Low
358 on Worcester Bosch Greenstar Heatslave II

Your boiler is automatically moving a internal valve to keep it from sticking, which is a normal maintenance feature rather than a fault.

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

Three way valve anti-seize: Anti-seize operation. If the diverter valve has not moved in 24 hours, the valve is operated to prevent seizing, duration approximately 10seconds.

Engineer required

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

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