BoilerFaultCodesYour boiler has detected an issue with the internal fan, which is preventing the system from safely clearing exhaust gases and starting the ignition process.
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 control center is unable to communicate with or power the fan that removes exhaust gases. The most common reasons are a complete mechanical failure of the fan motor or a fault in the electronic circuit board that sends the signal to start. Without the fan spinning at the correct speed, the boiler will refuse to ignite for safety reasons.
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 F3 — 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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