Medium
CA on Worcester Bosch Greenstar 25 HE Combi

Your boiler has detected that water is flowing through it faster than the system can manage, which may lead to inefficient heating.

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 through the heat exchanger is too high.

Engineer required

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

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Related fault codes

C6View →EAView →

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