Navien · Water Heater error code
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Guide · Water HeaterThermopile-powered gas controls report their state by counting blinks, then pausing. Reading the code correctly tells you whether the problem is the pilot, low thermopile power, overheating, a sensor or the control itself. Only codes confirmed by two sources are listed; everything gas-side is diagnosed here and referred to a licensed gas technician.
Guide · Water HeaterPower-vent tanks add a 120 V blower, an air pressure switch and often a vent temperature limit. Most no-heat calls are electrical supply, a kinked or water-filled pressure switch tube, condensate in the blower, or a restricted vent. The tech checks power and the low-voltage safety chain and inspects visually; gas valve, burner, igniter/flame sensor and vent repairs are referred to a licensed gas technician.
Guide · Water HeaterStanding-pilot gas tanks use a thermocouple or thermopile heated by the pilot to hold the gas valve open; FVIR models add a thermal switch and flame arrestor. This is a gas appliance: the tech's role here is to read the status light, confirm gas supply, note symptoms and hand off. Pilot assembly, thermocouple/thermopile, burner and gas valve work go to a licensed plumber or gas technician.
Navien · Water Heater
E003
Ignition failure
Navien · Water Heater
E004
False flame detected
Navien · Water Heater
E012
Flame loss during operation
Navien · Water Heater
E016
Overheating
Navien · Water Heater
E030
Exhaust overheat
Navien · Water Heater
E046
Limit control abnormality