BoilerFaultCodesYour boiler is struggling to keep its flame lit, which means it cannot heat your water or radiators reliably.
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 internal sensor can no longer detect a steady flame after the burner has ignited. The most common reasons are a worn-out sensing probe that can't 'see' the fire, or an unstable gas supply that causes the flame to drift and extinguish prematurely.
This fault can be more frequent during extreme winter cold, as freezing temperatures can affect gas pressure or cause moisture to interfere with the ignition components.
DIY fix possible
Check that your gas emergency control valve is open and you have credit on your gas meter.Check if other gas appliances in your home, like a hob, are working correctly.Reset the boiler by turning the mode knob to 'RE' and then back to your desired setting.During freezing weather, check that the white plastic condensate pipe leading outside is not frozen.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 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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