Napoleon manuals & error codes
Napoleon Astound Built-In: Error Codes, Quick Fixes and Manual
This page covers the Napoleon Astound Built-In electric fireplaces in the 50, 62, 74 and 96 sizes. The Astound FlexMount and SlimMount are different models with their own manuals.
What this unit is
The Astound Built-In is a current Napoleon built-in electric fireplace that works with the Napoleon Home App. When something's wrong, it shows a code on its display.
Error codes: what the display means
| Code | What it means | Safe thing to try |
|---|---|---|
| OH | The safety thermal switch has tripped (overheat) | Unplug it or switch off its breaker and let it cool for 15 minutes, then restore power. If it keeps happening, call a tech |
| E-1 | Temperature sensor fault | Call a tech. Napoleon says to consult a service dealer (temperature sensor check) |
| E-2 | Blower fault | Call a tech. Napoleon says to consult a service dealer (wiring or blower/heater assembly check) |
| E-3 | Heater fault | Call a tech. Napoleon says to consult a service dealer (wiring or blower/heater assembly check) |
| WIN | Open window alert: the room cooled sharply while heating (likely an open door or window), so the heater turned off to save power | Close the door or window, then clear the alert by pressing and holding X and OK on the remote while pointing it at the fireplace, or use the Napoleon Home App. If it keeps happening, call a tech |
Common problems
- It shows OH and stops heating. This is a safety cutoff. Unplug it or switch off the breaker, let it cool 15 minutes, and turn it back on. If it comes back, call a tech.
- E-1, E-2 or E-3. Napoleon's fix for these is a service visit (temperature sensor, blower or heater assembly), so call a tech.
- It shows WIN. That's the open-window alert, not a fault. Close the door or window and clear the alert from the remote (hold X and OK) or the app.
- Flames work but no heat. Check the heat setting in the controls or app first, then look for an OH or E-3 code.
When to call a tech
- Smoke, a burning smell, or a hot cord or plug (turn it off and unplug it or switch off the breaker first)
- OH that keeps coming back after the unit has cooled and nothing is blocking it
- Any heater, blower or sensor error (E-1, E-2, E-3)
Official manual
Napoleon hosts this manual on its own site. Check that the model number on your unit matches.
- Astound Built-In 50/62/74/96 (NEFB50AB, NEFB62AB, NEFB74AB, NEFB96AB): official manual
Still stuck? Book a $49 video call
A real fireplace tech can look at your Napoleon Astound Built-In with you over live video. A Quick Fix call is $49 for up to 15 minutes, and you see the price before you book.
Book a video call or find a local pro
Back to all Napoleon manuals and error codes
Error code meanings come from Napoleon's manual for this model (linked above). Napoleon is a trademark of its owner; this page isn't affiliated with or endorsed by Napoleon.
Tech Brain check 2026-11-02: code table and fixes match Napoleon Astound Built-In Series manual W415-4170 rev G-0, troubleshooting p.39; WIN alert added from the same page (KB copy: tech-brain/sources/napoleon-astound-builtin-W415-4170.pdf).