Rheem Heat Pump Troubleshooting

The tables below contain the lists of possible breakdowns which may happen with Rheem heat pumps of different modifications. In case of Rheem heat pump not working you should address these checklists.

There are types of faults and problems with detailed descriptions, possible causes and solutions which may be recommended in the certain situations. If you feel the temperature in your house is getting higher, it may be because of heat pump fan not spinning, and therefore, heat pump not cooling. The information given below can be helpful for you then.

Rheem R-410A Heat Pump Troubleshooting

SYMPTOMPOSSIBLE CAUSEREMEDY
Unit will not run• Power off or loose electrical connection• Check for correct voltage at line voltage connections in condensing unit.
• Thermostat out of calibration - set too high• Reset.
• Defective control board• Check control board diagnostic codes.
• Blown fuses/tripped breaker• Replace fuses/reset breaker.
• Transformer defective• Check wiring. Replace transformer.
• High-pressure control open• Reset. Also see high head pressure remedy. The high- pressure control opens at 610 PSIG.
• Miswiring of communications (communication light on continuously)• Check communication wiring.
Outdoor fan runs, compressor doesn't• Run or start capacitor defective• Replace.
• Start relay defective• Replace.
• Loose connection• Check for correct voltage at compressor. Check and tighten all connections.
• Compressor stuck, grounded or open motor winding, open internal overload.• Wait at least 3 hours for overload to reset. If still open, replace the compressor.
• Low-voltage condition• Add start kit components.
Insufficient cooling• Improperly sized unit• Recalculate load.
• Improper indoor airflow• Check. Should be approximately 400 CFM per ton.
• Incorrect refrigerant charge• Charge per procedure attached to unit service panel.
• Air, noncondensibles, or moisture in system• Recover refrigerant. Evacuate and recharge. Add filter drier.
Compressor short cycles• Incorrect voltage• At compressor terminals, voltage must be ± 10% of nameplate marking when unit is operating.
• Defective overload protector• Replace. Check for correct voltage.
• Refrigerant undercharge• Add refrigerant.
Registers sweat• Low indoor airflow• Increase speed of blower or reduce restriction. Replace air filter.
High head, low vapor pressures• Restriction in liquid line, expansion device, or filter drier• Remove or replace defective component.
• Bad TXV• Replace TXV.
High head, high or normal vapor pressure - Cooling mode• Dirty outdoor coil• Clean coil.
• Refrigerant overcharge• Correct system charge.
• Outdoor fan not running• Repair or replace.
• Air or noncondensibles in system• Recover refrigerant. Evacuate and recharge.
Low head, high vapor pressures• Bad TXV• Replace TXV.
• Bad compressor• Replace compressor.
Low vapor, cool compressor, iced indoor coil• Low indoor airflow• Increase speed of blower or reduce restriction. Replace air filter.
• Operating below 65°F outdoors• Add Low Ambient Kit.
• Moisture in system• Recover refrigerant. Evacuate and recharge. Add filter drier.
High vapor pressure• Excessive load• Recheck load calculation.
• Defective compressor• Replace.
Fluctuating head and vapor pressures• TXV hunting• Check TXV bulb clamp. Check air distribution on coil. Replace TXV.
• Air or noncondensibles in system• Recover refrigerant. Evacuate and recharge.
Gurgle or pulsing noise at expansion device or liquid line• Air or noncondensibles in system• Recover refrigerant. Evacuate and recharge.

