Low
358 on Worcester Bosch Greenstar 4000

Your boiler is briefly running its internal pump to prevent internal parts from sticking while it is not currently in 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.

Technical description

Anti-seizing functn. active

Engineer required

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

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