Technical description
Internal fault
What causes this fault?
This fault occurs when the boiler's internal computer brain fails to communicate properly with the other electrical components. It is physically caused by a data processing error on the main circuit board or a loose connection in the wiring that prevents the system from safely managing the heating process.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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