BoilerFaultCodesYour boiler has stopped working because it cannot light the gas to start the heating process.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The burner fails to ignite
What causes this fault?
This fault occurs when the boiler attempts to light the gas but fails to detect a flame after several tries. It is often caused by a worn-out ignition lead that can no longer create a spark or a faulty gas valve that isn't letting fuel into the burner. In some cases, a blocked flue or a problem with the internal electronics can also prevent the ignition process from completing.
This fault can be more common during the first cold snap of winter when components that have been idle over summer are suddenly put under heavy physiological strain.
DIY fix possible
Check that your gas emergency control valve is in the 'on' positionIf you have a pre-pay gas meter, check that you have sufficient creditPress the reset button (indicated by a flame symbol with a cross through it) for five seconds
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 Flexicom 18sx 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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