Low
208 on Worcester Bosch Greenstar 8000 Style

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.

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.

Technical description

Chimney sweep demand

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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