing valve K58 low ambient relay is energized N C K58 1 con tacts open eleminating the 511 and S41 by pass Voltage passes through S11 low pressure switch switch will close provided liquid line pressure rises to 275 10 psig energizing K10 outdoor fan relay 1 N O K10 1 contacts close energizing outdoor fan B4 N C K10 2 contacts open de energizing HR1 crank case heater Voltage passes through S41 low ambient switch ener gizing K68 outdoor fan relay 2 N O K68 1 contacts close energizing outdoor fan B5 Compressor contactor K1 is energized N O K1 1 contacts close energizing compressor B1 G from indoor thermostat sends 24V through K8 2 N C contacts to G1 energizing indoor blower HEATING Heating demand energizes through terminal W1 at the indoor thermostat transfe
25. D WITH WIRE OF LIKE SIZE RATING AND INSULATION THICKNESS Nee Fera We WARNING ELECTRIC SHOCK HAZARD CAN CAUSE INJURY OR DEATH UNIT MUST BR GROUNDED IN ACCORDANCE 534 001W WITH NATIONAL AND LOCAL CODES D2002 Lennox Industries Inc Litho U S A Page 25 F HP29 120 Y G J M Production February 2006 and later 24V POWER 24V POWER ECONOMIZER HEAT I WI HEAT 2 W2 COOL 1 Y q DEFROST CONTROL DENOTES OPTIONAL COMPONENT CONNECTIONS KEY COMPONENT o 8 OMPRESSOR B4 MOTOR QUTDOOR FAN T Bo MOTOR QUTDOOR FAN 2 Cl ICAPACT TOR CMC T IMER DEFROST RES OR IHRI HEATER COMPRESSOR J36 JACK TEST COOL ACK BLOWER MOTOR 4 2 RELAY DEFR K6 T 2 RELAY K68 RELAY OUTDOOR 2 ILI IVALVE REVERSING H LOW PRESS LOW AMD K 1055 OF CHARGE 546 OST TER S124 J SWITCH DEFROST AUX M VOLTAGE UNITS ONLY IBI4 TERMINAL SIRIP CLASS II VOLTAGE MINIMUM CIRCUIT AMPACITY AND MAXIMUM OVERCURRENT PROTECTION HEAT PUMP OUTDOOR UNITS HP29 120 6 J M Y DISCONNECT ALL POWER BEFORE SERVICING HEAT PUMP SECTION B4 FOR USE WITH COPPER CONDUCTORS ONLY IF ANY WIRE IN THIS APPLIANCE IS REPLACED IT MUST BE REPLACED WITH WIRE OF LIKE SIZE RATING AND INSULATION THICKNESS WARNING ELECTRIC SHOCK HAZARD CAN CAUSE INJURY OR T GROUNDED IN ACCORDANCE WITH NATIONAL AN
26. HP29 090 control box components are shown in fig ure 3 The HP29 120P control box components are shown in figure 4 1 Disconnect Switch S48 Option 2 Units HP29 heat pumps units may be equipped with an optional disconnect switch S48 S48 is a factory installed toggle switch used to disconnect power to the unit 2 Outdoor Fan Capacitors C1 all units and C2 120P All HP29 units use single phase condenser fan motors Motors are equipped with a fan run capacitor to maximize motor efficiency Outdoor fan capacitors C1 and C2 assist in the start up of condenser fan motors B4 and B5 Capaci tor ratings are on outdoor fan motor nameplates 3 Compressor Contactor K1 all units All compressor contactors are three pole double break contactors with a 24V coil K1 energizes compressor B1 in both HP29 090 and HP29 120 units The contactor is en ergized from indoor thermostat terminal Y when thermo stat demand is present 4 Low Ambient Thermostat S41 HP29 120 only S41 is a N C limit which opens on temperature fall at 55 5 F The switch resets when temperature rises to 65 6 F 541 opens de energizes K68 which de energizes out door fan B5 When S41 closes fans will be re energi zed This intermittent fan operation increases indoor evap orator coil temperature to prevent icing 5 Latch Relay K6 all units HP29 units are plumbed so that the unit is in cooling mode when the reversing valve is energized Latch relay K6 con
