Low
358 on Worcester Bosch Greenstar 12i System

Your boiler has performed a routine, automatic movement test on an internal valve to keep it from getting stuck while not in regular use.

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

Three way valve kick. If the 3-way valve hasn't moved in up to 48 hours, the valve will operate once to prevent seizure, (only available when using the optional integral diverter valve kit).

From this model's manual
Verified against the Worcester Bosch Greenstar 12i System installation & service manual, page 64.
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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