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 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 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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