BoilerFaultCodesYour boiler has tried to light but cannot detect a flame, meaning it has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No flame signal
What causes this fault?
This fault occurs when the boiler's control system fails to detect a flame after several attempts to ignite. It is often caused by a lack of gas reaching the burner, a worn-out ignition spark, or a dirty sensor that can no longer 'see' the flame even if it has lit.
This fault can be more common during the first cold snap of winter, as gas valves may stick after long periods of inactivity or external gas regulators may freeze.
DIY fix possible
Check that your gas emergency control valve is in the open positionIf you have a prepayment meter, ensure you have credit and the meter is activeCheck if other gas appliances, such as a hob, are working to confirm gas supplyReset the boiler by pressing the reset button for 2-3 seconds
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A boiler cover plan would cover faults like 4 — 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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