BoilerFaultCodesYour boiler has failed to ignite or stay lit, meaning your heating and hot water have stopped working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler does not activate
What causes this fault?
This fault occurs when the boiler's control system cannot confirm that a flame has been successfully established after several attempts. The most common reasons are a worn-out component that senses the flame, a lack of gas reaching the burner, or a build-up of carbon deposits on the ignition parts.
This issue is more frequent during the first cold snap of autumn, as ignition components that have sat idle or were already weakened can fail when suddenly asked to work under higher demand.
DIY fix possible
Check if your gas supply is active by testing another gas appliance like a hob.Try resetting the boiler using the 'R' or reset button on the control panel.Ensure your system pressure is between 1.0 and 1.5 bar on the pressure gauge.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 35 — 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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