BoilerFaultCodesYour boiler is failing to complete its initial safety check of the air fan before 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 pre-purge for 8 seconds.
What causes this fault?
This fault occurs when the boiler's control system attempts to spin up the fan to clear out old gases, but it doesn't receive the required signal that air is moving correctly. The most common reasons are a mechanical failure within the fan motor itself or a blockage in the small plastic tubes connected to the air pressure sensor. If the fan can't prove it is working safely, the boiler will refuse to ignite to prevent the build-up of dangerous fumes.
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 1 — no call-out fees, no surprises.
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Ideal Response SE is discontinued — time for a new one?
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