BoilerFaultCodesYour boiler has tried to ignite but failed to stay alight, which is often caused by a lack of gas supply or a blocked 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: Safety time to establish flame exceeded
What causes this fault?
This fault occurs when the boiler's control system attempts to light the burner but cannot detect a stable flame. The most common reasons are a temporary interruption in the gas supply, an ignition electrode that is too dirty to spark, or a blockage in the pipe that carries away waste water.
This fault is particularly common during freezing winter temperatures, as the external condensation pipe can freeze solid and prevent the boiler from firing.
DIY fix possible
Check that your gas supply is turned on and you have credit on your meter.During freezing weather, check if your external white plastic condensate pipe is frozen and thaw it with warm water.Press the Reset button for five seconds.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 133 — 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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