BoilerFaultCodesYour boiler has shut itself down for safety because a fault was detected, and it will not attempt to restart until it is manually reset.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler at Lock-Out
What causes this fault?
This fault occurs when the boiler fails to light or detect a flame after several attempts, leading the system to stop for safety. The most common reasons include a lack of gas supply, a worn-out ignition spark, or a sensor that can no longer tell if the burner is actually lit.
This fault is slightly more frequent during the first cold snap of winter, when internal components are put under sudden strain after being dormant all summer.
DIY fix possible
Press the reset button on the control panelEnsure your gas supply is turned on and you have credit on your meterCheck if other gas appliances in your home are working correctly
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 8 (Flashing) — no call-out fees, no surprises.
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Potterton Envoy System 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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