2 Window air conditioners or 1 outside designated unit.

[pb57]

My shop is 56 X 34 with 12 foot ceiling and well insulated. I am planning on putting air in my metal shop and am not sure what would be better between maybe 2 window type units or one designated outside unit. I already have a new HotDawg propane heater unit so I wouldn't get the heater/air combo style furnace. Forgive my ignorance on these matters, I just want the best possible solution for cooling my shop. Its been really hot and humid here in NW Iowa and its time. thanks Paul

 

[59ctd]

With that large of an area I think you should go with one or two split style AC units. I am starting on planning a mini-split system since my portable shop AC is malfunctioning now. One advantage I see with the mini split system is the compressor is totally outside and thus greatly reduced noise levels in the shop. Also they do not block up the window view.

 

[SALIV8]

I would figure out my realistic needs and seriously consider:

forced air,
inverter window units,
non inverter window units,
multi head mini-split,
in no particular order.

many of the online retailers have their free load calc.
ecomfort.com, highseer.com, ComfortUp.com, also loadcalc.net

 

[theoldwizard1]

That is a HUGE space to cool ! My gut says you will need 4 LARGE A/C units in order to keep the temp below 75 on those 90+ days. Even with mini splits, my guess is you will need 2 compressors, each with 2 air handlers !

The only way to reduce cost is to divide that area and only condition part of it.

 

[Bert_]

That is a HUGE space to cool ! My gut says you will need 4 LARGE A/C units in order to keep the temp below 75 on those 90+ days. Even with mini splits, my guess is you will need 2 compressors, each with 2 air handlers !

The only way to reduce cost is to divide that area and only condition part of it.

You're so over dramatic...

Guy in town cools 60' x 160' 16' ceiling with 3 24,000 btu window units. Won't cool it to 65* but can do 75* no problem. Maybe 78* during extremely hot weather when it doesn't even cool down at night.

 

[pb57]

Thanks for all the replies, it gives me much to think about and research now. Paul

 

[PoorUB]

First thing I would do is decide if you really need to AC the whole shop. Perhaps you can move some equipment around, figure out the space you need, and put up a divider wall. If that is not and option you could go with window units, but you will need a few of them, two won't do it! A couple 2 or 3 ton mini splits might do it.

My buddy has a 30x60 shop. He put up a divider wall about half way so he has a 30x30 conditioned space and a 30x30 unconditioned/cold storage.

 

[Bert_]

I bet a single 24,000 would do a decent job. Just don't expect to turn it on only when you want to work.

Guy up the street from me put up a 50x100 w/14' ceiling for a hobby shop. Cools it with a 5 ton central a/c. Says it works great. (5 ton = 60,000btu)

I'm an hour NE of Sioux City so the weather is pretty much the same.

 

[Flatland Dave]

I'm looking at the same question 36 x 48 x 16. Too damn hot in the evenings to do anything. Mine calculates at a 4 ton unit.

 

[Pen & Wrench]

I'm no expert but having just replaced our forced air furnace and a/c unit for our home, I am a believer in getting something that works well. Our older unit just turned on and ran constant in even moderately hot weather, and couldn't seem to keep up. I made mention of this and they told me they already planned on a slightly larger and more efficient cooling unit. Now our a/c cycles on and off, even on very hot days, it doesn't have to work terribly hard to keep the house comfortable. My point is that for me, I want something that is designed to produce the cooling power needed for the space in mind. I'm not saying you should go overboard, but I would not skimp on too small a unit(s) that can't keep up either.

 

[PoorUB]

P&W, Comparing to the old unit can sometimes be a bad idea, after all you didn't change it out because it was working efficiently! It is very possible your old unit was not working as well as it should. A replacement of the same size may have worked better at cooling the house. Really you don't want the condensing unit to shut off much in extreme heat. If sized correctly it should run pretty much non stop in very hot weather.

When I was in the trade I would get calls from people that wanted a larger unit because theirs ran "all the time" in hot weather. first questions I would ask is if the temperature in the house was reaching the set point on the thermostat and also was it comfortable in the house. Many times both answers were yes, so in reality he equipment was sized correctly. If I replaced it and they insisted I would go up 1/2 ton. Air conditioning is one thing where too large is a bad thing.