High
223 on Worcester Bosch Greenstar 2000

Your boiler has lost its connection to an internal temperature sensor, meaning it cannot tell how hot the water is and has shut down for safety.

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

Interruption of the NTC cabling

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

224View →E9View →

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