Navien error codes
32 codes that Navien publishes for a tankless water heater, each quoted from the maker’s own manual or support page and explained on its appliance’s page. Pick the appliance, or type the code from the display: only Navien codes are searched here.
If you smell gas
Stop: do not reset, relight or check anything on this page. Navien’s own words, from the cover page of the NPE-2 User’s Information Manual, under “What to do if you smell gas”:
- Do not try to light any appliance.
- Do not touch any electrical switch; do not use any phone in your building.
- Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions.
- If you cannot reach your gas supplier, call the fire department.
Calling from a neighbor’s phone means leaving the building first. Source: NPE-2 Condensing Water Heaters User’s Information Manual (NPE-180A2, NPE-210A2, NPE-240A2, NPE-180S2, NPE-210S2, NPE-240S2; version 1.0, 2020), section 5.2 Understanding Error Codes, pages 17–18
Every Navien appliance we cover
| Appliance | Codes | Source |
|---|---|---|
| Navien tankless water heater | 32 codes | Navien, 1 document |
Navien tankless water heater error codes
32 codes from Navien. 22 of them are marked for a licensed professional; for the rest the page gives the checks the maker lets an owner do. Tap a code for its meaning:
Tankless gas water heater: do only the owner checks its manual gives for that code — open the gas and water shut-off valves, check a propane tank has gas, clean a filter the way the manual shows you, clear snow or debris from the vent ends outside, turn it off and on at the controller. Leave gas pressure, the burner, the gas valve, wiring and circuit boards alone. Everything else is for a licensed professional — in the manuals’ words, a qualified installer, service agency or the gas supplier. If you smell gas, do none of the checks: follow the maker’s gas-smell instructions at the top of the page. Two Navien models can use different codes: your model’s manual is the authority.
Sources
Every Navien code on this site comes from these pages, published by Navien and read on the date shown.
- Navien (tankless water heater): NPE-2 Condensing Water Heaters User’s Information Manual (NPE-180A2, NPE-210A2, NPE-240A2, NPE-180S2, NPE-210S2, NPE-240S2; version 1.0, 2020), section 5.2 Understanding Error Codes, pages 17–18 Checked 2026-09-29.