BoilerFaultCodesYour boiler has tried to ignite three times but failed, meaning it has locked itself out for safety and you will have no 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: The boiler does not light after 3 attempts
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a flame after several attempts to start. The most common reasons are a temporary interruption in the gas supply, a blocked drainage pipe, or a build-up of carbon on the part that creates the spark. Because the boiler cannot confirm it is safely burning gas, it shuts down to prevent unburnt gas from escaping.
This fault is more common in freezing winter temperatures, as the external condensate drainage pipe can freeze and back up into the boiler, preventing ignition.
DIY fix possible
Check if your gas supply is active (e.g., check if a gas hob or other gas appliance works).Check if your gas meter has credit (for pre-payment customers).Press the 'Restart' button on the front control panel to reset the ignition sequence.
Find a Gas Safe engineer
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