Medium
Ad on Worcester Bosch Greenstar 25i (ZWB 7-25)

Your boiler has lost the connection to the sensor that measures the heat inside your hot water storage tank, so it cannot accurately tell when the water is hot.

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

Cylinder temperature sensor not detected

Engineer required

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

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