High Lockout
242 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler has experienced an internal electrical error that is preventing it from firing up to provide heating or hot water.

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

Boiler electr. system fault

What causes this fault?

This fault occurs when the boiler's control system detects an inconsistency in the electrical signals required to manage the burner safely. It is usually caused by a failure in the ignition components or a breakdown in the communication between the sensors and the main control board. If the boiler cannot confirm a safe flame is present, it will stop working as a safety precaution.

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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