Rheem RP13 Heat Pump Troubleshooting

SYMPTOMPOSSIBLE CAUSECHECK OR REMEDIES
Voltage present on compressor contactor and compressor won't runCompressor start componentsCheck start capacitor.
Check potential relay.
Run capacitorCheck with ohmmeter
Internal overloadAllow time to reset.
Compressor windingsCheck for correct ohms.
Voltage present on line side of compressor contactor onlyThermostatCheck for control voltage to contactor coil.
Compressor control circuitHigh-pressure switch
Low-pressure switch
Ambient thermostat
Solid-state protection control or internal thermal sensors
Compressor timed off/on control or interlock
No voltage on line side of compressor contactorBlown fuses or tripped circuit breakerCheck for short in wiring or unit.
Improper wiringRecheck wiring diagram.
Improper voltageHigh voltageWrong unit
Power supply problem
Low voltageWrong unit
Power supply problem
Wiring undersized
Loose connections
Single Phasing (3 phase)Check incoming power and fusing.
Liquid in the compressor shellFaulty or missing crankcase heaterReplace crankcase heater.
Too much liquid in systemIncorrect pipingCheck piping guidelines.
OverchargeCheck and adjust charge.
MoisturePoor evacuation on installation or during serviceIn each case, the cure is the same. Recover refrigerant. Add filter drier, evacuate, and recharge.
High head pressureNoncondensibles air
Unusual head and suction readingsWrong refrigerant or mixed refrigerants
Foreign matter - copper filingsCopper tubing cuttings
Copper oxideDirty copper piping or nitrogen not used when brazing
Welding scaleNitrogen not used during brazing
Soldering fluxAdding flux before seating copper partway
Excess soft solderWrong solder material
Compressor failuresLine tubing too largeReduce pipe size to improve oil return.
Low suction pressureLow chargeCheck system charge.
Refrigerant leaksRepair and recharge.
Cold, noisy compressor - SluggingDilution of oil with refrigerantObserve piping guidelines.
Noisy compressorMigrationCheck crankcase heater.
Cold, sweating compressorFloodingCheck system charge.
Low loadReduced airflowDirty filter
Dirty coil
Wrong duct size
Restricted duct
Thermostat settingAdvise customer.
Short cycling of compressorFaulty high- or low-pressure controlReplace control.
Loose wiringCheck all control wires.
ThermostatIn supply air stream, out of calibration
Customer misuse
On start-upIncorrect pipingReview pipe size guidelines.
TEV hunting when runningFaulty TEVReplace TEV.

Rheem MPi Series Heat Pump Troubleshooting

FlashesFault ModesSolution
1 x redHeating unit on (possible circulator fault)compressor over temperature
2 x redHeating unit offcompressor fault condition
3 x redcompressor cooling fault condition
4 x redtank thermistor fault condition
5 x redevaporator thermistor fault condition
6 x redcompressor thermistor fault condition
9 x redcompressor fault condition

Rheem RRPL-B Series Heat Pump Troubleshooting

LED 1LED 2Control Board Status
OFFOFFNo Power
ONONCoil Sensor Failure
OFFONAmbient Sensor Failure
FLASHFLASHNormal
OFFFLASHLow Pressure Lockout (short test Dins to reset)
FLASHOFFHigh Pressure Lockout (short test Dins to reset)
ONFLASHLow Pressure Control Open
FLASHONHigh Pressure Control Open
Alternate Flashing5 Minute Time Delay