27. IF ANY WIRE IN THIS APPLIANCE IS EA DD REPLACED IT MUST BE REPLACED WITH SWI TCH DISCONNEC T 120 1 60 WIRE OF LIKE SIZE RATING AND AUX INSULATION THICKNESS A RMINA R A AX u VOLTAGE UNITS ONLY LENNIXe HEAT PUMP OUTDOOR UNITS DISCONNECT ALL POWER BEFORE SERVICING HP29 120 2 6 J M Y FOR USE WITH COPPER CONDUCTORS ONLY HEAT PUMP SECTION B4 Supersedes New Form No 533 543W Litho U S A E HP29 120 3 Y G J M 24V POWER HEAT 1 1 HEAT 2 W2 COOL I YI DEFROST CONTROL 11 DENOTES OPTIONAL COMPONENT CONNECTIONS ic2__ s CAPACI TOR OUTDOOR FAN CMCI 55 _ HEATER COMPRESSOR_I 23 5 COOL 45 MOTOR 1 ACK BLOWER MOTOR OR OMPR K6 1 RELAY LATCH K68 RELAY OUTDOOR 2 ILL IPSO SI SWITCH LOW PR AMD S24 5WITCH LOSS OF CHARGE 541 THERMOSTAT LOW AMBIENT KIT 546 SWI TCH DEF RO RM INAT LON S124 SWITCH DEFROST AUX A M VOLTAGE UNITS ONLY 1814 ITERMINAL STRIP CLASS II VOLTAGE REFER TO UNIT RATING PLATE FOR MINIMUM CIRCUIT AMPACITY AND MAXIMUM OVERCURRENT PROTECTION DISCONNECT ALL POWER BEFORE SERVICING FOR USE WITH COPPER CONDUCTORS ONLY upereedes IF ANY WIRE IN THIS APPLIANCE IS REPLACED 07021 5 543W IT MUST BE REPLACE
28. Tons kW 7 5 26 4 10 35 2 Connections Liquid line o d in mm connection 5 8 15 9 5 8 15 9 sweat Vapor line o d in mm connection 1 3 8 34 9 1 3 8 34 9 Refrigerant dry air holding charge dry air holding charge Outdoor Net face area sq ft m2 Outer coil 30 0 2 79 2 29 34 2 73 Coil Inner coil 28 94 2 69 Tube diameter in mm amp no of rows 3 8 9 5 2 3 8 9 5 2 Fins per inch m 20 787 20 787 Outdoor Diameter in mm amp no of blades 1 24 610 4 2 24 610 3 Fais Motor hp W 1 3 4 560 2 1 3 249 cfm L s total air volume 5400 2550 8200 3870 Rpm 1075 1100 Motor Input Watts 600 700 Shipping Ibs kg 1 package 485 220 604 284 OPTIONAL ACCESSORIES Must Be Ordered Extra Hail Guards 29M45 79K91 Page 2 ELECTRICAL DATA Model No HP29 090 2 Line voltage data 60 hz 3 phase 208 230v 208 230v Rec max fuse 1 circuit breaker size amps co 80 TMinimum circuit ampacity 53 Rated load amps 28 8 14 7 10 8 37 8 Locked rotor amps 195 EMEN 239 T Outdoor Coil Fan Motor 1 phase Locked rotor amps total 3 2 9 4 7 9 4 TRefer to National or Canadian Electrical Code manual to determine wire fuse and disconnect size requirements NOTE Extremes of operating range are plus and minus 10 of line voltage 1HACR type under 100 amps U S only Compressor 1 ELECTRICAL DATA
29. acts close energizing outdoor fan B4 N C K10 2 contacts open de energizing HR1 crankcase heater Compressor contactor K1 is energized N O K1 1 contacts close energizing compressor B1 G from indoor thermostat sends 24V through K8 2 N C contacts to G1 energizing indoor blower Page 23 1 1 O N HEATING Heating demand energizes through terminal W1 at the indoor thermostat provided 5 minute time delay is sat isfied K8 transfer relay is energized N C K8 1 contacts open and N O contacts close sending voltage to defrost control K6 re set coil is energized N O K6 1 latching relay contacts open de energizing L1 reversing valve K58 low ambient relay is de energized N C K58 1 contacts close by passing S11 low ambient switch K10 outdoor fan relay is energized N O K10 1 con tacts close energizing outdoor fan B4 N C K10 2 contacts open de energizing HR1 crankcase heater Compressor contactor K1 is energized N O K1 1 contacts close energizing compressor B1 K8 2 N O contacts close sending 24V from G1 ener gizing indoor blower DEFROST MODE During heating operation when outdoor coil drops be low 35 4 F the defrost thermostat S6 closes When S6 closes K4 defrost relay is energized If defrost ther mostat remains closed at the end of 30 60 or 90 min utes defrost control energizes and defrost begins When defrost control energizes reversing valve L1
