High Lockout
1075 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler has stopped working because it thinks the internal heat sensor is damaged or has an electrical fault, preventing it from monitoring temperature safely.

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

Heat exchanger temp sensor short circuit

What causes this fault?

This fault occurs when the electrical signal from the heat exchanger's temperature sensor reaches an impossible level, usually because the sensor has failed internally. The most common reason is that the sensor has developed a short circuit, meaning it can no longer accurately tell the boiler how hot the water is, causing the system to shut down for safety.

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

1076View →

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