BoilerFaultCodesTechnical description
Flame loss after 6 successive ignitions – gas supply line valve being open.
What causes this fault?
This fault occurs when the boiler successfully lights but the internal sensors fail to detect a steady flame, causing the system to shut down for safety. The most common reasons are a buildup of carbon on the sensing probes, a blockage in the flue, or an unstable gas supply that prevents the burner from staying lit.
This fault is more common during the first cold snap of winter, as increased demand can highlight underlying issues with the gas valve or moisture buildup in the sensing electrodes.
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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