Technical description
Faulty cable loom | Faulty or incorrect loom fitted
What causes this fault?
This fault occurs when the boiler's internal computer stops receiving the correct electrical signals from the main wiring system. The most common reason is that the plastic connectors have vibrated loose over time or the wires themselves have developed a break or short circuit. Because the control board cannot safely communicate with the various parts of the boiler, it shuts down as a safety precaution.
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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