let me first state my back ground and then the problem.
I have an electronics background working in a nuclear facility.
My wife has a Russian grocery store with one Hussman 3 door reach-in cooler , a 3 door beverage-air reach in freezer, and a small deli case made sometime in the 60-s( brand name cross country of Denver Colorado).
The problems are these. The beverage-air is a rattle trap. the hussman and the deli case work fine. Although I do not understand how the deli case works because I can not find a thermostat control. The only gage is a two scale Ranco unit read in kg/lbs with the words. cut out in minutes. cut in differential.
The defrost timer is disabled. But I have only had to defrost it one time in six months.
The next problem is the heat that all of these give off in a small store. In the winter that is fine. But (from ohms law power is equaled to volts times amps. http://www.the12volt.com/ohm/page2.asp) if you have a 230 volt device pulling 15 amps it like having a couple of space heaters kicking on and off at the same time you are trying to stay cool.
One solution was suggested that I move the compressors outside so the heat and noise would be outside. I thought perhaps I would build a small building to put them in. The question would be how large. My land lord is a dairy supply business so he does a lot of medium level refrigeration work on the farm. All of the refrigeration work will be done by him but i like to understand all things. What would be the pitfalls of having these compressors outside when it gets 40 below 0.