BoilerFaultCodesWhat the manual says
Manufacturer manualModule not detected.
From this model's manual
Verified against the Worcester Bosch Greenstar 12i System installation & service manual.
What causes this fault?
This fault occurs when the boiler's main control board loses its connection to a specific internal electronic component or plug-in module. The most common reason is a loose wiring connection or a hardware failure within the circuit board that prevents the various parts of the boiler from talking to each other. Because the control board can no longer 'see' all its necessary components, it chooses to shut down as a safety precaution.
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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