Medium
CA on Worcester Bosch Greenstar System

Your boiler has detected that water is flowing through your heating system faster than the pump can safely manage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Flow rate too high.

From this model's manual
Verified against the Worcester Bosch Greenstar System 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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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