Medium
265 on Worcester Bosch Greenstar 8000 Style Combi

Your boiler is struggling because it is producing more heat than your home is currently ready to absorb, which usually happens when the internal flow of water is blocked or restricted.

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

Heat demand lower than energy supplied

From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life Style installation & service manual, page 76.
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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