30. dd or remove charge in increments e Allow the system to stabilize each time refrigerant is added or removed 7 Use the following approach method along with the nor mal operating pressures to confirm readings APPROACH METHOD TXV SYSTEMS Ambient Temperature of 60 F 16 C or above 1 Use the same thermometer to take both the liquid line temperature and the outdoor ambient tempera ture Compare liquid line temperature to the outdoor ambient temperature Approach temperature equals the liquid line temperature minus the outdoor ambient temperature 2 Theapproach temperature should match values giv en in table 5 An approach temperature greater than the value shown indicates an undercharge An ap proach temperature less than the value shown indi cates an overcharge 3 Donotuse the approach method if system pres sures do not match the pressures given in table 6 The approach method is not valid for grossly over or undercharged systems TABLE 5 MODEL NO LIQUID TEMP MINUS AMBIENT F HP29 090 2 9 2 F 1 5 0 C 0 5 HP29 090 3 14 5 F 1 8 0 C 0 5 10 0 1 5 6 C 0 5 Note For best results the same thermometer should be used to check both outdoor ambient and liquid temperatures D Oil Charge Refer to compressor nameplate Page 18 TABLE 6 Normal Operating Pressures Outdoor Coil Entering Air Temperature 29 090 2 Discharge 10 psig 29 0
31. en finger tight then tighten an additional 1 6 turn To Open Vapor Line Service Valve 1 Remove stem cap with an adjustable wrench 2 Backthe stem out counterclockwise for a 1 4 turn 3 Replace stem cap and finger tighten then tighten an additional 1 6 turn To Close Vapor Line Service Valve 1 Remove stem cap with an adjustable wrench 2 Turn stem in clockwise for 1 4 turn 3 Replace stem cap Tighten finger tight then tighten an additional 1 6 turn Page 15 VAPOR LINE SERVICE VALVE USE ADJUSTABLE WRENCH ROTATE STEM CLOCKWISE 90 TO CLOSE ROTATE STEM COUNTER CLOCKWISE 90 TO OPEN STEM CAP TO INDOOR COIL LL SHOWN OPEN TO OUTDOOR COIL SERVICE 2 PORT _ 9 f we Ye ssh POR VALVE FIGURE 15 IH STARTUP The following is a general procedure and does not apply to all thermostat control systems Refer to sequence of op eration in this manual for more information WARNING Crankcase heaters must be energized for 24 hours before attempting to start compressors Set ther mostat so there is no compressor demand before closing disconnect switch Attempting to start compressors during the 24 hour warm up period could result in damage or failed compressors 1 Rotate the fan to check for frozen bearings or binding 2 Inspect all factory and field installed wiring for loose connections 3 Refer to section IV to accurately charge and check the charge on this unit 4
32. ens to terminate defrost the defrost timer loses power and resets Defrost timing is stopped until the next call for defrost when defrost thermostat closes HEAT PUMP G THERMOSTAT CONNECTIONS EAT PUMP UNIT FIELD W T IRING DIAGRAM WITH AUXILIARY E ECTRIC HE 5 2 THERMOSTAT sN L 17 17 WIT ECTRIC H F AND EAT VAC M2 P UNIT FIE PU 11 D WIRING DIAGRAM WITH N NOT REQ D WITH SOME TSTATS AUXILIARY UT HEAT TRANSFO FIELD PR RMER OVIDED J THERMOSTAT gt TO POWER gt SUPPLY PTN LOW VOLTAGE MAKE UP 9r BLUE Fa CONTROL RELAY m YELLOW BLOWER AN NOT REQ D VI MOTOR CONTACTOR RED TH SOME TSTATS RED HIGH VOLTAGE RED x I MAKE UP BD CBHI Page 28
33. ervice valves located in the liquid and vapor lines The service valves are manually operated See figures 14 and 15 The service ports are used for leak testing evacuating charging and checking charge 1 Liquid Line Service Valve A full service liquid line valve made by one of several manufacturers may be used All liquid line service valves function the same way differences are in construction Valves are not rebuildable If a valve has failed it must be replaced The liquid line service valve is illustrated in figure 14 A schrader valve is factory installed A service port cap is supplied to protect the schrader valve from contamination and to serve as primary leak seal LIQUID LINE SERVICE VALVE VALVE OPEN INSERT HEX WRENCH HERE ag INLET TO S INDOOR COIL OUTLET COMPRESSOR gt SERVICE PORT CAP SERVICE PORT LIQUID LINE SERVICE VALVE VALVE CLOSED RETAINING RING 2 units only STEM CAP A INSERT HEX WRENCH HERE INLET TO INDOOR COIL SERVICE PORT CAP VALVE CORE OPEN TO LINE SET WHEN VALVE IS CLOSED FRONT SEATED OUTLET TO COMPRESSOR FIGURE 14 To Access Service Port 1 Remove service port cap with an adjustable wrench 2 Connect gauge to the service port 3 When testing is completed replace service port cap Tighten finger tight then an additional 1 6 turn Do not over torque Open Liquid Line Service Valve 1 Remove stem cap with an
