Nibe 290 Fault Code: Causes, Fixes & Repair Costs
What does the Nibe 290 fault code mean?
Alarm 290 on a NIBE heat pump is a fan alarm with an unusually specific documented meaning: the speed signal (tachometer signal) from the fan indicates the fan speed is zero — the controller commanded the fan and heard nothing back — and the compressor has stopped. Two stories fit a silent tachometer: the fan genuinely is not turning (obstruction, seized bearings, failed motor, no drive voltage), or it is turning and the feedback line has failed (broken tacho wire, connector fault, board input). The distinction is the entire diagnosis, and it takes an engineer thirty seconds of observation plus a multimeter to make it.
General guidance only — not a substitute for professional advice, and not certified by an heat pump engineer. Always have your specific appliance assessed by a qualified professional. Any heat pump work must be carried out by an MCS-certified heat pump engineer. If you notice a refrigerant leak, a burning smell or water leaking from the unit, switch it off at the isolator and call an MCS-certified heat pump engineer. Refrigerant work must be carried out by an F-Gas registered engineer.
Common causes
- Fan not turning — obstruction or seized motor Common
Ice, debris, or dead bearings stop the blade; the tachometer honestly reports zero. The homeowner check: is the fan visibly spinning when the unit runs?
- Tachometer feedback fault Sometimes
A broken feedback wire or corroded connector silences the speed signal from a perfectly healthy fan — the deceptive version, fixed cheaply once identified.
- Fan drive or board input failure Sometimes
No drive voltage reaching the motor, or the board input reading the tacho failing — settled by measurement at each point in the chain.
How to fix it
- Watch the fan during a run attempt DIY safe
From outside the guard, see whether the blade turns when the unit tries to start. Spinning fan + alarm = feedback fault; stationary fan = motor, drive or obstruction. That one observation halves the diagnosis — note it for the engineer.
- Switch off and check for obstructions DIY safe
With power isolated, look for ice or debris fouling the blade and clear what is reachable without dismantling.
- Have a suitably qualified heat pump engineer complete the documented checks heat pump engineer
The engineer will measure drive voltage at the motor and the tachometer signal back from it, test the bearings and windings, and replace fan motor, feedback wiring or board input as the measurements dictate. Any work on the sealed refrigerant circuit legally requires an F-Gas registered engineer; a NIBE-accredited (NIBE Pro) installer is the natural choice.
Parts you may need
- Fan motor (with tachometer feedback) · from £180
The exact spare depends on your boiler's GC number (on the data badge). Check this against the part before buying.
Typical repair cost
Expect to pay roughly £100–£400, depending on the underlying cause.
Frequently asked questions
What does alarm 290 mean on my NIBE?
The fan's speed-feedback signal reads zero — the controller thinks the fan is not turning — so the compressor stopped. Either the fan genuinely is not spinning (obstruction, failed motor) or it is fine and the feedback wire has failed. Watching whether the blade turns during a start attempt tells you which.
The fan IS spinning but the alarm shows — how?
Then the tachometer feedback has failed — a broken wire, connector or board input silencing the speed signal from a healthy fan. It is the cheaper version of this alarm and your observation is exactly what the engineer needs to hear when booking.
Why stop the compressor over a fan signal?
Because a genuinely stopped fan removes the heat source, and running the compressor without airflow drives refrigerant pressures out of range fast. With the feedback silent the controller cannot tell honest zero from broken wire — so it assumes the unsafe case, correctly.