Rheem AC Error Codes – Causes and Solutions

If you’re experiencing issues with your Rheem AC, our guide on error codes is here to help. Our comprehensive resource covers everything from troubleshooting tips to fault code lists and PDF manuals to diagnose and solve problems with ease. Get your air conditioner back up and running in no time with our guide.

Codes Table

Display CodesPossible Cause
0- StandbyNo command for unit operation
c - First Stage CoolingUnit has received a command for first stage cooling
c FlashingAnti-short cycle timer (3 minutes) or Minimum run timer (30 seconds) active
C - Second Stage CoolingUnit has received a command for second stage cooling
C FlashingAnti-short cycle timer (3 minutes) or Minimum run timer (30 seconds) active
h - First Stage Heat PumpUnit has received a command for first stage heat pump
h FlashingAnti-short cycle timer (3 minutes) or Minimum run timer (30 seconds) action
H - Second Stage Heat PumUnit has received a command for second stage heat pump
H FlashingAnti-short cycle timer (3 minutes) or Minimum run timer (30 seconds) active
d - Defrost ActiveThe unit is undergoing a defrost cycle
t - Test ModTest Mod
P - Protector TripA command for compressor operation is present but no current is measured to the compressor
01 - Long Run Time (Compressor)The compressor has continuously run for more than 18 hours in the cooling mode.
02 - High PressureCompressor limit has opened four (4) times within a call for operation
03 - Short CyclingICC detects the run time for the past four (4) compressor or cycles is less than three (3) minutes each
L4 - Locked RotorThe ICC detects four (4) consecutive protector trips have occurred and the average run time for each trip is less than 15 seconds
05 - Open circuit (Compressor Will not Run)The ICC has had a protector trip for longer than 4 hours
06 - Compressor Open Start CircuitThe ICC detects current in the Run circuit but not in the Start circuit of the compressor
L6 - Compressor Open Start CircuitThe ICC detects current in the Run circuit but not in the Start circuit of the compressor four (4) times in one compressor call
07 - Compressor Open Run CircuitThe ICC detects current in the Start circuit but not in the Run circuit of the compressor
L7 - Compressor Open Run CircuitThe ICC detects current in the Start circuit but not in the Run circuit of the compressor four (4) times in one compressor call
09 - Low Secondary VoltsThe secondary voltage at R and C is below 18VAC
21 - Low Pressure Control OpenThe ICC detects the LPC is open. Note: The low pressure control is ignored for the first 90 seconds of compressor operation
L21 FlashingActive Protection, Low Pressure Control Trip
27Low Line Voltage or No Line Voltage Fault
28High Line Voltage Fault
29High Pressure Control Open. The ICC detects the HPC is open
L29 Flashing - Active ProtectionHigh Pressure Control Trip
30 - Fuse OpenThe ICC detects the on—board fuse is open
80 - Low Air FlowThe ICC detects that the indoor unit is not providing the minimum airflow requirements.
83 - Condenser Coil Temperature FaultThe sensor detects an abnormally low or high coil temperature
84 - Outdoor Ambient Temperature FaultThe sensor detects an abnormally low or high outdoor ambient temperature
93 - Internal Control FaultThe control is not functioning properly.
d1N0 Shared Data
d3 - Airflow CFM MismatchThe indoor air mover (air handler/furnace) cannot supply the required airflow for proper system operation
d4 - (Device) Memory Card Invalid for DeviceThe data in the memory card inserted into the control board does not match the data in the control.
d8 - Old Shared DataSystem data is obsolete

Diagnostic Codes

Descriptions of the ICC diagnostic codes are provided below: NOTE: Codes must be read from correct side to avoid an error in reading codes.

Rheem AC ICC Diagnostic Codes
Rheem AC ICC Diagnostic Codes

Electrical Checks Flowchart

Thermostat Call For Cooling, No Cooling

Rheem AC Electrical Checks Flowchart
Rheem AC Electrical Checks Flowchart

Troubleshooting

Rheem AC Troubleshooting
Rheem AC Troubleshooting

Disconnect all power to unit before servicing. Contactor may break only one side. Failure to shut off power can cause electrical shock resulting in personal injury or death.

