Original message
| Lancelot
 |  "Humidity problem"
, posted Wed 1 Oct 08:02  
Hey guys, how you all 'doin? I have a question for all you experts in the field, I have a commercial fridge and the temperature is fine and stable, I have an average of 5 degres celcius in an 18 hours working operation, my target is between 2 and 8 celcius so that is ok for the customers...but, the humidity average is 97%!! The gaskets on the doors are brand new and well ajusted so could the problem be that the compressor is bringing down the temperature too fast ? This unit is working on r-134 and has a fan on the evaporator and it used to be a freezer. Thanks Again guys
Pierre Paquin
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Replies:
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| Schock Therapy
| "Re(1):Humidity problem" , posted Wed 1 Oct 23:55:
Refrigeration systems are dehumidifiers. It is something they do very well, hence the need to provide drainage to remove all of the water they condense out of the air. I'm not sure how you arrive at the conclusion that you have 97% RH. Usually the complaint is the opposite, commercial refrigerators with forced air evaporators tend to dry product out. That is why coolers designed for humidity sensitive product use gravity coils instead of fan coils.
Is your problem that there are water droplets forming on the inside of the unit? This will happen if your evaporator condensate pan is not draining properly. Also, if the unit used to be a freezer, did you disconnect the electric defrost heaters? If not, and you are still using the defrost timer, you will be creating alot of steam inside the box with every defrost cycle. Perhaps that is where your humidity is coming from?
A freezer can be converted into a cooler with no problem, but there are a few things that need to be changed. A properly set up cooler should not need a defrost timer at all, but if you do use one, you want to make sure you disable any active heating methods, be it hot gas or electric. You also want to rewire the unit so that the defrost timer shuts off the compressor, but not the evaporator fans; they should run constantly. Often there will be a heater in or on the condensate drain line as well. Make sure that is disabled, or it will act like a humidifier too!
It's only a shock if your not expecting it!
[this message was edited by Schock Therapy on Thu 2 Oct 00:04] |
| | Lancelot
| "Re(2):Humidity problem" , posted Mon 6 Oct 08:21
Well after a week-end with my data recovery gizmo in the fridge, I take it out this morning and recover the data to see that the humidity is still high even after I disconnect the heater in the drain pan ??? I'm gonna check my gizmo in another fridge to see if it works properly...see you later!!
Pierre Paquin
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| | Lancelot
| "Re(2):Humidity problem" , posted Thu 2 Oct 11:14
Thanks again my friend for your fast response and for the quality of it. I've put a data recovery gizmo in the fridge, that's how I got the humidity percentage. I went to check out the fridge myself and I noticed that it did have a defrost timer as well as a heater in the pan...so I disconnected the defrost timer and I'm going to check it again later on to see if the humidity is still a problem. This fridge is used to store blood samples,so the high humidity doesn't affect the products in it, it's just that the technician working there finds it annoying to wipe off the water inside all the time, like I said before I work in an hospital so sometimes we have to adapt the equipement to the laboratories needs.
Anyways, thanks again for you precious collaboration it is greatly appreciated.
p.s. I'll post the results soon
Pierre Paquin
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