Low
4-A5 on Worcester Bosch Greenstar 2000

Your boiler is simply letting you know that it has reached its scheduled running time and is now due for a routine service.

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

Inspection interval according to hours run: 10 ...60 x 100 hours.

Engineer required

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

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