BoilerFaultCodesWhat the manual says
Manufacturer manualBreak in communication to the TR 2.
From this model's manual
Verified against the Worcester Bosch Greenstar 30he installation & service manual, page 45.
What causes this fault?
This fault occurs when the boiler's internal computer modules cannot talk to each other, similar to a loose connection between a computer and its monitor. It is usually caused by moisture affecting the electrical contacts, a vibrating wiring harness that has worked loose, or a physical failure of the central control board's circuitry.
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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