BoilerFaultCodesYour boiler was working but the flame has gone out unexpectedly, often due to an interrupted gas supply or a blockage in the drainage 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 extinguished
What causes this fault?
This fault occurs when the boiler successfully lights but the flame is lost unexpectedly during operation. The most common reasons are an interruption in the gas supply, a blocked condensate drainage pipe, or a build-up of carbon on the sensing electrodes which prevents the boiler from 'seeing' the flame.
This fault is particularly common during freezing winter temperatures, as the external condensate pipe can freeze and cause the boiler to shut down for safety.
DIY fix possible
Check that your gas emergency control valve is open and you have credit on your meter.If it is freezing outside, check if the plastic condensate pipe leading outdoors is frozen and thaw it with warm water.Press the 'Flame/Cross' reset button for one second to see if the boiler restarts.
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A boiler cover plan would cover faults like F.29 — no call-out fees, no surprises.
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