Low
i02 on Worcester Bosch Greenstar 12i System

This code is simply a historical record of the last issue your boiler experienced and does not indicate an active, current 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

Last error: This can be viewed during normal operation. Displays the last diagnostic code with boiler status code.

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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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