High
238 on Worcester Bosch Greenstar 8000 Life Combi

Your boiler's internal computer has encountered a critical error and can no longer communicate with the rest of the system.

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

Boiler electronics faulty

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 suffers a hardware failure and stops sending data to other internal components. It is often caused by a sudden electrical surge or an internal short circuit that has damaged the delicate microchips on the circuit board. Without these clear signals, the boiler cannot safely coordinate the ignition and heating process.

This fault is more common following summer storms, as power surges from lightning strikes or grid fluctuations can damage the boiler's sensitive electronic circuits.

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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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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