BoilerFaultCodesYour boiler is unable to start up because the internal fan is not spinning at the correct speed required for safety checks.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Waiting for fan to reach ignition speed or stop
What causes this fault?
This fault occurs when the boiler's control system detects that the fan isn't spinning fast enough to safely clear waste gases from the combustion chamber. The most common reasons are a build-up of dirt inside the fan motor, a blockage in the air supply tubes, or a mechanical failure of the fan itself. Because the boiler cannot guarantee a safe flow of air, it will refuse to ignite as a safety precaution.
This issue is slightly more frequent in winter as the fan has to work harder to pull in denser, cold air, which can highlight an ageing motor or a partially blocked flue.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 1 — no call-out fees, no surprises.
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