BoilerFaultCodesYour boiler has detected an issue with the way it is venting or drawing air, causing it to shut down for safety.
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
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 clear exhaust fumes or pull in fresh oxygen. The most common reasons are a blockage in the flue pipe outside, a build-up of debris in the internal tubes, or a mechanical failure of the switch that monitors air pressure.
This fault is more common during periods of high winds or extreme cold, as external debris can blow into the flue or ice can restrict the air intake.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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