High Lockout
F3 on Ideal Logic+ System

Your boiler has stopped working because the internal fan, which safely removes waste gases from your home, is not spinning correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Fan fault

What causes this fault?

This fault occurs when the boiler's control system detects that the internal fan is either spinning at the wrong speed or not moving at all. The most common reason is a mechanical failure of the fan motor, though it can also be caused by loose electrical connections or a communication error from the main circuit board.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F1View →L2View →

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