Low
208 on Worcester Bosch Junior 28i

Your boiler has been manually set to a testing mode used by engineers to check emissions and is not currently operating in its normal heating mode.

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

From this model's manual
Verified against the Worcester Bosch Junior 28i installation & service 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 'chimney sweep' or 'bin' icon on the control panel.Press and hold this button for at least five seconds until the light stops flashing.The boiler should return to normal operation; if it persists, try resetting the boiler using the main reset button.

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