Noritz · Water heater
Code 11 Ignition failure
What this code means
The unit couldn't establish air, spark, and gas together to light the burner.
Most likely causes
- Low propane level or interrupted natural gas supply
- Blocked air intake or exhaust vent
- Debris on the ignition plug/igniter
What to try first
Verify the gas type matches the unit (natural gas vs. propane) and that the gas valve is fully open.
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 11 mean?
Ignition failure. The unit couldn't establish air, spark, and gas together to light the burner.
Can I fix Noritz code Code 11 myself?
Usually not. Verify the gas type matches the unit (natural gas vs. propane) and that the gas valve is fully open. If the code returns after one reset, it needs a licensed technician.
What causes Noritz code Code 11?
The most common causes are: low propane level or interrupted natural gas supply; blocked air intake or exhaust vent; debris on the ignition plug/igniter.
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.