BoilerFaultCodesYour boiler is struggling to light or cannot detect that a flame has started, so it has shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Poor flame signal. No flame signal at the end of the safety time.
What causes this fault?
This fault occurs when the boiler's internal computer tries to light the burner but fails to detect a steady flame within a few seconds. This is often caused by a worn-out ignition spark or a dirty sensor probe that can no longer 'see' the fire, but it can also happen if the gas supply is restricted or the condensate drainage pipe is blocked. Essentially, the boiler shuts down because it cannot confirm it is burning fuel safely and efficiently.
This fault is more frequent during freezing winter spells, as the external condensate pipe can freeze and back up, preventing the boiler from lighting.
DIY fix possible
Check that your gas prepayment meter has creditEnsure the gas stopcock is fully openReset the boiler by pressing the 'Reset' button for two seconds
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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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