Medium
2.6 on Worcester Bosch Greenstar R29 40 HE

Your boiler is struggling to maintain a consistent temperature because the difference between the actual water temperature and the target temperature is outside of the expected range.

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

Switching difference

From this model's manual
Verified against the Worcester Bosch Greenstar 25he 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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