Medium Warning
1-A7 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler has detected an issue with a temperature sensor normally used in more complex heating systems, often meaning a sensor is faulty or incorrectly configured.

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.

Technical description

Temperature at hydraulic point: This service function will only be available, if service function 2-A1 is activated.

What causes this fault?

This fault occurs when the boiler's control system loses communication with a specific temperature sensor used to monitor water flow in larger or multi-zone systems. The most common reason is a physical failure of the sensor's internal components or a loose connection in the wiring harness that links the sensor to the main circuit board.

Engineer required

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

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