Technical description
Wiring fault
What causes this fault?
This fault occurs when the boiler's internal computer loses the ability to communicate with its electrical components. It is physically caused by loose connections in the wiring harness or a failure in the circuit board that prevents signals from being sent correctly. In some cases, electrical interference or dampness on the wires can lead to these two specific codes.
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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