BoilerFaultCodesYour boiler has detected a safety concern or internal failure and has shut itself down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault lock-out conditions
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the burner has failed to light or maintain a flame safely. The most common reasons include a lack of gas reaching the burner, a worn-out ignition spark, or the control board losing track of the combustion process.
This issue is more frequent during the first cold snap of winter when components that have sat idle all summer are suddenly forced to work under high demand.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like A (number) — no call-out fees, no surprises.
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Potterton Powermax HE 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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