BoilerFaultCodesTechnical description
The burner did not light within 20 seconds. Refer to the 'Fault Finding' section.
What causes this fault?
This fault occurs when the boiler's internal computer tries to start the combustion process but cannot detect a stable flame within the safety timeframe. It is often caused by a lack of gas reaching the burner, a build-up of carbon on the spark electrodes, or a worn-out sensor that can no longer 'see' the flame even if it has lit.
This issue can occur more frequently during the first cold snap of winter, as gas valves may stick after sitting idle during the summer months.
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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