BoilerFaultCodesYour boiler's internal components are having trouble communicating with the main control board, preventing the system from starting up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Communication interrupted.
What causes this fault?
This fault occurs when the boiler's main control board loses its digital connection with internal components like the display or the heat engine sensors. It is usually caused by a loose connection in the internal wiring or a physical failure of the electronic circuit board itself, preventing the boiler from sending start-up commands. In some cases, moisture ingress or a power surge may have damaged the sensitive communication pins on the board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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