BoilerFaultCodesYour boiler has lit correctly but the flame has gone out unexpectedly, often due to a fuel supply issue or a blockage in the condensate pipe.
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 successfully ignites but cannot maintain a steady flame, causing the system to shut down for safety. The most common reasons include a temporary interruption in the gas supply, a dirty internal sensor that can no longer 'see' the flame, or a blockage in the drainage pipe that causes water to back up into the heat exchanger.
This fault is frequently seen during freezing winter spells, as the Keston's external condensate pipe can freeze solid, preventing the boiler from clearing waste fluid.
DIY fix possible
Check that your gas emergency control valve is open and you have credit on your meter.Check if the condensate discharge pipe (the plastic pipe leading outside) is frozen or blocked.Reset the boiler by pressing the 'Restart' button.
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A boiler cover plan would cover faults like L2 — 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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