BoilerFaultCodesYour boiler has stopped working because it cannot confirm that the fan is safely clearing waste gases from the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: A flashing indicator shows that the air pressure switch has not made.
What causes this fault?
This fault occurs when the boiler's internal safety sensor cannot detect the necessary airflow required to safely expel exhaust gases. It is usually caused by a failing fan motor, a blockage in the flue pipe, or a perished rubber tube that prevents the pressure sensor from triggering. Because the boiler cannot guarantee that carbon monoxide is being moved out of the building, it shuts down as a safety precaution.
This issue often surfaces during the first cold spell of autumn when a fan that has sat idle all summer struggles to spin up to the required speed.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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