BoilerFaultCodesTechnical description
Communication error
What causes this fault?
This fault occurs when the boiler's main control board loses its electronic connection with the display or other internal components. The most common reason is a loose or damaged wiring loom between the parts, or a hardware failure on the circuit board itself that prevents signals from being sent. Because the components cannot 'handshake' to confirm everything is safe, the system shuts down for protection.
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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