SYMPTOM: Unit will not run

POSSIBLE CAUSE:

  1. Power off or loose electrical connection
  2. Thermostat out of calibration – set too high
  3. Defective control board
  4. Blown fuses/tripped breaker
  5. Transformer defective
  6. High-pressure control open/Low-pressure control open
  7. Miswiring of communications

REMEDY:

  1. Check for correct voltage at line voltage connections in condensing unit.
  2. Reset.
  3. Check control board diagnostic codes.
  4. Replace fuses/reset breaker.
  5. Check wiring. Replace transformer.
  6. Reset. Also see high head pressure remedy. The highpressure control opens at 610 PSIG.
  7. Check communication wiring

SYMPTOM: Outdoor fan runs, compressor doesn’t

POSSIBLE CAUSE:

  1. Run or start capacitor defective
  2. Contactor defective
  3. Loose connection
  4. Compressor stuck, grounded or open motor winding, open internal overload.
  5. Low-voltage condition

REMEDY:

  1. Replace.
  2. Replace.
  3. Check for correct voltage at compressor. Check and tighten all connections.
  4. Wait at least 3 hours for overload to reset. If still open, replace the compressor.
  5. Add start kit components.

SYMPTOM: Insufficient cooling

POSSIBLE CAUSE:

  1. Improperly sized unit
  2. Improper indoor airflow
  3. Incorrect refrigerant charge
  4. Air, noncondensibles, or moisture in system
  5. Bad ID TXV

REMEDY:

  1. Recalculate load.
  2. Check. Should be approximately 400 CFM per ton.
  3. Charge per procedure attached to unit service panel.
  4. Recover refrigerant. Evacuate and recharge. Add filter drier.
  5. Replace TXV

SYMPTOM: Compressor short cycles

POSSIBLE CAUSE:

  1. Incorrect voltage
  2. Defective overload protector
  3. Refrigerant undercharge

REMEDY:

  1. At compressor terminals, voltage must be ± 10% of nameplate marking when unit is operating.
  2. Replace. Check for correct voltage.
  3. Add refrigerant.

SYMPTOM:  High head, low vapor pressures

POSSIBLE CAUSE:

  1. Restriction in liquid line, expansion device, or filter drier
  2. Bad TXV

REMEDY:

  1. Remove or replace defective component.
  2. Replace TXV

SYMPTOM:  High head, high or normal vapor pressure – Cooling mode

POSSIBLE CAUSE:

  1. Dirty outdoor coil
  2. Refrigerant overcharge
  3. Outdoor fan not running
  4. Air or noncondensibles in system

REMEDY:

  1. Clean coil.
  2. Correct system charge.
  3. Repair or replace.
  4. Recover refrigerant. Evacuate and recharge

SYMPTOM:  Low head, high vapor pressures

POSSIBLE CAUSE:

  1. Bad TXV
  2. Bad compressor

REMEDY:

  1. Replace TXV.
  2. Replace compressor

SYMPTOM:  Low vapor, cool compressor, iced indoor coil

POSSIBLE CAUSE:

  1. Low indoor airflow
  2. Operating below 65°F outdoors
  3. Moisture in system
  4. Closed ID circuit

REMEDY:

  1. Increase speed of blower or reduce restriction. Replace air filter.
  2. Add Low Ambient Kit.
  3. Recover refrigerant. Evacuate and recharge. Add filter drier.
  4. Repair or replace ID coil

SYMPTOM: High vapor pressure

POSSIBLE CAUSE:

  1. Excessive load
  2. Defective compressor

REMEDY:

  1. Recheck load calculation.
  2. Replace.

SYMPTOM: Fluctuating head and vapor pressures

POSSIBLE CAUSE:

  1. TXV hunting
  2. Air or noncondensibles in system

REMEDY:

  1. Check TXV bulb clamp. Check air distribution on coil. Replace TXV.
  2. Recover refrigerant. Evacuate and recharge.

Service Analyzer Charts

Rheem AC Service Analyzer Charts
Rheem AC Service Analyzer Charts

Manual Pdf

Classic RA13 Condenser Manual

source: www.rheem.com

Danny Reese



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