Rinnai · Water heater
Code 07 Heat exchanger temperature sensor fault
What this code means
The sensor monitoring heat exchanger temperature isn't reporting a valid reading — a distinct sensor from Code 06's exhaust sensor.
Most likely causes
- Failed thermistor
- Wiring connector fault at the sensor
What to try first
Not user-serviceable beyond a power-cycle; needs a technician with the wiring diagram.
Safety note: if this code returns after one clean reset, stop resetting it — repeated lockouts usually mean a real fault that needs a licensed technician. Never bypass a safety switch.
FAQ
What does Rinnai error code Code 07 mean?
Heat exchanger temperature sensor fault. The sensor monitoring heat exchanger temperature isn't reporting a valid reading — a distinct sensor from Code 06's exhaust sensor.
Can I fix Rinnai code Code 07 myself?
Usually not. Not user-serviceable beyond a power-cycle; needs a technician with the wiring diagram. If the code returns after one reset, it needs a licensed technician.
What causes Rinnai code Code 07?
The most common causes are: failed thermistor; wiring connector fault at the sensor.
Other Rinnai water heater codes
All Rinnai water heater error codes →
Other water heater brands: Rheem · Ruud · Navien · Noritz · Takagi · A.O. Smith · Bradford White · State / American · Generic electric · Generic tankless
This information may contain errors or not apply to your exact model — always double-check it against your appliance's own manual before acting. If there's any chance of a gas, fire, electrical, carbon monoxide, or other safety hazard, stop and call a licensed professional or the appropriate agency (e.g. your gas utility) instead of relying on this page alone.