BoilerFaultCodesYour boiler is failing to light the gas burner, meaning it cannot provide heating or hot water until the issue is resolved.
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 Failure / gas supply interrupted, ignition failed or flame not detected
What causes this fault?
This fault occurs when the boiler attempts to ignite but fails to establish or maintain a steady flame. The most common reasons include a lack of gas reaching the unit, a worn-out ignition spark, or a sensor that can no longer detect the flame once it is lit.
This fault is notably common during extreme cold snaps, as the external condensate drainage pipe can freeze and back up, preventing the boiler from lighting.
DIY fix possible
Check if your gas meter has credit and that the gas isolation valve is open.Try to reset the boiler by turning the selector switch to 'R' for five seconds and then back to the on position.In freezing temperatures, check if the external white plastic condensate pipe has frozen and needs thawing with warm water.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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