Low
208 on Worcester Bosch Greenstar 8000 Style Combi

Your boiler has been accidentally switched into a specific testing mode used by engineers to check emissions, which is why it is ignoring your normal heating and hot water settings.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Chimney sweep demand

From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life Style installation & service manual, page 75.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Locate the wrench or chimney sweep icon on your boiler's control panel.Press and hold the chimney sweep button for several seconds until the indicator light goes out.Restart the boiler using the reset button if it does not immediately return to normal operation.

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