BoilerFaultCodesTechnical description
Flue/Air pressure switch failure
What causes this fault?
This fault occurs when the boiler's safety sensors detect that harmful exhaust gases are not being shifted out of the flue correctly. It is usually caused by a blockage in the air pipes, a failing fan that cannot create enough suction, or a perished rubber tube inside the unit. The boiler shuts down immediately to ensure These fumes do not spill back into your living space.
This issue can be more common during periods of high winds, as strong gusts can sometimes interfere with the pressure balance required for the switch to stay closed.
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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