BoilerFaultCodesTechnical description
Failure to light (could be a gas supply issue)
What causes this fault?
This fault occurs when the boiler tries to ignite three times but fails to detect a flame, causing the system to shut down for safety. The most common reasons are a temporary interruption in the gas supply, a blocked drainage pipe, or dirty internal components that can no longer create a spark.
This fault is significantly more common during freezing winter temperatures, as the external condensate pipe can freeze and cause a backup that prevents the boiler from lighting.
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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