High Lockout
263 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler’s internal computer has encountered a software or hardware error and can no longer communicate with the rest of the system.

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

System fault boiler electronics / basic controller

What causes this fault?

This fault occurs when the boiler's main control board experiences a critical internal communication failure, essentially meaning the 'brain' of the unit has become unresponsive. The most common reason is an electrical component failure on the printed circuit board or a loose connection within the internal wiring harness that prevents data from traveling between the sensors and the controller.

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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Related fault codes

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