Rheem RP15 Heat Pump Troubleshooting

SYMPTOMSPOSSIBLE CAUSECHECK OR REMEDIES
Compressor failuresLine tubing too longAdd oil to the recommended level
Line tubing too largeReduce pipe size to improve oil return
Low suction pressureLow chargeCheck system charge
Refrigerant leaksRepair and recharge
Cold, Noisy compressor - SluggingDilution of Oil with RefrigerantObserve piping guidelines
Noisy compressorMigrationCheck crankcase heater
Cold, sweating compressorFloodingCheck system charge
Low LoadReduced air flowDirty filter
Dirty coil
Wrong duct size
Restricted duct
Thermostat settingAdvise customer
Short cyding of compressorFaulty pressure controlReplace control
Loose wiringCheck all control wires
ThermostatIn supply air stream, out of calibration,
Customer misuse
Liquid in the compressor shellFaulty or missing crankcase heaterReplace crankcase heater
Too much liquid in systemIncorrect pipingCheck Piping guidelines
OverchargeCheck and adjust charge
On start upIncorrect pipingReview pipe size guidelines
TEV hunting when runningOversized TEVCheck TEV application
Poor system control using a TEVLoose sensing bulbSecure the bulb and insulate
Bulb in wrong locationRelocate bulb
Wrong size TEVUse correct replacement
Improper superheat settingAdjust, if possible; Replace, if not
Poor system control using capillary tubesOverchargeCheck system charge
High head pressuresDirty heat pump
Restricted air flow
Recirculation of air
Evaporator air flow too lowAdjust air flow to 400 CFM [188.8 L/s]/Ton
High Superheat, Low Suction PressureMoisture freezing and blocking valveRecover charge, install filter-drier, evacuate system, recharge
Dirt or foreign material blocking valveRecover charge, install filter-drier, evacuate system, recharge
Low refrigerant chargeCorrect the charge
Vapor bubbles in liquid lineRemove restriction in liquid line Correct the refrigerant charge
Remove non-condensable gases
Size liquid line correctly
Misapplication of internally equalized valveUse correct TEV
Plugged external equalizer lineRemove external equalizer line restriction
Undersized TEVReplace with correct valve
Loss of charge from power head sensing bulbReplace power head or complete TEV
Charge migration from sensing bulb to power head (Warm power head with warm, wet cloth. Does valve operate correctly now?)Ensure TEV is warmer than sensing bulb
Improper superheat adjustment (Only applicable to TEV with adjustable superheat settings)Adjust superheat setting counter- clockwise
Valve feeds too much refrigerant, with low superheat and higher than mat suction pressureMoisture causing valve to stick open.Recover refrigerant, replace filter- drier, evacuate system and then nor- recharge
Dirt or foreign material causing valve to stick openRecover refrigerant, replace filter- drier, evacuate system and recharge
TEV seat leak (A gurgling or hissing sound is heard AT THE TEV during the off cycle, if this is the cause.) NOT APPLICABLE TO BLEED PORT VALVES.Replace the TEV
Oversized TEVInstall correct TEV
Incorrect sensing bulb locationInstall bulb with two mounting straps, in 2:00 or 4:00 position on suction line, with insulation
Low superheat adjustment (only applicable to TEV with adjustable superheat setting)Turn superheat adjustment clockwise
Incorrectly installed, or restricted external equalizer lineRemove restriction, or relocate external equalizer

Rheem PPL-JAZ Series Heat Pump Troubleshooting

FAULTDESCRIPTIONSOLUTION
Motor rocks slightly when startingNo movementThis is normal start-up for ECM.
Motor will not startNo movementCheck power at motor.
Check low voltage (24-vac R to C) at motor.
Check low voltage connections (G.Y W. R. C) at motor.
Check for unseated Dins in connectors on motor harness.
Check motor for tight shaft.
Perform motor/control replacement check.
Run moisture check.
Motor rocksCheck for loose or non-compliant motor mount.
Make sure blower wheel is tight on shaft.
Perform motor/control replacement check.
Motor oscillates up and down while being tested off of blowerIt is normal for motor to oscillate with no load on shaft.
Motor starts, but runs erraticallyVaries up and down or intermittentCheck line voltage for variation or “saq."
Check law voltage connections (G,Y W, R ; C) at motor, unseated pins in motor harness connectors.
Check “Bk” for erratic cfm command (in variable speed applications).
Check system controls, thermostat.
Perform moisture check.
“Hunts" or “puffs” at high cfm (SDeed)If removing panel or filter reduces “puffing,” reduce restriction or reduce maximum airflow.
Stays at low cfm despite system call for cool or heat cfmCheck lew voltage (thermostat) wires and connections.
Verity fan is not in delay mode. Wait until delay is complete.
Perform motor/control replacement check.
Stays at high cfmCheck to see if “R” is missing/not connected at motor
Verify fan is not in delay mode. Wait until delay is complete.
Perform motor/control replacement check.
Blower will not shut offCheck to see if there is current leakage from controls into G, Y, or W. Check for Triac switched thermostat or solid state relay.
Excessive noiseNoisy blower or cabinetdetermine if it’s air. cabinet, duct, or motor noise.
Check for loose blower housing. panels. etc.
If high static is creating high blower speed, check for air whistling through seams in ducts, cabinets, or panels.
If high static is creating high blower speed. check for cabinet/duct deformation.
“Hunts" or “puffs” at high cfm (speed)If removing panel or filter reduces '‘puffing; reduce restriction or reduce maximum airflow.
Evidence of moistureMotor failure or malfunction has occurred and moisture is presentReplace motor and perform moisture check..
Evidence of moisture present inside air moverPerform moisture check.

