BoilerFaultCodesYour boiler's fan has failed or is not spinning correctly, which means the appliance cannot safely clear exhaust fumes and has shut down as a result.
Book a Gas Safe engineer within 24–48 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 internal computer detects that the fan is not spinning at the required speed to safely expel exhaust gases. The most common reasons are a mechanical failure of the fan motor itself, a loose connection in the internal wiring, or a fault on the main control board failing to send power to the fan.
This fault is slightly more common in winter when boilers are under heavy load, as the fan has to run more frequently and at higher speeds, which can cause an ageing motor to seize.
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 F3 — no call-out fees, no surprises.
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