BoilerFaultCodesYour boiler has stopped working because it cannot properly detect the flow of air needed to safely light the burner.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner blocked, fault in the air pressure switch
What causes this fault?
This fault occurs when the boiler's internal safety sensors cannot confirm that the fan is pushing enough air through the system to safely clear away exhaust gases. It is usually caused by a physical blockage in the air pipes or a mechanical failure in the pressure switch that monitors this airflow. Without this confirmation, the boiler will refuse to light the burner to prevent dangerous fumes from building up inside the unit.
This issue can occur more frequently during periods of high winds or heavy snow, which can physically obstruct the external flue terminal or cause pressure fluctuations that trip the sensor.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F7 — no call-out fees, no surprises.
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