I am adding on to my shop, about 1500 sq, ft. with 12' ceiling.
I will insulate it and I am in Houston Texas so summers are typical 90 degrees.

I want to a/c this area, my choices are.

(2) 24,000 btu window units about $600 each. i can install ($1200)

or (1) 4 ton central a/c, havent got cost but i am guessing $4500 to $5000 installed.

so the qusetion is, what is more economical, sure the windows will cost less amd when they go (i typically get 8 to 10 years from one) just throw it away and buy another.

even if it saved me $200 a month for 6 months out of the year were use is alot, i will be 3 year to see a savings. In business if i can't pay for something is 1.5 years , it is typically not a good move.

 

Yer just about marginal on the tonnage with 4 tons and no room for a hot day that we occasionally get. Depending on yer east/west orientation, insulation and building construction, I'd move up some on the BTUs. In a shop environment, I always liked the window units. Some days you only have to run one and you can also get the heat pump types for a non-explosive type heat. If the unit goes bad, you still have one to run so you don't cook in the heat and a new unit can be slipped in the hole without having to hire an A/C tech. Most in that size range are fairly cheap so replacement is a much cheaper date not to mention the savings of being able to install it yerself. Might wanna consider the Friedrich 28000 BTU units. They're not cheap but near bulletproof. My brother has one in his house and it's going on 27 years old. It cools over 2400 sq ft but the house is completely covered by an oak tree.

 

thanks . about what i was thinking, down to the having 2 so if one goes out.