BoilerFaultCodesYour boiler's internal air system is failing to move waste gases out of the flue, which is preventing the unit from firing up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The diagnostics will indicate the nature of the fault to assist a speedy and effective repair
What causes this fault?
This fault occurs when the boiler's internal computer detects that the fan is not spinning at the correct speed or has failed to start entirely. The most common reasons are a build-up of debris within the fan motor or a failure in the electrical signals sent between the control board and the air pressure sensor.
High winds during winter storms can occasionally cause back-pressure in the flue, which creates extra resistance for the fan and triggers this safety shutdown.
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 Fan (If fitted) — no call-out fees, no surprises.
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