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 HeaterTankless units show the active code on the remote controller and/or a display on the unit. Many keep a short code history and a maintenance or performance data screen (flow, temperatures) reached through the control; how to reach it is on the tech sheet, often stored with the unit. Many errors clear by themselves when water flow stops, so the history matters. Gas, ignition, flame and venting codes are blocked: read them, then refer.
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.
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