Navien · Water heater
E046 Limit control / mixing valve abnormality
What this code means
An abnormality in the unit's limit control circuit or internal mixing valve has been detected.
Most likely causes
- Failing mixing valve actuator
- Scale buildup affecting valve operation
- Limit control sensor fault
What to try first
Not a DIY repair — needs the valve and limit control circuit tested by a technician.
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 Navien error code E046 mean?
Limit control / mixing valve abnormality. An abnormality in the unit's limit control circuit or internal mixing valve has been detected.
Can I fix Navien code E046 myself?
Usually not. Not a DIY repair — needs the valve and limit control circuit tested by a technician. If the code returns after one reset, it needs a licensed technician.
What causes Navien code E046?
The most common causes are: failing mixing valve actuator; scale buildup affecting valve operation; limit control sensor fault.
Other Navien water heater codes
All Navien water heater error codes →
Other water heater brands: Rheem · Ruud · Rinnai · 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.