BoilerFaultCodesYour boiler has switched itself off because it detected that the internal fan stopped moving the air needed for safe combustion around while it was running.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Airflow stopped during operation
What causes this fault?
This fault occurs when the boiler's control system loses the signal that air is moving through the unit while the burner is lit. The most common reason is a mechanical failure of the fan motor or a blockage in the flue pipe that prevents the air from flowing at the required speed. In some cases, it can also be caused by a faulty sensor or electrical connection that fails to report the fan's movement to the main computer.
This fault is slightly more common in winter or during high winds, as the fan has to work harder to overcome external air pressure or potential debris dislodged by stormy weather.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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