Noritz NRCP Code Er29
Air pressure switch fault. The air pressure switch is not reporting what the unit expects. Noritz's remedies point at everything that can restrict the air and exhaust path: the exhaust pipe free of obstructions, a clean intake air filter, a condensate trap or pipe that is not clogged, and a condensate line that slopes downward.
Also displayed as: 29, E29
Call a proThe verdict
Call a licensed plumber
Three of the four checks are yours and free — the terminal outside, the air filter, and the condensate line. Do those first, because they are the common causes. What you should not do is start opening vent joints, which is where this stops being a homeowner job.
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 exhaust terminal outside for snow, leaves, a nest or anything built against it.
- Clean the intake air filter.
- Follow the condensate line and check it is clear, unfrozen and sloping downhill the whole way with no sagging loop.
- If all three are clear, call a licensed professional rather than taking vent sections apart.
Code Er29 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 switch 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: