How long do cold packs last?
This is one of the most frequently asked questions from our customers. So let’s do some testing.
Validation of T-PACK 250g cold accumulators and a 4l thermal container of our production.
For the experiments we will use:
- 4l thermal container.
- T-PACK 250g cold accumulator – 2pcs
- Microcontroller for data processing – ESP32
- DS18B20 temperature sensor
- Imitation of a 4mm thick thermal package
Experiment conditions:
- Temperature outside the thermal box – +18
- Required temperature inside the thermal box +2 – +8
- Freezer -18
For more effective temperature distribution, we place one cold accumulator on the bottom, the other on top of the product. In our case, a temperature sensor. To isolate the temperature sensor from direct contact with the cold accumulators, we put on a thermal package. Close the lid and wait 24 hours. At the same time, we take temperature data every 10 minutes. In the table above, we see how the temperature inside the thermobox changed over 24 hours. Thanks to the unique formulation of T-PAK cold accumulators, cold accumulators do not have a rapid defrosting phase. The gel structure prevents rapid temperature loss. We see the initial temperature of the sensor as positive because the thermal package was at room temperature.


Our cold accumulators coped with the 24-hour test without any problems. In the graph we see that the T-PACK 250g cold accumulators are able to maintain a temperature regime of +2 – +8 for 26 hours. In the table above, we see the temperature inside the thermal container for 48 hours.


To extend the temperature regime, it is necessary to use a larger number of cold accumulators or increase the thickness of the thermobox wall.