System Diagnosis
Outdoor Ambient Temperature Fault. The sensor detects an abnormally low or high outdoor ambient temperature.
Troubleshooting guide for the Rheem Default system fault 84.
Sensor values that do not match the operating condition or drift when the harness is moved.
A control board issue can look like a failed sensor if the reference voltage or connector is unstable.
ACLogics has guided diagnostics for 35 Rheem fault codes and asks the right questions to narrow it down.