Split unit A/C?

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JAG2955
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Split unit A/C?

Post by JAG2955 »

So I've got this nice new garage. I want to air condition it, after seeing the prices on Big Ass Fans.

I believe the walls are insulated, based off of a small peek hole. Obviously I'd double-check what the R-value is prior to any installation. The ceiling is uninsulated, but there is a Tech-Shield or similar product on the back of the roof. 2x12" ceiling joists, by the way. I think that I could pull up the attic decking and stuff some batts in there pretty easily.

I think that a split unit AC is the way to go. I have a little bit of experience with them from deployment. 220v service is already in the garage. The doors are insulated.

Who's got some good info for me?
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Termite
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Re: Split unit A/C?

Post by Termite »

What's the size(sq. ft.) of your garage? A 'rule of thumb" is 1 ton per 500-550sq.ft for a "normally" insulated building.
Is the roll-up door insulated, and what direction does it face? Makes a difference.

I have an 8000 btu wall unit(115VAC) in my 12x24 shop/storage building. It will maintain 74F easily on a 95F day, with me reloading, wrenching, etc, but not while casting. Walls and ceiling have 4" fiberglass batt insulation.
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JAG2955
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Re: Split unit A/C?

Post by JAG2955 »

Whoops, can't believe that I forgot to post the size. 24x40 feet. Long axis is N-S. Doors open to the east and north (yay!). They are not metal roll-up doors, but more of the garage type with insulation on the back. The previous owner had it air conditioned with a window unit in the wall. Not for me. I want something more efficient and less noisy.

If it can maintain 74 degrees on a 95 degree day while I'm working out, I will be ecstatic.
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blackeagle603
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Re: Split unit A/C?

Post by blackeagle603 »

If you can find a local supply who sells the public (surprisingly difficult in our area) a self install pretty easy. Get ductwork and units situated and if need be a plenum fab'd at a local sheetmetal shop. I'd get an HVAC guy to do the copper lines and charge/bring up the system for you. I won't bother with that again.
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rightisright
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Re: Split unit A/C?

Post by rightisright »

For a garage your size, you are looking for 18-20K BTUs. I'd get two ductless 10K units and mount them to the ceiling (strategically placed, of course) and one outdoor condensor.

If you are handy with wiring, a split unit is fairly easy to install. But get a pro to charge it.
rightisright
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Re: Split unit A/C?

Post by rightisright »

Or you could save a lot of dough and get a 220v window unit like this: http://www.amazon.com/Frigidaire-FRA186 ... onditioner

Yes, it will be louder than a split unit. But many times, window unit noise can be attributed to poor installation. Making sure everything is tightly installed will dramatically cut down on vibration noise.
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Weetabix
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Re: Split unit A/C?

Post by Weetabix »

rightisright wrote:Or you could save a lot of dough and get a 220v window unit like this: http://www.amazon.com/Frigidaire-FRA186 ... onditioner

Yes, it will be louder than a split unit. But many times, window unit noise can be attributed to poor installation. Making sure everything is tightly installed will dramatically cut down on vibration noise.
We have one like that, and just the fan roar is deafening. I do have some vibration noise, too, but the fan!
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HTRN
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Re: Split unit A/C?

Post by HTRN »

Something else to consider - get a "whole house" dehumidfier. Bringing the humidity level down, makes higher temps more confortable.
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