Garage Airconditioning

[yhprum]

I live in Arizona, it gets quite hot in the summer!
I was thinking of getting a used home airconditioning system that would be the outside pump, inside receiver type.
The idea is that I have a three car garage , it would cool down the garage quickly when I want to go out and do some work in the summer. All capacity would go to the garage.
Am I missing something? Why wouldn't this work?
Thanks Steve

 

[tojan19]

Well starting with the statement used isn't a good idea. If you can find a large house setup used it's probably a POS. They usually aren't replaced until busted. If they aren't solid copper construction (ie aluminum fins) than the lifespan is also decreased do to the differential expansion rates between the aluminum and copper. You'll always have leaks. Unless you really oversize the unit significantly don't think you'll be able to turn it on and the garage be cool in 20-30 min. I'm assuming your garage is already well insulated. If not this is where to start. Then figure out the AC. You can get some pretty well sized window units if that's an option. I've got a 2.5 car in SE Virginia and use an 18k btu. I do need to add insulation. I'm insulated to the room above and the wall with the house but that's it. Even on 95 deg days the AC will keep up if I start it BEFORE the garage heats up. I'd imagine that a 3 car w/ insulation could be served by a 20-24K with no problem. Does require 220v.