BoilerFaultCodesYour boiler has detected a problem with the fan that clears exhaust gases, preventing the system from starting up for safety reasons.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Wiring from Fan to PCB insecure or lacks continuity, or failure of 230 VAC supply at Fan connections.
What causes this fault?
This fault occurs when the boiler's computer cannot detect that the fan is spinning fast enough to safely clear exhaust fumes from the building. The most common cause is a mechanical failure of the fan motor itself, though loose electrical connections or a fault with the main control board can also stop the fan from receiving power.
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 Fan Fault — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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