Low
1023 on Worcester Bosch Greenstar 4000

Your boiler is simply reminding you that it is time for its regular annual service to ensure it continues to run safely and efficiently.

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

Maximum run time including standby time reached | The service reminder message is present due to the maximum run time (boiler hours) being reached.

Engineer required

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

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