BoilerFaultCodesTechnical description
Air pressure switch fault
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the fan isn't moving enough air to safely carry away exhaust fumes. The most common reason is a blockage in the flue pipe or a buildup of debris in the small tubes that measure air pressure, which prevents the boiler from firing for your safety.
This issue often crops up during periods of high winds, which can create back-pressure in the flue and interfere with the air pressure switch 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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