High
Blue Light Flashing on Worcester Bosch Greenstar 12i System

Your boiler has detected a general internal fault and has automatically stopped running to keep your system safe.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

A fault condition has occurred. To reset the boiler: Press the reset button for five seconds. When the reset is successful the reset button will no longer be illuminated and the blue light will stop flashing and remain constant.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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