Noritz NRCP Code Er65
Water control valve fault. The water control valve is not behaving. Noritz's remedy is one line — check the water control valve. This is the motorised valve that meters flow through the heat exchanger, and it is how the unit holds a set temperature as demand changes.
Also displayed as: 65, E65
Part replacementThe verdict
Replace a part
A moderately priced part inside the cabinet. The symptom to expect is temperature that will not hold steady rather than no hot water, because the valve that corrects for changing flow is the one that has failed.
Typical cost: $200–$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
- Note what the water is actually doing — too hot, too cold, or swinging — and tell the technician.
- Book a service call.
Code Er65 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: