BoilerFaultCodesYour boiler has failed to light a flame, which is usually caused by a temporary interruption in the gas supply or a frozen condensation pipe.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Possible gas supply issue (failure to light)
What causes this fault?
This fault occurs when the boiler has tried to ignite several times but failed to detect a flame. The most common cause is a blockage in the condensation pipe or a temporary interruption in your gas supply, though it can also be caused by worn internal components like the ignition electrodes.
This fault is significantly more common during freezing winter temperatures, as the external condensation drain pipe can freeze and prevent the boiler from operating.
DIY fix possible
Check that your gas meter has credit and the isolation valve is openIf it is freezing outside, check if the plastic condensation pipe leading outdoors is frozen and thaw it with warm waterPress and hold the 'Reset' button for five seconds to restart the ignition sequence
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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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