Low
1018 on Worcester Bosch Greenstar 4000

Your boiler is simply reminding you that it is time for its annual service to ensure it remains safe and runs 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

Maintenance interval expired

Engineer required

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

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