BoilerFaultCodesTechnical description
Flame not detected.
What causes this fault?
This fault occurs when the boiler attempts to light several times but the internal sensor cannot confirm that a stable flame has been established. The most common reasons include a lack of gas reaching the unit, worn-out ignition parts that fail to create a spark, or a build-up of carbon on the sensing probe. In many cases, it is simply caused by the burner becoming dirty or a blockage in the system that carries waste gases away.
This fault is more common in winter, as frozen condensate pipes are a leading cause of the boiler failing to ignite.
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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