Low
208 on Worcester Bosch Greenstar 30i

Your boiler is currently running at full power for a manual testing sequence and will not respond to your normal thermostat settings until this mode is turned off.

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

The boiler is in chimney sweep mode

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 small button with a 'flame' or 'bin' symbol on the control panel.Press and hold the button for at least 5 seconds.The display should return to showing the temperature or a green light, indicating it is back in normal operation.

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