BoilerFaultCodesWhat the manual says
Manufacturer manualAir pressure switch not proved.
What causes this fault?
This fault occurs when the boiler's internal safety sensor cannot detect the flow of air needed to clear away fumes. The most common reasons are a cooling fan that has become stuck or dirty, a blockage in the flue pipe outside, or small internal tubes becoming perishd or clogged with debris.
This issue is more frequent during periods of high winds or extreme cold, which can put extra strain on the fan or cause external flue obstructions.
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.
Avoid the next call-out bill
A cover plan would handle faults like 40° neon flashing: no call-out fees, no surprise bills.
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