Navien · Water Heater error code
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Guide · Water HeaterIf cold is fine, the main supply is fine and the restriction is on the hot side: a fixture aerator or cartridge, debris from the tank lodged in a valve or line, a partly closed valve at the heater, or a restrictive heat trap nipple. First find out whether it is one fixture or the whole house; that tells you where to look.
Guide · Water HeaterA mini-tank (roughly 2.5 to 7 gallons) mounts under or near a sink on the cold supply and heats a small volume for that fixture. Some models plug into a standard outlet and others are hardwired; the circuit, T&P valve discharge and drain pan follow the installation instructions and local code. The tank must be full and purged of air before power goes on.
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