BoilerFaultCodesYour boiler has lost its flame while trying to run, which means it cannot heat your water or your radiators.
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 board detects that the flame has gone out unexpectedly while the unit is firing. The most common reasons are a restricted gas supply, a build-up of carbon on the ignition sensors, or a faulty gas valve failing to maintain the correct flow of fuel.
This fault is more frequent during extreme cold spells, as frozen external gas meters or pipes can restrict the pressure needed to keep the flame stable.
DIY fix possible
Check that your gas supply is turned on at the meterIf you have a prepay meter, check that you have enough creditPress the Reset button on the boiler displayEnsure your external condensate pipe hasn't frozen in very cold weather
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Fn — 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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