BoilerFaultCodesYour boiler has lost its internal connection between the main control board and the display panel, meaning it cannot communicate with itself properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal link
What causes this fault?
This fault occurs when the boiler's internal computer brain loses its physical connection to the front display panel. It is usually caused by a loose or damaged ribbon cable, or a component failure on the main circuit board that prevents data from traveling between the two parts. Because they cannot 'talk' to each other, the boiler shuts down for safety.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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