BoilerFaultCodesYour boiler has stopped working because the burner isn't lighting correctly, likely due to a problem with the internal airflow or the ignition system.
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
What causes this fault?
This fault occurs when the boiler's control system detects that the burner cannot sustain a stable flame after several attempts. It is usually caused by a lack of proper airflow or an issue with the sensors that verify the flame is safe to stay on. The most common reasons are worn-out ignition components or a build-up of debris within the burner chamber that prevents a clean light-up.
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 1F — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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