BoilerFaultCodesYour boiler is failing to ignite the small starter flame, which means the main burner cannot catch light to provide heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check gas supply, air in gas line, pilot injector blockage, or supply voltage at pilot gas valve
What causes this fault?
This fault occurs when the small pilot flame fails to ignite or stay lit, preventing the main boiler from firing up. The most common reasons include a buildup of soot or debris blocking the tiny pilot hole, a worn-out probe that can no longer sense the heat, or a lack of gas reaching the burner.
This issue is more common after the boiler has been switched off all summer, as dust can settle in the pilot assembly or the gas line can develop air pockets during periods of inactivity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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