BoilerFaultCodesTechnical description
Control box errors - possible faulty control box.
What causes this fault?
This fault occurs when the boiler's internal computer brain fails to communicate correctly with the safety sensors and ignition components. It is physically caused by a microchip failure or a corrupted circuit on the main control board, preventing the boiler from managing the heating process safely. The most common reason is general electronic wear and tear or a power surge that has damaged the delicate internal wiring.
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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