High Lockout
250 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler's main internal computer has encountered a communication error and needs a reset to try and clear the glitch.

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 central control board and the internal display unit stop talking to one another properly. The most common reason is a temporary software glitch or a loose connection in the internal wiring that prevents the computer from sending commands to the heating components.

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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