Low
358 on Worcester Bosch Greenstar 1000

Your boiler is automatically running a short maintenance cycle to prevent its internal pump from getting stuck while it's not currently being used.

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

Anti-seizing functn. active

From this model's manual
Verified against the Worcester Bosch Worcester Bosch Greenstar 1000 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.

What causes this fault?

Component protection active

Engineer required

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

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