BoilerFaultCodesWhat the manual says
Manufacturer manualSystem fault boiler electronics / basic controller
From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life Style installation & service manual, page 76.
What causes this fault?
This fault occurs when the boiler's main control board experiences a critical internal communication failure or a software glitch. It is usually caused by a component failure within the circuitry or an electrical surge that has corrupted the board's ability to process data. In some cases, loose or damaged wiring connections between the internal modules can also trigger this shutdown.
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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