High Lockout
258 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler's internal computer has encountered a software or hardware communication error and has stopped working to protect itself.

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 fail to talk to each other correctly, leading to a total communication breakdown between the main brain and the control panel. The most common reason is a physical hardware failure on the main circuit board or a corruption in the software that manages the boiler's safety checks.

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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