34. is de energized The switch automati cally resets when pressure in the liquid line rises to 55 5 psig 379 34 kPa 7 Reversing Valve L1 all units A reversing valve with an electromechanical solenoid is used to reverse refrigerant flow during unit operation L 1 is energized during cooling demand and defrost See figures 13 and NO TAG 8 Expansion Valves The HP29 120 2 uses two expansion valves in the liquid line adjacent to the left and right refrigerant coil The HP29 090 2 units have one expansion valve Aliquid line filter drier and check valve are connected in parallel with each expansion valve The check valve allows for reverse refrigerant flow The HP29 120 3 uses two internally checked expansion valveand the HP29 090 3 uses one in ternally checked expansion valve The valves are located in the liquid line adjacent to the left and right refrigerant coil In all units expansion valve control is provided by a super heat sensing bulb which is connected by a capillary tube to the expansion valve The sensing bulb is strapped to the vapor line where it exits the coil If the bulb senses low su perheat the expansion valve throttles down and restricts refrigerant flow through the coil When excessive super heat is sensed the valve opens to allow more refrigerant flow through the coil See figures 13 and NO TAG 9 Condenser Fan B4 both units B5 HP29 120 See page 2 for the specifications on the condenser fans used in
35. is ignored when the defrost test pins are jumpered Time Delay The timed off delay is five minutes long The delay helps to protect the compressor from short cycling in case the pow er to the unit is interrupted or the pressure switch opens The delay is bypassed by placing the timer select jumper across the TEST pins for 0 5 seconds Pressure Switch Circuit The defrost control incorporates a pressure switch circuit The high pressure switch S4 is factory connected to the board s HI PS terminals see figure 12 The switch is shown in the unit wiring diagram LO PS terminals are con nected in series with a jumper During a single demand cycle the defrost control will lock out the unit after the fifth time that the circuit is interrupted by any pressure switch wired to the control board In addition the diagnostic LEDs will indicate a locked out pressure switch after the fifth oc currence of an open pressure switch see Table 2 The unit will remain locked out until power to the board is inter rupted then re established or until the jumper is applied to the TEST pins for 0 5 seconds Diagnostic LEDs The defrost board uses two LEDs for diagnostics The LEDs flash a specific sequence according to the condition TABLE 2 Defrost Control Board Diagnostic LED Mode Green LED DS2 Red LED DS1 No power to con trol OFF OFF Normal operation Simultaneous Slow FLASH power to control Anti short cycle lock
