High Lockout
1065 B on Worcester Bosch Greenstar 8000 Life/Style

Your boiler's internal water pressure sensor is not communicating properly with the control board, preventing the system from operating safely.

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

Pressure sensor defective or not connected – check pressure sensor connection as it may need replacing

What causes this fault?

This fault occurs when the boiler's brain loses contact with the sensor that monitors water pressure, often due to a loose wire or a physical failure inside the sensor itself. Without this vital data, the boiler shuts down as a safety precaution because it cannot confirm there is enough water to operate without overheating.

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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