BoilerFaultCodesYour boiler has stopped working because it cannot light the gas flame or it can't detect that the flame is lit.
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 (lockout) caused by no gas, no detection
What causes this fault?
This fault occurs when the boiler attempts to start up but fails to establish a flame after several attempts. The most common reasons include a lack of gas reaching the unit, worn-out spark electrodes that can no longer ignite the fuel, or a faulty sensor that fails to tell the boiler the flame is safely lit.
This fault is more common during extreme cold snaps, as external gas meters or regulators can sometimes freeze, restricting the flow of gas to the property.
DIY fix possible
Check if other gas appliances in your home, like a hob, are working to confirm gas supply.If you have a prepaid gas meter, ensure it has sufficient credit.Press the reset button on the boiler control panel once to see if it restarts.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 01 — no call-out fees, no surprises.
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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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