36. ng the unit in the heating mode When heat demand is satisfied and power to the RESET coil is removed the normally open contacts remain open the normally closed contacts re main closed and the unit remains in the heating mode Page 6 6 Transfer Relay K8 all units Transfer relay K8 ensures that the indoor blower will oper ate during all modes of operation K8 also completes the circuit to Y1 on the defrost control board CMC1 The com bined operation of latch relay K6 and transfer relay K8 al lows the HP29 unit to use a conventional heat cool thermo stat instead of a heat pump thermostat When there is a de mand for cooling K8 1 closes completing the Y1 circuit to defrost control board CMC1 terminal Y1 Normally open K6 1 closes energizing the reversing valve K8 2 normaly closed contacts ensure an unbroken circuit between in door thermostat G and indoor blower contactor through terminals G and G1 on terminal strip TB14 When there is a heat demand normally closed K8 1 opens breaking the Y1 circuit to the defrost control CMC1 Power is sent to the RESET coil K6 1 opens de energizing the re versing valve K8 2 closes sending voltage from G1 to the indoor blower control 7 Outdoor Fan Relay K10 all units K68 HP29 120 Outdoor fan relay K10 is a DPDT relay and K68 is a SPDT relay with a 24V coil In all units K10 energizes outdoor fan B4 fan 1 in response to thermostat demand In the HP29
37. only 4 Open the high pressure side of the manifold to allow R 22 into the line set and indoor unit Weigh in a trace amount of R 22 A trace amount is enough refrigerant to equal 3 pounds 31 kPa pressure Close the valve on the R 22 bottle and the valve on the high pressure side of the manifold gauge set Disconnect R 22 bottle 5 Adjust nitrogen pressure to 300 psig 2068 kPa Open the valve on the high side of the manifold gauge set which will pressurize the system 6 After a short period of time open a refrigerant port to make sure the refrigerant added is adequate to be de tected Amounts of refrigerant will vary with line lengths Check all joints for leaks Purge nitrogen and R 22 mixture Correct any leaks and recheck 7 If brazing is necessary for repair bleed enough nitrogen through the system to ensure all oxygen is displaced Brazing with oxygen in the system will create copper ox ides which may cause restrictions the failure of compo nents and will affect the dielectric of refrigerant oil causing premature compressor failure Page 16 TABLE 4 UNIT MODEL MATCHED R 22 FOR 25 FEET LIQUID LINE ADJUSTMENT PER NUMBER INDOOR UNIT 7 6 m OF LINE DIAMETER FOOT 3 m OF LINE 5 8 in 16 mm 1 8 oz 51g 3 4 in 19 mm 2 6 oz 749 HP29 090 2 23 Ibs 10 4 kg HP29 090 3 CBI HERMIT 21 5 lbs 9 8 kg HP29 120 2 e 31 Ibs 14 1 kg 1 8 oz 519 HP29 120 3 30 Ibs 13 6 kg 3 4 in
38. otor Unit nameplate Actual Page 19 Check amp draw of the compressor Unit nameplate Actual NOTE If the owner complains of insufficient cooling gauge the unit and check the refrigerant charge Re fer to section on refrigerant charging in this instruc tion Indoor Coil 1 If necessary clean the 2 Check connecting lines and coils for evidence of oil leaks 3 If necessary check the condensate line and clean it Indoor Unit 1 Clean or change filters 2 Adjust the blower speed for cooling Measure the pres sure drop over the coil to determine the correct blower CFM Refer to the unit information service manual for pressure drop tables and procedure 3 On belt drive blowers check the belt for wear and proper tension 4 Check all wiring for loose connections 5 Check for correct voltage at the unit blower operat ing 6 Check amp draw on blower motor Unit nameplate Actual VI Wiring Diagram and Sequence of Operation A HP29 090 2 Y G J M 24V POWER 24V POWER ECONOMIZER BLOWER G HEAT WI HEAT 2 W2 O2 RANCO DEFROST COOL I YI CONTROL K58 3 P36 56 Y A COM FAN DESIGNATION VOLTAGE 3 y OUT 208 250 60 5 460 60 5 575 60 5 52 580 420 50 51
