Navien · Water Heater error code
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Get lifetime accessOnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.
Guide · Water HeaterHybrids need enough room air and a clean air filter, a working condensate drain and the right mode. Many complaints are mode settings or a dirty filter. Refrigerant faults are sealed-system work.
Guide · Water HeaterScale insulates the heat exchanger, causing overheat codes and fluctuating temperature. Flush with a pump and descaling solution through the isolation valves.
Guide · Water HeaterCheck timer/settings, check valves, air in the loop and the pump itself. On tankless units with built-in pumps, a recirculation code may point to air or a leak in the loop.
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