Low
208 on Worcester Bosch 24/28/35 CDi MkII

Your boiler is currently set to a special testing mode used by engineers to check emissions, rather than a standard heating fault.

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 appliance is in chimney sweep mode. Chimney sweep mode is deactivated automatically after 30 minutes.

From this model's manual
Verified against the Worcester Bosch Greenstar Cdi Compact installation & service manual, page 65.
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

Wait 30 minutes for the boiler to automatically exit the mode.Alternatively, press and hold the 'Chimney Sweep' button (often indicated by a chimney icon) for several seconds to manually deactivate it.

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