High
E2 on Worcester Bosch Greenstar Si Combi / i System

Your boiler has detected a faulty internal temperature sensor, which means it cannot accurately monitor the water temperature and has shut down 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

CH flow NTC sensor defective.

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

E9View →C6View →

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