BoilerFaultCodesYour boiler has tried to start up several times but cannot establish a stable flame to begin heating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The boiler fails to light after 5 attempts
What causes this fault?
This fault occurs when the boiler's control system cannot confirm that a flame has successfully ignited after five attempts. It is usually caused by a worn-out ignition component that fails to create a spark or a faulty sensor that cannot detect the heat of the fire, leading the boiler to shut down for safety. In some cases, it may also indicate that gas is not reaching the burner at the correct pressure.
This fault is more frequent during the first cold snap of autumn when internal components that have been dormant all summer struggle to operate correctly upon restart.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like Detection Fault — no call-out fees, no surprises.
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