Low
226 on Worcester Bosch Greenstar 12i System

Your boiler is displaying this code simply because a service device or diagnostic tool is currently plugged into it, which is normal during maintenance.

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.

Technical description

Service tool has been connected

Engineer required

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

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