BoilerFaultCodesYour boiler's main internal computer has developed a serious communication error and cannot operate, often because it has been exposed to water or has suffered an electrical failure.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Unidentified light indication; control board likely wet, damaged, or malfunctioning.
What causes this fault?
This fault occurs when the boiler's main control board suffers a critical internal failure and can no longer process data to operate the system. The most common cause is water ingress from a leaking internal component dripping onto the electronics, or a power surge that has damaged the sensitive electrical tracks on the board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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