BoilerFaultCodesYour boiler has tried to light several times but has failed, likely because gas is not reaching the burner or the spark is not working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: 5 failed attempts at ignition
What causes this fault?
This fault occurs when the boiler's control system fails to detect a flame after five attempts to start. The most common reasons are a lack of gas reaching the unit, a worn-out spark electrode that cannot jump the gap to light the fuel, or a faulty gas valve that isn't opening correctly.
This fault is slightly more common during the first cold snap of winter when gas valves that have been dormant all summer can occasionally stick.
DIY fix possible
Check that your gas meter has credit and the isolation valve is openCheck if other gas appliances in your home, such as a hob, are working correctlyPress the 'Reset' button on the control panel to attempt a restart
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 A01 — 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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