Medium
358 on Worcester Bosch Greenstar Ri

Your boiler is struggling to switch between heating your radiators and heating your hot water because the internal diverter mechanism is sticking.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Three way valve kick.

From this model's manual
Verified against the Worcester Bosch Greenstar Ri installation & service manual, page 37.
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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