BoilerFaultCodesYour boiler has failed to light a flame, which means it has safely shut itself down and will not provide heating or hot water until reset.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition failure / lockout (no gas supply, gas valve fault, ignition electrode fault, or flame detection fault)
What causes this fault?
This fault occurs when the boiler attempts to start but cannot establish or detect a flame after several tries. The most common reasons include a lack of gas reaching the burner, a buildup of carbon on the ignition parts, or a sensor that is unable to confirm the flame is safely lit.
This fault is more common during the first cold snap of autumn when internal components that have been idle over summer struggle to move or ignite correctly.
DIY fix possible
Check that your gas supply is turned on (check other gas appliances like your hob)If you have a prepay meter, ensure you have sufficient creditPress and hold the 'Reset' button for 2 seconds 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
A boiler cover plan would cover faults like LED1 and LED3 flashing, plus lockout — 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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