BoilerFaultCodesYour boiler is performing a routine safety check by running the fan before the burner ignites.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: fan pre-run
What causes this fault?
This status occurs when the boiler prepares for ignition by clearing out the combustion chamber. The fan spins up to ensure there is a safe flow of fresh air and to remove any residual gases before the burner light. It is a fundamental part of the boiler's start-up sequence and not a sign of a mechanical failure.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like S.11 — no call-out fees, no surprises.
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