BoilerFaultCodesYour boiler has detected an issue with the fan that pushes exhaust gases out of your home, causing the system to shut down for safety.
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 can no longer control or receive speed signals from the fan that removes combustion gases. The most common reason is that the fan motor has physically burnt out or suffered a mechanical failure, though it can also be caused by loose electrical connections or a fault on the main control board. For safety, the boiler will stop firing immediately if it cannot confirm the fan is spinning at the correct speed.
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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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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