BoilerFaultCodesTechnical description
Air pressure switch fault
What causes this fault?
This fault occurs when the boiler's safety sensors detect that the fan isn't moving enough air to safely vent exhaust gases out of the flue. The most common reasons are a blockage in the air pipes, a failing fan motor, or the internal pressure switch simply getting stuck over time.
This fault is slightly more common during periods of heavy wind or storms, as high pressure against the external flue pipe can interfere with the boiler’s ability to circulate air.
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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