NIBE 233 fault code

What it means

Fan alarm from heat pump

Five unsuccessful fan start attempts. NIBE's listed causes: fan blocked or not connected.

Safety: Safe isolation before touching the fan.

UK models this code applies to

From the NIBE service literature we hold (NIBE S2125 installer manual IHB EN 2442-3 731742 — Alarm list) — not a scraped list.

Now the harder half: proving what caused it

233 names a symptom, not a root cause. In the app, the same code opens a guided investigation: what to measure first, the expected values for your exact model, and an honest verdict — including “nothing in this machine is broken” when that's what the readings say.