BoilerFaultCodesTechnical 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 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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