BoilerFaultCodesYour boiler has stopped working because it cannot confirm that the fan is safely clearing waste gases from the system.
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 detected by diagnostic feature.
What causes this fault?
This fault occurs when the boiler's internal safety sensor fails to detect the correct flow of air required to safely carry away combustion fumes. The most common reasons include a buildup of debris in the fan or air tubes, a mechanical failure of the pressure sensor itself, or a blockage in the flue outside.
This issue can become more frequent during periods of high winds, which can create back-pressure in the flue and interfere with the air pressure sensor's readings.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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