Water heater
Rinnai water heater error codes
Every Rinnai water heater code in our database, with plain-English meanings, likely causes, and what to try before calling for service. Codes can vary by model and year — always confirm against the legend on your unit or its manual.
- Code 10 Exhaust / venting obstruction safety
- Code 11 Ignition failure
- Code 12 Flame failure during operation
- Code 79 Freeze protection / condensate issue
- Code 65 Low water flow
- Code 01 Ignition or flame detection problem
- Code 06 Exhaust temperature sensor fault
- Code 07 Heat exchanger temperature sensor fault
- Code 16 Outlet water temperature sensor fault
- Code 25 Condensate drain blocked (float switch tripped)
- Code 61 Fan motor / airflow restriction
- Code 63 Low flow in recirculation loop
- LC (LC0–LC9) Scale buildup warning
- SS Scheduled service reminder