BoilerFaultCodesTechnical description
Fault in flame monitoring
What causes this fault?
This fault occurs when the boiler's internal computer is unable to verify that a flame is present, even if the burner has ignited correctly. It is usually caused by a dirty or corroded sensor that can no longer send a clear signal back to the control board, or a fault within the wiring and electronics that manage safety checks. Consequently, the boiler shuts down because it cannot confirm it is operating 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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