BoilerFaultCodesYour boiler has detected an issue with the part that pushes waste 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 cannot confirm that the fan is spinning at the correct speed to safely expel exhaust gases. The most common reasons are a mechanical failure within the fan motor or a build-up of debris in the small tubes that monitor airflow, preventing the boiler from firing up for safety.
This fault can be more frequent in the autumn or after high winds, as debris or nesting material can sometimes enter the flue and obstruct the fan's operation.
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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