BoilerFaultCodesTechnical description
Operating errors or fault lock-out conditions are displayed as A (number) - see chart on Page 7.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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