High
1075 on Worcester Bosch Greenstar 2000

Your boiler has detected an electrical fault with the sensor that tracks the temperature of the water inside it, causing it to stop working to stay safe.

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.

What the manual says

Manufacturer manual

Short-circuit heat exchanger temperature sensor

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 84.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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