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)

Shared across the Greenstar 8000 Life range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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Avoid the next call-out bill

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Related fault codes

All 151 fault codes on the Greenstar 8000 Life Combi

Seeing a different code? Every code this model can display, in one place.

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