Brand guide
All Noritz water heater guides
Choose the symptom or code that matches your unit. Confirm the exact model and control generation against the rating plate before following model-specific instructions.
Noritz Code 11: Ignition Failure
Noritz code 11 means ignition failure: the unit tried to light but never proved flame. Common causes, a safe reset, and when to call a pro.
Pilot and ignition problemsNoritz Code 12: Flame Failure
Noritz code 12 means flame failure: the burner lit, then lost flame. Common causes like gas supply and venting, and when repeats need a pro.
Error codes and flashing lightsNoritz Code 29: Neutralizer Lockout
Noritz code 29 means the condensate neutralizer cartridge needs service. What it means, how it's cleared, and when a repeat code needs a pro.
Leaks and floodingNoritz Leaking From the Bottom
Water under a Noritz can be condensate, a relief valve discharge, a filter or drain plug gasket, or the heat exchanger. How to identify it.
No hot waterNoritz Tankless Not Hot Enough
A Noritz running lukewarm may be undersized, scaled, limited by a mixing valve, crossed over, short on gas, or simply set too low.
Error codes and flashing lightsNoritz Tankless Water Heater Not Working
A Noritz tankless that won't heat usually has a power, flow, lockout, freeze, or gas problem. Read the code first, then follow the checks.
No hot waterNoritz Tankless With No Hot Water
A Noritz with no hot water usually has no 120 V, no flow signal, a lockout code, or a gas or ignition fault. Read the display first.
TanklessNoritz Tankless With No Water Flow
No water through a Noritz usually means closed isolation valves, a clogged inlet screen, scale, a failed mixing valve, or frozen pipes.