BoilerFaultCodesYour boiler is currently struggling to light the flame it needs to provide heating and hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: ignition
What causes this fault?
This fault occurs when the boiler attempts to start up but fails to establish or detect a flame. The most common reasons include a worn-out ignition probe that can no longer create a spark, or a gas valve that isn't opening correctly to let fuel into the burner.
This issue can be more frequent during the first cold snap of autumn when internal components that have been idle all summer are suddenly forced to work under high demand.
DIY fix possible
Check that your gas supply is turned on at the meterIf you have a pre-payment meter, ensure you have active credit availableTurn the boiler off and back on again to trigger a resetCheck if other gas appliances in your home, such as a hob, are working correctly
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 S.23 — 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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