Noritz NRCP Eco TOUGH Code Er12
Flame loss. The burner lit and lost the flame. Noritz's remedies on this generation are to clean the intake air filter, and to make sure the main gas supply valve is fully open or have a professional check the gas supply pressure. That is a real change from the first generation, whose Er12 sends you to the burner window and the spare windows in the emergency kit — neither appears here. Manual reset.
Also displayed as: 12, E12
Call a proThe verdict
Call a licensed plumber
Clean the air filter and confirm the gas valve is fully open, not just partly. Those are both yours. Gas supply pressure is the remaining item and Noritz says outright to have a professional check it.
Typical cost: $0–$700
US estimate for parts and labor. Prices vary by region and by who does the work — see how we estimate costs.
What the manual says
The meaning above is transcribed from the manufacturer's diagnostic documentation for the NRCP Eco TOUGH — not averaged across the brand.
Source: Noritz Service Manual — NRCP1112-DV / NRCP982-DV Eco TOUGH (Rev. 05/19) (p. 58), read Sep 2026 — the manufacturer's own documentation for this exact series.
What you can safely check
Before anything else: if you smell gas, stop here, leave, and call your gas utility.
- Clean the intake air filter.
- Check the main gas supply valve is fully open — Noritz specifies fully, and a partly open valve starves the burner under load.
- If it persists, call a licensed professional to check the gas supply pressure.
Frequently asked questions
Another Noritz page mentions replacing a burner window for Er12. Does mine have one?
That guidance is from the first-generation NRCP manual, for the NRCP111-DV and NRCP98-DV. Noritz does not give it for the Eco TOUGH — this manual's remedies are the air filter and the gas supply. Do not go looking for a part your manual does not send you to.
Code Er12 on other Noritz series
Other Noritz series report code Er12 under the same fault name, but each manual is transcribed separately and they do not read alike:
Don't confuse this with
2 other Noritz NRCP Eco TOUGH codes point at flame detection too. They are the same symptom reported from a different place in the unit, so which one the display shows is what tells you where to look: