Noritz NRCP Eco TOUGH Code Er39
False flame detection. The unit believes it can see a flame when there is none. Noritz names this generation's version "false flame detection" and gives three remedies: clean the flame window, make sure the front cover is closed securely, and check the flame detection sensor. The flame window appears here rather than under Er12, which is where the first generation puts it. Auto reset.
Also displayed as: 39, E39
Call a proThe verdict
Call a licensed plumber
The front cover check is free and takes ten seconds — do it. The flame window and the sensor are inside a sealed combustion chamber, and a false flame signal is a safety fault because the decision to open the gas valve depends on that reading.
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.
- Check the front cover is fully seated and latched — Noritz lists it as a remedy for this code.
- If the cover is secure and Er39 continues, call a licensed professional for the flame window and sensor.
Code Er39 on other Noritz series
The same code number can mean something different on another series — make sure you're reading the page for your exact unit:
Don't confuse this with
2 other Noritz NRCP Eco TOUGH codes point at flame detection too. They are different components in different places, and ordering a part against the wrong one is the most common way this fault gets expensive: