Noritz · Water Heater error code
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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.
Noritz · Water Heater
05
Service due warning
Noritz · Water Heater
10
Combustion / exhaust problem
Noritz · Water Heater
11
Ignition failure
Noritz · Water Heater
12
Flame loss / weak flame
Noritz · Water Heater
14
Thermal fuse tripped (heat exchanger overheat)
Noritz · Water Heater
16
Outlet temperature spike (often scale)