ITC-308 calibration isue

Hello, my 308 was siting in the corner for a year, now i need it back and it show 3c below atleast, can it lost calibration and if i calibrate it will be good or is it broken? how can i understand it

Hello,
If the ITC-308 reads 3 degrees lower than it actually is, it can be calibrated by setting CA = 3. After calibration, if it can detect the temperature correctly, it is working properly.