High
1076 on Worcester Bosch Greenstar 4000

Your boiler has lost its connection to the heat sensor, preventing it from knowing how hot it is, so it has stopped working as a safety precaution.

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 disconnected

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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