BoilerFaultCodesYour boiler has failed to light, which means it cannot provide the gas flame needed to heat your water and radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition fault
What causes this fault?
This fault occurs when the boiler tries to light but fails to detect a stable flame after several attempts. The most common reasons include a lack of gas reaching the burner, a failure in the spark system that ignites the fuel, or a blockage that prevents the flame from staying lit.
This fault is frequently seen during freezing winter spells, as the external condensate pipe can freeze and back up, preventing the boiler from successfully igniting.
DIY fix possible
Check that your gas prepayment meter has credit (if applicable).Ensure other gas appliances, like a hob, are working to confirm gas supply is active.During freezing weather, check if the external white plastic pipe (condensate pipe) is frozen and thaw it with warm water.Press the Reset button for five seconds to attempt a restart.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E133 — no call-out fees, no surprises.
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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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