Freezer Thermometer Calibration

Hi all,

 We have one THERMOMETER mounted outside the freezer but it is not effective. We purchased one and we wrapped it around one rack in the freezer. It was working well until recently when it started giving a result very far different from our reference thermometer. I am just wondering about what thermometer should be used for walk in freezer. Also how should the thermometer be calibrated? and also what should be the acceptable difference between reference and test reading?

Thanks,

Hi all,

 

 We have one THERMOMETER mounted outside the freezer but it is not effective. We purchased one and we wrapped it around one rack in the freezer. It was working well until recently when it started giving a result very far different from our reference thermometer. I am just wondering about what thermometer should be used for walk in freezer. Also how should the thermometer be calibrated? and also what should be the acceptable difference between reference and test reading?

 

Thanks,

Hi omoware,

The usual target IMEX is to monitor the warmest area in freezer although a knowledge of the temperature profile is useful for a static situation. Choice of monitoring instrument likely relates to yr financial resources, eg data loggers, bimetallic, thermocouple and how precisely you wish to know the temperature.

The usual procedure IMEX is to calibrate an isolated freezer monitoring instrument against a reference thermometer which is externally calibrated at the freezer temperature. (It's unfortunately not easy to set up internal reference thermometer temperatures around -18degC).

Hi omoware,

 

The usual target IMEX is to monitor the warmest area in freezer although a knowledge of the temperature profile is useful for a static situation. Choice of monitoring instrument likely relates to yr financial resources, eg data loggers, bimetallic, thermocouple and how precisely you wish to know the temperature.

 

The usual procedure IMEX is to calibrate an isolated freezer monitoring instrument against a reference thermometer which is externally calibrated at the freezer temperature. (It's unfortunately not easy to set up internal reference thermometer temperatures around -18degC).

Thanks Charles

The calibration procedure you described is exactly what we do but the difference has been more than +/_ 0.5, which I know to be the standard.

Regards,

Thanks Charles

 

The calibration procedure you described is exactly what we do but the difference has been more than +/_ 0.5, which I know to be the standard.

 

Regards,

Hi Omoware,

What kind(s) of "thermometer is/are being used"?

IMEX, air temperature is used for routine monitoring of environment in air blast freezers.

What is approx. day-by-day  max  difference in reading between 2 units at (I presume) ca -18degC air temperature ?

(Are you sure the 2 thermometers are sampling the same location ?).