Noritz Error Codes

Find troubleshooting guides for all Noritz error codes.

14 error codes across 1 appliance types

Waterheater

Code	Meaning	Severity
11	The unit attempted ignition three times and could not establish a flame. No flame signal was detected by the flame rod during any attempt. high	high
12	The flame rod detected that the burner flame was lost after successful ignition. The unit established a flame but it extinguished before the call for hot water ended. high	high
14	The thermal fuse, a one-time safety device in the heat exchanger circuit, has blown due to excessive heat. The unit will not operate until the fuse is physically replaced by a technician. critical	critical
16	The gas pressure sensor or combustion monitoring system detected that gas supply pressure is outside the acceptable operating range, or that combustion is abnormal due to pressure issues. high	high
20	The combustion fan (blower motor) has failed, stalled, or cannot reach the required operating speed. The unit cannot run without the fan providing combustion air and evacuating exhaust gases. high	high
29	The heat exchanger temperature sensor detected a temperature exceeding the safe operating threshold (160 to 180 degrees F). The unit shut down to prevent damage. high	high
90	The combustion sensor detected abnormal combustion. Most commonly caused by exhaust gases recirculating back into the air intake, producing oxygen-depleted combustion air. high	high
CONDENSATE-DRAIN	Condensing Noritz units (NRCP series) extract extra heat from flue gases, producing acidic condensate that must drain continuously. A blocked or frozen condensate drain causes unit shutdown and can trigger Code 29. moderate	moderate
HUB	Master reference for all Noritz tankless water heater error codes across the NR and NRCP condensing series. low	low
IGN-FAILURE	The Noritz water heater fails to ignite when hot water is demanded but the controller display does not show a numeric error code. This is a symptom guide for diagnosing ignition failure without a code. high	high
NO-HOT-WATER	Error 11, 12, 90 Diagnosis medium	medium
PRIORITY-LIGHT	The Priority indicator light on the Noritz remote controller is flashing or illuminated unexpectedly. Depending on the model and installation, this can indicate the unit is designated as the priority unit in a multi-unit installation, a service reminder is due, or an active fault needs attention. moderate	moderate
RESET	Step-by-step guide for performing a soft reset and a hard reset on Noritz NR and NRCP series tankless water heaters to clear error codes and restore operation. low	low
TROUBLESHOOTING	Catch-all troubleshooting guide covering the most common Noritz tankless water heater problems including no hot water, error codes, temperature issues, ignition problems, and condensate faults. moderate	moderate