Noritz NRCP Code Er72
Flame detected before the gas valve opens. The unit saw a flame signal before it had opened the gas valve. Noritz's remedies are to make sure the front cover is closed securely and to check the flame sensor voltage, which should be 5 VDC with no flame — the same pair it gives for Er39, at the other end of the firing cycle.
Also displayed as: 72, E72
Call a proThe verdict
Call a licensed plumber
Check the front cover is properly latched, because it is free and it is Noritz's first remedy. Past that, a false flame signal is a safety fault — the logic that decides whether it is safe to open the gas valve depends on that reading being honest.
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 — not averaged across the brand.
Source: Noritz Service Manual — NRCP111-DV / NRCP98-DV (Rev. 09/19) (p. 62), 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.
- If Er72 stays, call a licensed professional — the remaining check is a voltage measurement at the flame sensor.
Frequently asked questions
Er39 and Er72 look like the same fault. What is the difference?
Timing. Er72 is a flame signal before the gas valve opens; Er39 is a flame signal after it closes. Both mean the appliance believes it sees a flame that should not be there, and Noritz gives them the same two remedies — but the point in the cycle tells a technician which part of the sequence to look at.
Code Er72 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
3 other Noritz NRCP codes point at a valve 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: