BoilerFaultCodesTechnical description
Incorrect sensing of flame
What causes this fault?
This fault occurs when the boiler's internal computer detects an electrical signal signifying a flame even though the gas valve should be closed. The most common reasons are a moisture-damaged ignition lead causing a short circuit, a gas valve that is leaking slightly, or a faulty sensor that is incorrectly reporting a flame to the control board.
This fault can sometimes appear after periods of heavy rain or high humidity, as moisture ingress into the casing can interfere with the sensitive electrical signals of the flame sensor.
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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