BoilerFaultCodesYour boiler's internal computer screen and main control board are having trouble talking to each other, meaning the unit cannot function.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: no communication to mainboard | connection error display mainboard
What causes this fault?
This fault occurs when the communication link between the boiler's control interface and its main brain is broken, preventing any commands from being processed. The most common reason is a loose or damaged internal wiring connection, though it can also be triggered by a power surge that has damaged the delicate circuitry on one of the electronic boards. Without this digital conversation, the boiler cannot safely ignite or operate.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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