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 internal computer chips fail to talk to each other correctly, leading to a total communication breakdown between the main brain and the control panel. The most common reason is a physical hardware failure on the main circuit board or a corruption in the software that manages the boiler's safety checks.
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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