BoilerFaultCodesYour boiler is failing to detect its own flame correctly, causing it to shut down shortly after trying to start.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The correct working of the flame supervision is shown by the 'Burner On' neon going out and the ignition sequence starting up. After a short period the boiler will shut down.
What causes this fault?
This fault happens when the boiler's internal safety system fails to confirm that a flame has successfully lit. It is usually caused by a worn-out sensor that can no longer 'see' the flame, or a fault in the control board that prevents the ignition sequence from completing. When the boiler cannot verify it is burning gas safely, it shuts down immediately as a protective measure.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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