BoilerFaultCodesYour boiler has tried to ignite but cannot establish a steady flame, meaning your heating and hot water will not work until the issue is resolved.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame failure - The burner has failed to light. This is a manual reset fault. To reset, press and hold the 'R' button for 2 seconds.
What causes this fault?
This fault occurs when the boiler's control system detects that the gas has not ignited or the flame has disappeared shortly after lighting. The most common reason is a worn ignition lead that can no longer create a spark, or a build-up of carbon on the sensor that tells the boiler the flame is safely lit.
DIY fix possible
Check that your gas emergency control valve is open and you have credit on your gas meterCheck if other gas appliances in your home (like a hob) are working correctlyPress and hold the 'R' button for 2 seconds to attempt a manual reset
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F — no call-out fees, no surprises.
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Potterton Envoy Plus 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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