BoilerFaultCodesYour boiler has tried to ignite but failed, likely because gas isn't reaching the burner or the flame isn't being detected.
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 cannot successfully establish or detect a flame. The most common reasons are a lack of gas reaching the unit, a build-up of carbon on the ignition probes, or an internal component like the gas valve failing to open.
This fault is more common during extreme cold snaps, as external gas meters or regulators can occasionally 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 pre-payment meter, ensure you have sufficient credit available.Press the 'Reset' button (often indicated by a flame with a cross through it) to see if the boiler restarts.
Find a Gas Safe engineer
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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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