Medium
1022 on Worcester Bosch Greenstar 4000

Your boiler has lost the connection to the temperature sensor in your hot water tank, meaning it cannot tell how hot the water is.

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.

What the manual says

Manufacturer manual

Cylinder temp. sensor faulty or contact problems

From this model's manual
Verified against the Worcester Bosch Greenstar 4000 installation & service manual, page 74.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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