Medium
285 on Worcester Bosch Greenstar 1000

Your boiler has detected that the water returning to it is much hotter than expected, suggesting heat isn't circulating properly through your radiators.

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

Return temperature is too hot

From this model's manual
Verified against the Worcester Bosch Worcester Bosch Greenstar 1000 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.

What causes this fault?

Overtemperature at return

Engineer required

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

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