BoilerFaultCodesYour boiler has lost its flame while running or failed to light, meaning it has shut down for safety and won't provide heat or 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: Flame loss
What causes this fault?
This fault occurs when the boiler's control system cannot detect a steady flame, causing it to shut down for safety. It is often caused by a lack of fuel reaching the burner, a dirty internal component that sensors the heat, or a blockage in the pipe that carries away waste liquid.
This fault is more common in freezing winter temperatures, as the external condensate pipe can freeze and prevent the boiler from lighting.
DIY fix possible
Check that you have credit on your gas meter and that the external gas valve is open.If it is freezing outside, check if your white plastic condensate pipe is blocked with ice and thaw it with warm water.Hold the 'Reset' button for three seconds to restart the ignition sequence.
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 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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