BoilerFaultCodesYour boiler's electronic control board is having trouble communicating with the flame sensor, meaning the system cannot safely confirm if the burner is lit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame amplifier input/output fault
What causes this fault?
This fault occurs when the boiler's main control board loses the ability to correctly process the signal from the flame sensor. The most common reason is an internal electrical failure on the printed circuit board, though it can also be triggered by damaged wiring or worn ignition electrodes that are no longer detecting the flame properly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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