High
1-A2 on Worcester Bosch Greenstar 8000 Life Combi

Your boiler has detected an internal communication error or a software glitch that is preventing the system from starting up safely.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Current fault: Fault code (table 10.1.2)

From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life Style installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's main control board loses touch with the internal components it needs to manage, often due to a breakdown in electronic communication. The most common reason is a malfunction within the Printed Circuit Board itself or a loose connection in the wiring harness that carries signals throughout the unit. Because the 'brain' of the boiler can no longer verify that it is safe to operate, it stops the system from firing up.

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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