Noritz water heater error codes
How to read the codes
Noritz tankless water heaters replace the temperature on the remote control with a number when they stop. Find the code below; codes 29, 92 and 93 apply to condensing models.
All Noritz codes
| Code | Meaning |
|---|---|
| 10 | Combustion abnormality (warning) Full guide |
| 11 | Ignition failure Full guide |
| 12 | Flame loss Full guide |
| 13 | Optional CO alarm device fault Full guide |
| 14 | Thermal fuse blown (severe overheat) Full guide |
| 16 | Outlet water temperature spiked too high Full guide |
| 20 | High limit switch tripped Full guide |
| 29 | Condensate drain problem (condensing models) Full guide |
| 67 | Air gas mixer (AGM) abnormality Full guide |
| 71 | Gas valve circuit abnormality Full guide |
| 90 | Combustion abnormality Full guide |
| 92 | Neutralizer near end of life (first warning) Full guide |
| 93 | Neutralizer at end of life Full guide |
Noritz codes fall into a few groups: ignition and flame (11, 12), combustion (10, 90), overheating (14, 16, 20) and condensate (29, 92, 93). Knowing the group tells you where to look first.
How to reset a Noritz code
Turn the unit off and back on at the remote, then open a hot tap. If the same code returns, the cause is still present. Some combustion codes require a specific reset procedure described in the manual.
What homeowners can check
- Gas supply and the propane tank level.
- Vent terminals outside, for blockages, snow or ice.
- The condensate line and neutralizer on condensing models.
- The inlet water filter.
- When the unit was last descaled.
When to call a contractor
Noritz recommends a licensed contractor for combustion, ignition and overheating codes that return. The fixes involve gas pressure testing, cleaning the inside of the unit and checking vent settings.
Common questions
How long do Noritz tankless water heaters last?
With regular descaling, a Noritz tankless heater can last around 20 years, much longer than a typical tank.