Low
208 0 on Worcester Bosch Greenstar 30i

Your boiler is currently stuck in a professional test mode used by engineers to check emissions, often caused by a button being held too long or a recessed switch becoming stuck.

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

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 chimney sweep button (indicated by a small radiator/bin icon) on the control panel.Press and hold the button for at least 5 seconds until the display returns to normal temperature readings.If the code persists, try turning the boiler off at the main power switch for 30 seconds and then back on.

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