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

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

Technical description

Flow rate too high.

Engineer required

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

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