BoilerFaultCodesYour boiler has lost communication between its internal control boards, meaning it cannot send or receive the signals needed to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: All Boilers
What causes this fault?
This fault occurs when the data link between the boiler's main control board and the front display panel is interrupted. The most common reason is a loose or damaged wiring connection between these two components, though it can also be triggered by a sudden electrical surge that scrambles the communication signals.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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