BoilerFaultCodesYour boiler has detected a problem with the fan that clears exhaust gases, preventing the unit from starting safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan error – a fan being blocked or excessive external air pressure.
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is not spinning at the correct speed or has failed to start entirely. The most common reasons are a physical blockage in the flue pipe, a build-up of debris inside the fan casing, or an electrical failure in the fan motor itself.
This error can occur during periods of high winds, as extreme gusts blowing directly into the external flue terminal can create enough back-pressure to prevent the fan from spinning correctly.
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 E15 — 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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