BoilerFaultCodesYour boiler has failed to ignite and has shut itself down for safety, meaning you will not have any heating or hot water until it is reset or repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Appliance does not light & goes to lockout
What causes this fault?
This fault occurs when the boiler's control system attempts to light the burner but fails to detect a flame after several attempts. The most common reasons include a lack of gas reaching the unit, a worn-out component failing to create a spark, or a sensor that can no longer confirm the flame is safely lit.
This fault is more frequent during the first cold snap of winter, as gas valves can occasionally stick after being inactive during the summer months.
DIY fix possible
Check if your gas meter has credit and other gas appliances like the hob are workingPress the Reset button (indicated by a flame with a cross through it) for five secondsEnsure the boiler pressure gauge is between 1.0 and 1.5 barIf it is freezing outside, check that your white plastic condensate pipe hasn't frozen
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 Ultracom 24cx 30cx 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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