BoilerFaultCodesYour boiler's computer and its internal controls have stopped talking to each other, causing the unit to stop working for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Break in communication
What causes this fault?
This fault occurs when the boiler's main control board loses its electronic connection with the internal components or the display panel. It is usually caused by a loose wiring connection that has vibrated free over time or a critical hardware failure within the circuit board itself. Because the 'brain' of the boiler can no longer monitor safety sensors, it shuts the system down immediately to prevent damage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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