Technical description
failing or unstable flame of main burner
What causes this fault?
This fault occurs when the boiler's control system cannot detect a steady flame after trying to ignite the gas. The most common reasons are a worn-out sensing probe that can no longer see the flame, or a faulty gas valve that isn't providing the correct amount of fuel to keep the burner lit safely.
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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