BoilerFaultCodesYour boiler has tried to light itself several times without success, meaning your heating and hot water will not work until it is reset or repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition failure – the boiler has attempted to light 5 times and not succeeded – check the gas supply is on
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a flame after several attempts to start up. The most common reasons include a lack of gas reaching the unit, a worn-out spark probe that can no longer ignite the fuel, or a blockage in the condensate drainage pipe preventing the system from firing safely.
This fault is frequently seen during periods of extreme cold, as the external condensate pipe can freeze and prevent the boiler from completing its ignition sequence.
DIY fix possible
Check that your gas emergency control valve is in the open positionCheck if other gas appliances in your home, such as a hob, are working correctlyPress and hold the 'Reset' button for three seconds to clear the faultEnsure your prepaid gas meter (if applicable) has sufficient credit
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E01 — no call-out fees, no surprises.
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Keston C36 is discontinued — time for a new one?
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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