Noritz · Water heater
Code 70 Circuit board abnormality
What this code means
A general fault has been detected on the main control board.
Most likely causes
- Board component failure
- Power surge damage
What to try first
Unplug the unit for 30 seconds to fully power-cycle before assuming board failure.
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 Noritz error code Code 70 mean?
Circuit board abnormality. A general fault has been detected on the main control board.
Can I fix Noritz code Code 70 myself?
Usually not. Unplug the unit for 30 seconds to fully power-cycle before assuming board failure. If the code returns after one reset, it needs a licensed technician.
What causes Noritz code Code 70?
The most common causes are: board component failure; power surge damage.
Other Noritz water heater codes
All Noritz water heater error codes →
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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.