ADS1220: ADS1220 thermocouple measurement

Part Number:ADS1220

Hi

My customer has some queries need your help:

when touches the thermocouple the temperature increase quickly, put the thermocouple into the hotwater the  temperature increase about 10C. 

From TIDA-00168_Firmware what's the meaning of TCtemperature -= ADS1220TCdata?

Attached the customer's test code.(Please visit the site to view this file)

Please help check the attached the ADS1220 schematic.(Please visit the site to view this file)

Thanks

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