Noritz tankless water heater code Er39
Your series decides which reading applies. Across the 2 Noritz series documented here, code Er39 is listed as flame detected after the gas valve closed (1 series) and false flame detection (1 series). Find your series in the table below, where those readings route to a professional.
What code Er39 means on each Noritz series
| Series | What it means | Verdict | Typical cost |
|---|---|---|---|
| NRCP | Flame detected after the gas valve closed | Call a pro | $0–$700 |
| NRCP Eco TOUGH | False flame detection | Call a pro | $0–$700 |
Each row opens the full page for that generation. We hold manuals for NRCP and NRCP Eco TOUGH, and each one gets its own reading of code Er39 — what Noritz documents, what you can safely check yourself, and what the repair should cost.
What each manual actually says
The table above compares 2 series in four columns, which is enough to route you and not enough to explain anything. This is the Noritz wording behind each row, one entry per manual, so you can see where the 2 readings of code Er39 agree and where they part company.
NRCP — Flame detected after the gas valve closed
The unit shut the gas valve and still saw a flame signal. Noritz's remedies are to make sure the front cover is closed securely and to check the flame sensor voltage, which should read 5 VDC when the flame is off. The front cover appearing in a flame-detection remedy is not an accident — this is a sealed-combustion appliance and the cover is part of the air circuit.
NRCP Eco TOUGH — 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.
Does it matter which Noritz you have?
NRCP and NRCP Eco TOUGH all route code Er39 the same way: a professional, at $0–$700. That makes it one of the Noritz numbers you can act on before working out which unit you own.
Which Noritz do you have?
On the 2 series that report code Er39, the model number on the rating label starts NRCP — match yours against the 4 listed below. You can also use the full model-number decoder.
Where this comes from
Source: Noritz Service Manual — NRCP111-DV / NRCP98-DV (Rev. 09/19) (p. 62), read Sep 2026 — the manufacturer's own documentation for this Noritz range.
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 Noritz range.
Parts, guides and symptoms behind code Er39
Code Er39 on these 2 Noritz series points at 2 parts and 2 symptoms, each named by the manufacturer's own procedure for this code.