BoilerFaultCodesYour boiler has stopped working because it cannot light the flame, which means you currently have no heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner Lockout fault (gas supply, electrodes, flame sensor, or gas valve).
What causes this fault?
This fault occurs when the boiler attempts to start up but fails to detect a sustained flame after several attempts. It is usually caused by a lack of gas reaching the burner, worn-out sparking electrodes that can no longer create a light, or a dirty sensor that cannot 'see' the flame even if it is lit.
This issue often surfaces during the first cold snap of autumn when the boiler is pushed to work harder after sitting idle all summer.
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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A boiler cover plan would cover faults like FAIL POINT H — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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