BoilerFaultCodesTechnical description
Air pressure switch error
What causes this fault?
This fault occurs when the boiler's internal safety sensor detects that the fan isn't moving air through the system correctly, which is vital for clearing dangerous exhaust gases. The most common reasons are a blockage in the flue pipe, a split in the small rubber sensing tubes, or a mechanical failure within the air pressure switch itself.
This fault can be more frequent during periods of heavy rain or high winds, as debris can be blown into the flue or moisture can enter the sensing tubes.
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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