BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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