39. out Alternating Slow FLASH High pressure Slow FLASH OFF Switch fault High pressure ON OFF Switch lockout Page 12 COOLING MODE Refrigerant will flow in opposite direction heating mode LOW HIGH REVERSING E VALVE PRESSURE PRESSURE NOTE ARROWS INDICATE DIRECTION OF REFRIGERANT FLOW ACCUMULATOR OUTDOOR COIL TO REFRIGERAN gt DRUM EXPANSION VALVE INDOOR COIL VAPOR LINE SERVICE BI FLOW LIQUID VALVE lt OUTDOOR UNIT INDOOR UNIT FIGURE 13 Page 13 I REFRIGERANT SYSTEM A Plumbing Field refrigerant piping consists of liquid and vapor lines from the outdoor unit sweat connections to the indoor evaporator coil sweat connections Refer to table 3 for field fabricated refrigerant line sizes Refer to Lennox Re frigerant Piping manual Corp 9351 L9 for proper size type and application of field fabricated lines Separate dis charge and suction service ports are provided at the com pressor for connection of gauge manifold during charging procedure B Accumulator All HP29 2 units are equipped with an accumulator The accumulator prevents compressor slugging by holding ex cess refrigerant and then slowly metering it back into the system TABLE 3 REFRIGERANT LINE SIZES HP29 LIQUID VAPOR UNIT LINE LINE 1 3 8 in 85mm 1 3 8 in 35mm 5 8 in 16 mm 120 5 8 in 16 mm C Service Valves All HP29 units are equipped with s
40. ption in power to the unit before thermostat demand is satisfied or when a pressure switch resets If thermostat demand is satisfied and the off cycle is greater than 5 min utes the compressor will energize immediately on next heating or cooling demand 3 Pressure Switch Safety Circuits The defrost control incorporates a pressure switch safety circuit that allows the application of an additional pressure switch high pressure switch S4 is factory wired to this cir cuit PS1 and PS2 terminals are internally connected in se ries with a jumper internal to the control board During one demand cycle the defrost control will lock out the unit on the third instance that the unit goes off on any auto reset pressure switch wired to this circuit The diag nostic LEDs will display a pattern for a locked out pressure switch on the third open pressure switch occurrence See table 1 The unit will remain locked out until power is bro ken then remade to the control The PS2 safety circuit terminals are connected to the com pressor thermostat 4 Diagnostic LEDs The defrost board uses two LEDs for diagnostics The LEDs flash a specific sequence according to the condi tion See table 1 TABLE 1 voe 191 162 eee Flash togeiner with Flash together with wer to board LED 2 LED 1 Time Delay Alternating Flashes Alternating Flashes To Protect Compressor Amn TEDT Pressure Switch Open 00 Pressure Swi
41. r relay is energized N C K8 1 contacts open and N O contacts close sending voltage to CMCI defrost control K6 set coil is energized Page 27 3 N O K6 1 latching relay contacts open de energizing L1 reversing valve 4 K58 low ambient relay is de energized N C K58 1 6 10 contacts close by passing S11 low ambient switch and 541 low ambient thermostat K10 outdoor fan relay is energized N O K10 1 con tacts close energizing outdoor fan B4 N C K10 2 contacts open de energizing HR1 crankcase heater Voltage passes through S41 low ambient switch switch will close provided ambient is high enough energizing K68 outdoor fan relay 2 N O K68 1 con tacts close energizing outdoor fan B5 Compressor contactor K1 is energized N O K1 1 contacts close energizing compressor B1 K8 2 N O contacts close sending 24V from G1 ener gizing indoor blower DEFROST MODE During heating operation when outdoor coil drops be low 35 4 F defrost thermostats S6 circuit 1 and 124 circuit 2 close When 56 or 5124 close K4 de frost relay is energized If defrost thermostat remains closed at the end of 30 60 or 90 minutes defrost con trol energizes and defrost begins When defrost control energizes reversing valve L1 and indoor heat relay are energized Outdoor fan is de energized Defrost continues until 14 1 minutes have elapsed or until 546 defrost pressure switch opens When de frost pressure switch op
