Rheem Error Code 0: Standby – no call for operation (Heat Pump)

Updated October 15, 2026 · by Aurora Star Tech Inc.

Rheem error code 0 on a heat pump means: Standby - no call for operation. It is also called Rheem diagnostic code 0.

Low severityHeat PumpRheem/Ruud PRL-JEC heat pump (Comfort Control2 ICC)

Homeowner? What Rheem code 0 means for you

Usually minor Your heat pump is reporting: Standby - no call for operation. This code is usually informational or minor. The safe checks below often clear it; call us if it keeps showing up.

Safe things you can check yourself

Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
Check both breakers and the outdoor disconnect box beside the outdoor unit; all should be ON.
Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
In winter, keep snow and ice off and away from the outdoor unit. A short defrost cycle with steam is normal.
Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.

Call (647) 657-2977 Book a service call

Licensed technicians serving Vaughan, Toronto and the GTA.

What does Rheem error code 0 mean?

The dual seven-segment display on the ICC board shows 0 when line voltage and 24 VAC are present, the thermostat link is communicating and no compressor operation is requested. Normal standby.

Applies to: Rheem/Ruud PRL-JEC heat pumps with Comfort Control2 ICC

Safety: Gas, electrical and refrigerant work must be done by a licensed technician. Turn off power and gas before servicing, never bypass a safety control, and always follow the manufacturer's manual for your exact model.

Rheem models that use code 0

RPRL-024JEC RPRL-036JEC RPRL-048JEC RPRL-060JEC

Other Rheem Heat Pump codes

Code	Meaning
01	Long run time (compressor)
1 flash (L terminal)	L-terminal fault output: Long run cycle or low pressure
02	High side fault (compressor limit opened 4 times)
2 flashes (L terminal)	L-terminal fault output: High pressure control trip
03	Short cycling
3 flashes (L terminal)	L-terminal fault output: Unit short cycling
4 flashes (L terminal)	L-terminal fault output: Locked rotor
05	Open circuit - compressor will not run
5 flashes (L terminal)	L-terminal fault output: Compressor will not run, open circuit
06	Compressor open start circuit
6 flashes (L terminal)	L-terminal fault output: Open start circuit
07	Compressor open run circuit

All Rheem Heat Pump error codes →

Rheem code 0: homeowner questions

What does Rheem code 0 mean?

Standby - no call for operation. The dual seven-segment display on the ICC board shows 0 when line voltage and 24 VAC are present, the thermostat link is communicating and no compressor operation is requested. Normal standby.

Is it safe to keep using my heat pump with code 0?

Usually yes. Code 0 is normally minor, but if it keeps coming back have it checked.

Can I reset Rheem code 0 myself?

You can try one reset (power off for 30 seconds, then on). If Rheem code 0 comes back, the cause is still there and a licensed technician should check it.

Who can fix Rheem code 0 near me?

Aurora Star Tech Inc. repairs Rheem heat pumps in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.

Homeowner help: AC Running But Not Cooling: What to Check · Heat Pump Not Heating or Blowing Cold Air

Troubleshooting guides

Bypass the 3-minute timer and clear a lockout with TEST (PRL-JEC) Rheem · Heat Pump
Force a defrost test (PRL-JEC) Rheem · Heat Pump
Heat pump will not defrost / incomplete or excessive defrost Rheem · Heat Pump
Insufficient cooling / pressure problems Rheem · Heat Pump
Outdoor fan runs but compressor does not Rheem · Heat Pump
Outdoor unit will not run Rheem · Heat Pump
Review or clear stored faults on the ICC display (PRL-JEC) Rheem · Heat Pump

Source: Rheem PRL-JEC Installation Instructions, Comfort Control2 section 12.3 and 12.6 ICC diagnostic codes, pp.19 and 25. Written in our own words as a summary; always check the original manual.

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.