BoilerFaultCodesTechnical description
False flame lockout
What causes this fault?
This fault occurs when the boiler's internal sensors detect a flame after the burner has been told to switch off, or before it has even started. It is usually caused by a faulty sensing probe sending an incorrect signal to the main control board, or a leak inside the unit that has allowed moisture to interfere with the electrical components.
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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