BoilerFaultCodesYour boiler is staying in a cooling-down phase for too long because the fan is still running after it should have stopped.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: fan overrun
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is still spinning even after the heating cycle has finished and the cooling period should have ended. The most common reason is a communication error between the main circuit board and the fan, or a mechanical stickiness within the fan motor itself that prevents it from stopping correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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