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  1. Akhil Agrawal
  2. Cold chain equipment
  3. Thursday, 22 December 2016

We are working with ILRs. While daily operations, it was found that there is formation of water droplets inside the device. We want to measure the amount of condensation taking place inside the device in a day. We also tried to calculate the Dew Point Temperature but not much useful.

Kindly suggest some method or way to measure the condensation.



Hi Akhil

Each ILR is different, there are some causes to the formation of water droplets: 1. The place where the device is located must be with air conditioning and far away of it. 2. the space to pass the cord of the thermometer´s sensor when pass between the lid and the rubber must be as small as it´s possible. 3. the ILR must be far away of doors and windows. 4. the sensor must be in the right place inside the ILR, when it doesn´t occur the compressor must work more and this it causes the water droplets.

Best regards


  1. more than a month ago
  2. Cold chain equipment
  3. # 1
Larry Schlussler Accepted Answer

Hi Akhil From my experience the quantity of condensation will not tell you anything about temperature swings in the

refrigerator. Are you having a problem with large temperatures in your refrigerator? Larry

  1. more than a month ago
  2. Cold chain equipment
  3. # 2
Murat Hakan Ozturk Accepted Answer

Hello Akhil,

It might not be easy to "measure" condensation accurately, unless you are willing to measure the volume of each water droplet forming inside the ILR.

You can try to "estimate" or "model" it but need control variables carefully as condensation will also depend on how many times you open the door of fridge, the level of humidity of the weather during during a time frame, your altitude, atmospheric pressure, type of your device (i.e. front vs top opening), temperatue outside and inside the refrigerator etc. etc...

However, if you can define your whole problem to someone who knows enough chesmistry or thermodynamics, he will be able to tell you theoritically the correlation of condensation with the temperature changes. And this might be even more insigtful than a measurement experiment with many variable to control.

Good luck,


  1. more than a month ago
  2. Cold chain equipment
  3. # 3
Gilles Ries Accepted Answer

Hello Akhill

You know humidity is going naturally into your ILR whenever the lid is opened. Carton packing boxes of vaccines also contain humidity which is then found back in your ILR.

You are saying the problem is water drops, right? Or is it ice?

You must know that water drops are a quite new problem that is linked to the fact that PCM (phase change material) are used in some ILRs nowadays in oprder to meet the required freeze protection for vaccines. The advantage of PCMs is, they have mostly a sublimation point of around 4°C, so they are never sub-zero, but as a consequence, the humidity inside the ILR is not transformed into ice, and remains on walls on floors and is subject to creation of funghi. Other systems still use water as a PCM, which is sub zero, removes the humidity effectively by turning it into ice first, and also can guarantee freeze protection for vaccines.

Hope this info helps


  1. more than a month ago
  2. Cold chain equipment
  3. # 4
Akhil Agrawal Accepted Answer

Hi Lary,

In the equipment, we are already measuring internal temperature and humidity. Still we are seeeing the water drops on the equipment wall. We want to measure the amount of condensation occuring in a day, so that we can associate with the temperature dip or rise.



  1. more than a month ago
  2. Cold chain equipment
  3. # 5
Larry Schlussler Accepted Answer

I may be able to help, however it would be useful to know why you want to measure the quantity of

condensation. Larry

  1. more than a month ago
  2. Cold chain equipment
  3. # 6
Andrey Kukharenko Accepted Answer

Hi Akhill,

I think you should count "absolute humidity" using Rh and Temperature data.

For example:

Temperature, C = +30

Relative Humidity, % = 60

Absolute humidity, kg/m3 = 0,0182 which is 18,2 gramm/cubic meter

Use this tools for more confident calculations:

or this simple one



  1. more than a month ago
  2. Cold chain equipment
  3. # 7

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