Rheem · Water heater
Code 51 Gas valve problem
What this code means
A fault in the gas valve or its wiring connections has been detected.
Most likely causes
- Faulty gas valve
- Loose or damaged wiring connector
What to try first
Not a DIY repair given the gas components involved.
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 Rheem error code Code 51 mean?
Gas valve problem. A fault in the gas valve or its wiring connections has been detected.
Can I fix Rheem code Code 51 myself?
Usually not. Not a DIY repair given the gas components involved. If the code returns after one reset, it needs a licensed technician.
What causes Rheem code Code 51?
The most common causes are: faulty gas valve; loose or damaged wiring connector.
Other Rheem water heater codes
All Rheem water heater error codes →
Other water heater brands: Ruud · Rinnai · 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.