BoilerFaultCodesYour boiler is trying to start up but the internal fan is not spinning properly, preventing the heating from firing up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan start-up error
What causes this fault?
This fault occurs when the boiler's control system sends a signal to the fan to begin spinning, but it fails to reach the required speed to safely start the ignition process. The most common reasons are a build-up of debris or moisture inside the fan casing, or a communication failure between the main control board and the fan motor.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like S.1 — no call-out fees, no surprises.
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