BoilerFaultCodesYour boiler is failing to detect a flame after it tries to start, meaning your heating and hot water will not work.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: FAULT: THE BURNER LIGHTS BUT THEN GOES OUT. THERE IS NO FLAME DETECTED. / THE BURNER DOES NOT LIGHT AT ALL, BUT THERE IS AN IGNITION SPARK.
What causes this fault?
This fault occurs when the boiler tries to ignite but fails to confirm that a steady flame has been established, causing the system to shut down for safety. The most common reasons are a buildup of carbon on the sensing probes or a fault with the gas valve preventing fuel from reaching the burner. It can also be caused by an unstable gas supply or a worn-out ignition lead failing to carry the spark.
DIY fix possible
Check that your gas meter is turned on and you have credit if using a pre-payment meterCheck if other gas appliances, like a cooker, are working to confirm gas supplyPress the 'Reset' button (marked with a flame or 'R') on the boiler control panel
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F1 — no call-out fees, no surprises.
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Glow-worm 30ci 30si 35ci is discontinued — time for a new one?
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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