High Lockout
254 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler's internal computer brain is experiencing a critical communication error or software glitch that is preventing it from running.

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 internal computer chips stop talking to each other correctly, effectively causing the system to freeze or crash. The most common reason is a hardware failure within the main control board or a loose internal connection that has disrupted the flow of data.

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

232View →253View →

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