Low
i01 on Worcester Bosch Greenstar 12i System

Your boiler is not actually broken; this code simply indicates it is currently in standby mode and waiting for a signal to provide heating or hot water.

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

Current status: Every operation and mode of the boiler has a related boiler status code. The boiler status code is displayed on the screen as a three figure number.

From this model's manual
Verified against the Worcester Bosch Greenstar 12i System 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

Check that your room thermostat or programmer is set to 'on'Increase the temperature setting on your thermostat to see if the boiler fires upEnsure your heating timer is scheduled correctly

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