42. r run time ends the de frost relay is energized and defrost begins The defrost cycle is terminated by the defrost pressure switch or in 14 minutes whichever occurs first Defrost Control Components 1 Defrost Control Timing Pins Each timing pin selection provides a different accumu lated compressor run period during one thermostat run cycle This time period must occur before a defrost cycle is initiated The defrost interval can be adjusted to 30 60 or 90 minutes See figure 10 If no timing is selected the control defaults to the factory setting 90 minutes The de frost period is maximum of 14 minutes and cannot be adjusted A TEST option is provided for troubleshooting When the jumper is placed across the TEST pins the timing of all functions is reduced by a factor of 128 For example a 90 minute interval during TEST is 42 seconds and the 14 min ute defrost is reduced to 6 5 seconds The TEST mode may be started at anytime If the jumper is in the TEST position at power up or for longer than five min utes the control will ignore the TEST selection and will de fault to a 90 minute interval In order to test defrost cycle defrost thermostat must be closed or jumpered Once defrost is initiated remove jumper immediately Failure to remove jumper will reduce defrost time to seconds 2 Time Delay The timed off delay is five minutes long The delay feature is provided to help protect the compressor in case of inter ru
43. rip W128 compressor TB 14 wez contactor yes K1 Cee transfer relay K8 outdoor fan relay K10 I L co oo elle defrost timer FIGURE 3 HP29 120 3 CONTROL BOX relay switch K6 terminal strip TB 14 H Pu 88808008 e e cmc1 defrost timer outdoor fan relay K10 transfer relay K8 low ambient by pass realy i O capacitors K58 ground ut gan acm lug r 1 1 outdoor fan relay K68 compressor 1 defrost relay K4 low ambient thermostat S41 FIGURE 4 Page 5 I UNIT COMPONENTS The HP29 090 and HP29 120 components are shown in figures 1 and 2 A CONTROL BOX COMPONENTS The
44. rost cycle is initi ated The defrost interval can be adjusted to 30 60 or 90 minutes see figure 12 The defrost timing jumper is fac tory installed to provide a 60 minute defrost interval If the timing selector jumper is not in place the control de faults to a 90 minute defrost interval The maximum de frost period is 14 minutes and cannot be adjusted A TEST option is provided for troubleshooting The TEST mode may be started any time the unit is in the heating mode and the defrost thermostat is closed or jump ered If the jumper is in the TEST position at power up the control will ignore the test pins When the jumper is placed across the TEST pins for two seconds the control will enter the defrost mode If the jumper is removed before an addi tional 5 second period has elapsed 7 seconds total the unit will remain in defrost mode until the defrost thermostat opens or 14 minutes have passed If the jumper is not re moved until after the additional 5 second period has elapsed the defrost will terminate and the test option will not function again until the jumper is removed and re ap plied Compressor Delay The defrost board has a field selectable function to reduce occasional sounds that may occur while the unit is cycling in and out of the defrost mode The compressor will be cycled off for 30 seconds going in and out of the defrost mode when the compressor delay jumper is removed NOTE The 30 second compressor feature
