BoilerFaultCodesYour boiler has failed to light or maintain a flame, meaning your heating and hot water have stopped working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame loss
What causes this fault?
This fault occurs when the boiler's control system attempts to ignite the burner but fails to detect a stable flame. The most common reasons include a buildup of carbon on the sensing probes, an inconsistent gas supply, or a component failure that prevents the spark from starting the fire.
While this can happen year-round, it is more frequent during the first cold snap of winter when the boiler is under sudden high demand after sitting idle all summer.
DIY fix possible
Check if other gas appliances in your home, such as a hob, are working to confirm your gas supply is active.If it is freezing outside, check that your external condensate pipe hasn't frozen and if so, gently thaw it with warm water.Press the 'Reset' button on the front of the boiler display.
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 F2, FN or LN — 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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