Rheem RRP Series Heat Pump Troubleshooting

Dual 7-Segment LEDs Display CodeStatus/Possible Cause - Troubleshooting Information
L 8-Check model data card is properly connected.
-Cycle power - remove power until all the lights on the inverter have gone out. Then restore power to inverter then ICC.
-Replace model data card
L15-Verify high voltage connections at the terminal block, filter and inverter are all tight.
- Verify communication cable connection between the inverter and ICC is complete. -Check the U/V/W output wires are correct.
- Verify there is not a short in the filter or choke.
- Verify input voltage is within 187VAC and 252VAC.
-Check outdoor airflow and verify OD fan is operating.
-Check the power inverter heat sync for debris.
-Check model data card for defects -Replace model data card -Check charge level. Reduce charge.
-If none of the above corrects the issue, replace drive.
L16-Power cycle the system. Verify all lights on the inverter are out prior to returning power to the drive.
-Check the U/V/W output wires are correct.
-Check charge level. Reduce charge.
- Check continuity of discharge line thermistor and connection at the drive. If issue persists, replace the thermistor.
-If none of the above corrects the issue, replace drive.
L17-Outdoor ambient is above 125 # F. Allow unit to cool and condensing pressure to reduce before restarting.
-Outdoor ambient is below 0 # F. Allow unit to heat up and evaporating pressure to increase before restarting.
- Check charge level. Reduce charge.
L18- Verify communication cable connection between the inverter and ICC is complete.
- Verify shielding on communication cable is adequately connected to the connector.
- Verify crimp terminals in the ICC to inverter communication cable are fully inserted and making good contact with the receptacle.
31-Check charge level. Reduce charge. -Charge migration could have occurred resulting in high compression ratio.
-If ambient above 110*F or below 0 # F compression ratio could be too high for low speed operation.
-ICC will clear this fault and restart independently.
L31-Check charge level. Reduce charge. -Outdoor ambient is above 125 # F. Allow unit to cool and condensing pressure to reduce before restarting.
- Outdoor ambient is below 0*F. Allow unit to heat up and evaporating pressure increase before restarting.
-Cycle power to restart.
L32- Check Thermistor continuity. The compressor thermistor is a 10k thermistor.
L33- Check Thermistor continuity. The Evaporator thermistor is a 10k thermistor.
L36-Check pressure transducer wiring harness for continuity while attached to sensor.
- Check 5Vdc is constant between black and red at the sensor.
-Check return voltage between Black and Green terminals on back of control board.
-Calculate the gauge pressure from the voltage readings: PSIG = (375 *
-On a legacy controlled system verify that the voltage readings convert to the

Rheem RJNA Series Heat Pump Troubleshooting

Discharge PressureSuction PressureSub-coolingCompressor AmpsSystem Problem
HighLow/ NormalHighHighOvercharge
LowLowLowLowUndercharge
LowLowHighLowLiquid Line Restriction
HighLowLowLowLow Evaporator Airflow
HighHigh/ NormalLowHighDirty outdoor Coil
LowLowHighLowLow Outside Ambient temperature
LowLowHighLowTXV sensing bulb charge lost
HighHighLowHighPoorly Insulated Sensing Bulb