Rheem Error Code 66: Blower overspeed (BLOWER OVRSPEED) (Furnace)
Rheem error code 66 on a furnace means: Blower overspeed (BLOWER OVRSPEED). It is also called Rheem diagnostic code 66.
Homeowner? What Rheem code 66 means for you
Check, then call Your furnace is reporting: Blower overspeed (BLOWER OVRSPEED). This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
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.
- Make sure the unit has power: its on/off switch (often looks like a light switch near the unit) is ON and the breaker in the electrical panel is not tripped.
- Make sure the furnace front door or panel is closed properly; many furnaces will not run with the door switch open.
- Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
- Outside, make sure the intake and exhaust pipes or vent cap are not blocked by snow, ice, leaves or a nest.
- Check that the gas valve next to the furnace is open (handle in line with the pipe). Do not force it.
- 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) 657-2977Book a service call
Licensed technicians serving Vaughan, Toronto and the GTA.
What does Rheem error code 66 mean?
ECM blower running faster than expected - usually means very low static (missing panel/filter) or very high restriction.
Applies to: RGPE/RGLE 2-stage 80+
Common causes of Rheem code 66
- Blower door or filter/panels missing
- Duct disconnected
- Severe restriction
Rheem models that use code 66
RGLE-05(-)BMKRRGLE-07(-)AMKRRGLE-07(-)BRQRRGLE-10(-)BRMRRGLE-12(-)ARMRRGPE-05(-)BMKRRGPE-07(-)AMKRRGPE-07(-)BRQRRGPE-10(-)BRMRRGPE-12(-)ARMR
Other Rheem Furnace codes
All Rheem Furnace error codes →
Rheem code 66: homeowner questions
What does Rheem code 66 mean?
Blower overspeed (BLOWER OVRSPEED). ECM blower running faster than expected - usually means very low static (missing panel/filter) or very high restriction.
Is it safe to keep using my furnace with code 66?
It depends on the cause. This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
Can I reset Rheem code 66 myself?
You can try one reset (power off for 30 seconds, then on). If Rheem code 66 comes back, the cause is still there and a licensed technician should check it.
Who can fix Rheem code 66 near me?
Aurora Star Tech Inc. repairs Rheem furnaces in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.
Homeowner help: Furnace Not Turning On: What to Check · Furnace Blinking Light: What the Flash Codes Mean
Troubleshooting guides
- Blowing cold air All brands · Furnace
- No heat All brands · Furnace
- Short cycling All brands · Furnace
- Blower does not start after burners light Rheem · Furnace
- Burners go out before the heat call ends / short cycling Rheem · Furnace
- Communicating system not found / no communication Rheem · Furnace
- ECM blower does not start on heat Rheem · Furnace
- Furnace no heat - sequence troubleshooting Rheem · Furnace
- Furnace short cycles or does not hold setpoint Rheem · Furnace
- Gas valve does not shut off when heat call ends Rheem · Furnace
- Indoor blower does not start after burners light Rheem · Furnace
- Inducer (draft motor) does not start on heat call Rheem · Furnace
- Inducer does not run / does not run on low speed Rheem · Furnace
- Inducer runs 60 s then shuts off for 5 minutes, or runs continuously Rheem · Furnace
- Inducer runs 60 seconds then off for 5 minutes Rheem · Furnace
- No heat - inducer (IDM) does not start Rheem · Furnace
- No heat - POWER LED off Rheem · Furnace
- Read target airflow from the CFM LED Rheem · Furnace
- Thermostat does not hold room temperature Rheem · Furnace
Source: RGPE/RGLE: Table 16 p.49 / Table 20. 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.