Low
309 on Worcester Bosch Greenstar 12i System

Your boiler is currently operating exactly as it should be, as this code simply indicates it is busy heating your radiators and hot water.

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

CH & DHW system are being heated

Engineer required

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

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