High
223 on Worcester Bosch Greenstar 8000 Style

Your boiler has lost the connection to one of its internal temperature sensors, causing it to stop running 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

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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