BoilerFaultCodesYour boiler has stopped working because it cannot light the gas burner to provide heating or hot water, usually because the gas supply is interrupted or the ignition spark has failed.
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 light but fails to detect a flame after several tries, forcing the system into a safety shutdown. The most common reasons are an interruption in the gas supply, a build-up of carbon on the ignition probes, or a component failure that prevents the spark from starting the fire.
This fault is more common during the first cold snap of winter, as gas valves can occasionally stick after long periods of inactivity during the summer.
DIY fix possible
Check if your gas meter has credit or if other gas appliances in your home are working.Ensure the blue gas isolation valve under the boiler is in the 'open' position (aligned with the pipe).Press the 'Reset' button (indicated by a flame with a line through it) and hold for one second.
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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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