BoilerFaultCodesYour boiler has tried to light several times but cannot establish a stable flame, meaning it cannot provide heating 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: Interruption of gas supply or flame sensing fault (5 second ignition attempts exceeded)
What causes this fault?
This fault occurs when the boiler fails to detect a flame after several attempts to spark, causing the system to shut down for safety. The most common reasons are a temporary interruption in your gas supply, a build-up of carbon on the ignition probes, or a component failure that prevents gas from flowing correctly into the burner.
This fault is frequently seen during extreme cold snaps, as the external condensate pipe can freeze and back up, preventing the boiler from lighting.
DIY fix possible
Check that your gas emergency control valve is turned on and that other gas appliances work.If you have a pre-payment meter, ensure you have active credit.Try resetting the boiler by turning the selector switch to the 'R' position for five seconds, then back to its original position.In freezing weather, check if your external plastic condensate pipe has frozen and needs thawing with warm water.
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