A021 🟡 Repair Required
Rheem Error Code A021: Over-Temperature
⚠️ Your Rheem HVAC system has detected an overheating condition. Turn off the system and call a professional for repair.
How to Fix Rheem Code A021
- Turn off the system at the thermostat and at the circuit breaker
- Do not attempt to open the unit or perform any repairs yourself
- Contact a licensed HVAC technician for diagnosis and repair
What Does Rheem Error Code A021 Mean?
The A021 error code on your Rheem HVAC system indicates that the unit has reached an unsafe temperature. This is likely due to a malfunction in the system's temperature control or a problem with the cooling components. The system has automatically shut down to prevent damage or safety hazards. It's important to address this issue promptly to avoid further damage or potential safety risks.
Common Causes of Rheem Code A021
- Faulty temperature control board or sensor
- Clogged or dirty condenser coils
- Low refrigerant levels
- Failed compressor or fan motor
Applicable Rheem Models
Need a Pro to Fix Rheem Code A021?
A licensed HVAC technician can diagnose and fix this issue quickly.
Find a Licensed Tech Near You →Replacement Parts for Rheem Tankless Water Heater Code A021
Temperature Control Board OEM: RHEEM 4505229
Compressor OEM: RHEEM 4502775
Refrigerant