Medium
103 on Worcester Bosch Greenstar CDi Compact

Your boiler is having trouble communicating with the heat sensor in your hot water cylinder, which may prevent your water from heating up correctly.

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

Fault 41 Temperature sensor T2 at bottom of solar cylinder faulty: Short circuit on the sensor lead

From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact installation & service manual.
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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