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View Full Version : Climate Chamber Cooling Suggestions



javs
29-03-2011, 03:06 PM
Ladies and Gentlemen,

Here is the situation: I have a basic climate chamber room approximately 11' X 23' X 8' that is insulated with 2" high density foam insulation panels. For testing purposes in the past we have needed to keep the room at a set temperature of 60 +/- 2 degrees Fahrenheit. We were able to do this using a basic in-window air conditioning unit that we modified to run a little cooler than normal. We mounted it in one of the chamber walls. The climate room in located inside a warehouse where the ambient temperature ranges from around 55 degrees Fahrenheit in the winter to 80+ degrees in the summer.
Some new tests may require us to maintain ambient temperatures inside the chamber of 44 degrees Fahrenheit and 14 degrees Fahrenheit. I am looking for a cheap and reliable way to make this happen. By cheap I mean less than $3K so we're talking about a very small budget. Unfortunately I don't get to make budget calls so before any of you tell me I'm being cheap, please realize I have little to no say in the matter. If it can't be done for that price, so be it, but I'm interested to hear from anyone who has constructive thoughts or advice.
One idea we considered was using a reefer unit like those used on cooled semi-trailers. I know there are a few electric reefer options, but most of them cost $10K and used ones are difficult to come by, although I've seen one or two for around $3.5K. We also wondered if it would be possible to modify a gas/diesel powered reefer unit to run on electricity without too much modification or rebuilding. We have 3-phase and potentially 1-phase input to work with. Any thoughts or input on this idea would be appreciated.
I'm sure alot of you have concerns about the way the room is insulated. While I will be the first one to admit that the test chamber is far from perfect, for now let's just assume that it will be sufficiently insulted and enclosed.

Thank you all for your time and consideration!

-Joel

Emmett
29-03-2011, 05:04 PM
A reefer unit is applicable, I have personally modified the controlls on several of these units for this very purpose. As to retrofitting a gas/deisel unit I have no experience in this area, however if the gas unit is a generator I don't see why you couldnt modify it.

javs
29-03-2011, 05:18 PM
Exactly what we thought...If the gas/diesel is used to power a generator which in turn powers the unit, why not just bypass the generator with electric power from an external source. But I spoke with one gentlemen from Thermo King who said that's not how the units work. I tried to do additional research, but I really struggled to find any schematics or drawings as to how the units operate/are powered...etc. If anyone with more extensive knowledge of these units can chime in, I would really appreciate further explanation.

frank
29-03-2011, 08:41 PM
If anyone with more extensive knowledge of these units can chime in, I would really appreciate further explanation.

Would you like me to transfer this to the Transport Section?

javs
29-03-2011, 08:55 PM
Well, I considered that originally, but since I wanted to leave the discussion open to possibilities other than reefer units I thought this was a better place to start. If it's alright I may post a similar thread in the Transport forum as well, but more focused on that particular avenue. In the meantime if anyone has any suggestions on other methods for cooling the chamber I would love to hear them! Thanks

-Joel