Don't use refrigeration it will kill any profit you can attain from running gear. I posted in your other thread and as long as you have ambient temps below 40C (This is max) you just need to be sure you are removing the exhaust air.
Just do this, it's the best option by far. If possible, make it a 2 chamber: one cold chamber for the miners to intake and the other warm chamber to exhaust. Just make sure to extract all the warm air from the second chamber and you will be good and without AC.