45. tch Lockout On o Jj Malfunction oO 5 Anti Short Cycle This feature of the board prevents the compressor from be ing short cycled which could result in damage An internal board timer prevents the compressor from being ener gized for approximately 5 minutes after thermostat de mand is met During this time off the system refrigerant pressure is able to equalize between low and high sides which eases compressor start up 6 Ambient outdoor air Thermistor The defrost control board has two terminal connections for an ambient thermistor The thermistor compensates for changes in the outdoor air temperature This change in temperature can cause thermostat droop Droop may be defined as the difference between the room thermostat set point and the lowest temperature of the indoor air once the indoor blower is energized Cool air relative to thermo stat set point or desired room air temperature will enter the home when the indoor blower is energized The therm istor raises the thermostat set point by a fractional amount 1 or 2 F to keep the indoor air temperature near the ther mostat set point 7 Service Light Connection Terminal connections W1 L and C are for the addition of a thermostat service light This light can be used with any thermostat It is powered from the W1 second stage heat terminal of the indoor thermostat and is controlled by a dis charge line thermostat S54 The discharge line thermo
46. tenance checks Tables 6 and 7 are not a pro cedure for charging the system Minor variations in these pressures may be expected due to differ ences in installations Significant deviations could mean that the system is not properly charged or that a problem exists with some component in the sys tem Used prudently table 6 could serve as a useful service guides A IMPORTANT The following procedure requires accurate read ings of ambient outdoor temperature liquid tem perature and liquid pressure for proper charging Use a thermometer with accuracy of 2 F and a pressure gauge with accuracy of 5 PSIG 1 Attach gauge manifolds and operate unit in cooling mode until system stabilizes approximately 5 min utes 2 Check each circuit separately with all stages operat ing 3 Use a thermometer to accurately measure the outdoor ambient temperature 4 Apply the outdoor temperature to table 6 or 7 to deter mine normal operating pressures 5 Compare the normal operating pressures to the pres sures obtained from the gauges Minor variations in these pressures may be expected due to differences in installations Significant differences could mean that the system is not properly charged or that a problem exists with some component in the system Correct any system problems before proceeding 6 If liquid pressure is high remove refrigerant from the system If discharge pressure is low add refrigerant to the system e A
47. the scroll and the gas pocket becomes compressed figure 8 4 When compressed gas reaches the center it is discharged vertically into a chamber and discharge port in the top of the compressor figure 6 The discharge pressure forcing down on the top scroll helps seal the upper and lower edges tips of the scrolls figure 9 During a single orbit several pockets of gas are compressed simultaneously providing smooth continuous compression CROSS SECTION OF SCROLLS DISCHARGE STATIONARY SCROLL DISCHARG PRESSURE S SG 5 g SUCTION Z Y77777 SLPS AAA C SSS CUARTA ED CUN 222222292 SS KAN S d d Ni TIPS SEALED BY DISCHARGE PRESSURE ORBITING SCROLL FIGURE 9 2 Crankcase Heaters HR1 all units All HP29 units use a belly band crankcase heater Heater HR1 is wrapped around compressor B1 HR1 assures proper compressor lubrication at all times 3 High Pressure Switch S4 all units The high pressure switch is a manual reset SPST N C switch which opens on a pressure rise The switch is lo cated on the compressor discharge line and is wired to the defrost control board CMC1 When discharge pressure rises to 450 10 psig 3103 69 kPa the switch opens and the compressor is de energized through the CMC1 The Switch will close when discharge pressure drops to 300 20 psig 2068 138 kPA 4 Low Ambient Switch 511 all units

Lennox HP29 7.5-10 ton

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