BoilerFaultCodesTechnical description
Flame disappears during operation.
What causes this fault?
This fault occurs when the boiler's control system successfully lights the burner but then loses the signal that a flame is present, leading to an immediate shutdown. The most common reasons include a buildup of carbon on the detection probe, a blockage in the drainage system that causes water to back up into the heat exchanger, or an incorrect mixture of gas and air.
This fault is more frequent during freezing winter spells, as a frozen external condensate pipe can cause water to back up and extinguish the flame.
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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