BoilerFaultCodesYour boiler has identified a problem with the ventilation system and has shut down as a safety precaution because it cannot confirm that exhaust fumes are being cleared correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner in fault position. The air pressure switch is open at burner start or did not close on reaching the starting load. Check the air pressure switch and the connecting hoses.
What causes this fault?
This fault occurs when the boiler's internal safety sensors fail to detect the necessary airflow required to safely clear exhaust gases. The most common cause is a blockage in the flue or a failure in the fan assembly, which prevents the system from confirming it is safe to ignite the burner.
This fault can be more frequent during periods of high winds, as strong gusts can occasionally interfere with the air pressure balance within the flue system.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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