BoilerFaultCodesYour boiler has tried to start up but failed to ignite the gas flame, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The burner did not light within 20 seconds. Refer to the 'Fault Finding' section.
What causes this fault?
This fault occurs when the boiler's internal computer tries to start the combustion process but cannot detect a stable flame within the safety timeframe. It is often caused by a lack of gas reaching the burner, a build-up of carbon on the spark electrodes, or a worn-out sensor that can no longer 'see' the flame even if it has lit.
This issue can occur more frequently during the first cold snap of winter, as gas valves may stick after sitting idle during the summer months.
DIY fix possible
Check that your gas prepay meter has creditEnsure other gas appliances in your home (like a hob) are workingPress the reset button once to see if the boiler restarts
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
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Ideal Mini HE 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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