Medium Warning
A-b2 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler has detected an issue with how quickly hot water is moving through the system, which may result in inconsistent water temperatures.

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

DHW flow rate: Hot water flow rate

What causes this fault?

This fault occurs when the boiler's internal sensors detect an unusual or inconsistent flow of water when you turn on a hot tap. It is usually caused by a physical blockage in the flow turbine, a build-up of limescale within the heat exchanger, or a communication error between the electronic sensor boards.

Engineer required

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

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Related fault codes

A-b4View →228View →

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