Noritz NRCP Code Er40
Gas leakage. The appliance has detected gas leakage. Noritz's remedy column is two lines and neither is a repair: close the gas supply valve, and contact technical support. There is no diagnostic step, no resistance to measure and no part named, because at this point the correct action is not diagnosis.
Also displayed as: 40, E40
Emergency — stopThe verdict
Call a licensed plumber
Nothing to check and nothing to price first. The appliance is reporting gas leakage. Get out, shut the gas off only if the valve is safely on your way, and call the gas utility from outside. The range below is for the repair afterwards.
Typical cost: $0–$1,500
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.
Frequently asked questions
I cannot smell anything. Could Er40 be a false alarm?
It could be, and you still leave. Natural gas is odourised so most leaks can be smelled, but not all of them, not by everyone, and not at every concentration. The appliance has an instrument and you have a nose; when they disagree, act on the instrument.
Should I try to find the leak?
No. Noritz's own remedy list is two lines — close the gas valve, contact technical support — with no diagnostic step at all. Finding a gas leak involves instruments and a competent person, and looking for it means staying in a building you should have left.
Code Er40 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: