BoilerFaultCodesYour boiler is unable to start because it cannot light the small pilot flame, meaning you will have no 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: Pilot fails to light. No gas supply.
What causes this fault?
This fault occurs when the boiler attempts to start up but the small pilot flame fails to ignite or stay lit. The most common reasons include a blocked pilot burner caused by dust buildup, a worn-out sensor that can no longer detect the flame, or a fault within the gas valve preventing fuel from reaching the burner.
This issue is frequently seen after the boiler has been switched off all summer, as debris or air can settle in the pilot assembly during periods of inactivity.
DIY fix possible
Check that your home's main gas emergency control valve is in the 'on' position.Verify if other gas appliances, like a cooker or hob, are working to confirm gas supply.If you have a prepaid gas meter, ensure you have sufficient credit and the meter hasn't locked out.
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 A.(1) — no call-out fees, no surprises.
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Potterton Kingfisher 2 RS60, RS80, RS100 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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