Noritz · Water Heater error code
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Guide · Water HeaterA tankless heater only fires above a minimum flow rate and drops out when flow falls near that line. Clogged inlet screens, scaled heat exchangers, low-flow showerheads and aerators, and mixing valves that cut hot flow are the usual causes. The wrong turn is calling it a gas or ignition fault and replacing parts when the real issue is water flow.
Guide · Water HeaterOn electric tanks overheating usually means a thermostat welded closed or not clamped tightly against the tank, or a grounded element heating outside thermostat control. On gas tanks it is a gas control fault and must be referred. Treat it as a safety call: overheated water is a scald and tank-pressure hazard.
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.
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)
Noritz · Water Heater
29
Condensate drain problem