BoilerFaultCodesYour boiler's internal computer has lost contact with the main control panel, preventing it from starting up correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Break in communication
What causes this fault?
This fault occurs when the data link between the boiler's main brain and its control display is interrupted, meaning the components can no longer talk to each other. The most common reason is a loose or damaged connection on the internal wiring, though it can also be triggered by moisture ingress or a failure of the electronic chips on the circuit boards. Without this vital communication, the boiler cannot safety-check its systems and will refuse to ignite.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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