BoilerFaultCodesYour boiler has stopped working because it cannot safely expel waste gases or verify that the internal fan is moving air correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Air flow fault - Air pressure switch / Fan fault
What causes this fault?
This fault occurs when the boiler's internal safety sensors fail to detect the necessary movement of air required to safely ignite the burner. The most common reason is a malfunctioning fan that cannot spin fast enough or a blockage in the small tubes that measure air pressure, which prevents the boiler from confirming it is safe to operate.
This fault can sometimes occur during periods of high winds, as strong gusts can cause back-pressure in the flue that disrupts the sensitive air pressure readings.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F02 — no call-out fees, no surprises.
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