Low
226 on Worcester Bosch Greenstar i

Your boiler is noting that a professional diagnostic tool has been plugged into it; this is an informational record rather than a sign of a mechanical failure.

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

Service tool has been connected In the blocking error history menu it records if the service tool has been connected

From this model's manual
Verified against the Worcester Bosch Greenstar I 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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