BoilerFaultCodesYour boiler has stopped working because the internal fan is not clearing the fumes properly, which is preventing the heating from starting up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Air pressure switch fault (fan not running)
What causes this fault?
This fault occurs when the boiler's safety system detects that the fan isn't spinning fast enough to clear waste gases from the flue. It is often caused by a buildup of dust in the fan motor, a blockage in the small plastic tubes that monitor air pressure, or the fan motor failing entirely. Because the boiler cannot guarantee it is venting fumes safely, it will refuse to ignite as a protective measure.
This fault is more common in autumn and winter, as spiders or debris can block the external flue or internal tubes during the colder months, and the fan is under more strain when the heating is used frequently.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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