To A/C or not to A/C my work space

[weq92f]

We're into like day 4 now of 100+ degree days here with another several in a row to come. Tomorrow's expected high: 109.

My shop/garage is 740 sq/ft with 3 8ft doors made of 2 layers of inch and a half pine with a half inch backer board. There's living space above and a single rear facing door to the back yard. All the walls except for a 20 ft section facing east and about a 10 ft section facing north are insulated as they face into the house.

I'm thinking of buying a 14000 BTU, dual exhaust (hose), portable A/C unit. It's about 450 out the door for this thing: Honeywell MM14CHCS

When the temp outside at full sun all day is 105 in the evening around 5pm, the temp in the garage is about 95. This is with all doors closed all day.

You guys think I have a chance of bringing that temp down any with such a A/C unit?

Thanks,

-klb

[Willys_MB]

You might be better off with a swamp cooler. I think that AC unit will run your electricity bill through the roof. I'm not sure how power is there, but here PG&E destroys us.

The key to a swamp cooler to prevent that musky smell is you have to have a window open, but it works really well. They're used in large spaces like aircraft hangars. You can usually get a portable one at Home Depot this time of year for about the same price.

I have one and it follows me everywhere when I'm working. I even have it set up when I'm BBQing and I have my own little comfort zone when everyone else is dying.

[Willys_MB]

We get a late summer here, so coming in August and September we'll be in the same boat as you are now. For now at least, it cools off to 75 at night.

[Steeveedee]

If you have low humidity, a swamp cooler is the way to go. You will get about 10° off the temp, and the humidity will help you feel even cooler. If you live with high humidity, refrigerated air is the only way to go.

[weq92f]

My neighbor has one of those, big one, and it works great out side. Wife and I were outdoors on a date night couple days ago where an even bigger one was in use. I was really impressed with the cool air just blasting from it.

I worry about internal engine parts rusting and just getting too much moisture in the space.

-klb

[Willys_MB]

Originally Posted by weq92f

I worry about internal engine parts rusting and just getting too much moisture in the space.

That's the thing with the open window. A lot of people don't read the instruction manual that says you have to open a window to keep the humidity down.

That's a really good point about the humidity in his location. I didn't think of that since it's always really dry in my area.

[clay68c10]

Dallas may be too humid for it to work well, it’s dryer here in Denver and the swamp cooler we have in the shop isn’t always great. It doesn’t take much humidity to kill the effect.
When I worked for park place in Dallas, we had a/c in the shop. It worked well. The swamp cooled shops seemed hot.

[tdangle]

My vote is for the A/C over a swamp cooler. If you want to be cool, you will just have to pay. Way better than

[rockyrivermark]

Originally Posted by Steeveedee

If you have low humidity, a swamp cooler is the way to go. You will get about 10° off the temp, and the humidity will help you feel even cooler. If you live with high humidity, refrigerated air is the only way to go.

That's great advise. Ringing out the air is key here.
Here is cleveland we hit 90's with high humidity.
My shop is 1,200 square feet with 10' ceilings.
I have a 3 ton unit with truck line along ceiling.
Cools very nicely and pretty quick.

[Metaldoc]

A/C in the shop has been great, just insulate very well and it works great. I've got a window shaker. My is 72F all year long summer or winter.

[35boulder]

I'm in Dallas as well. I use a mitsubishi split air system in my shop. Works great and since its a heat pump as well i get heat when i need it in the winter. My shop in not insulated and i'm out here and staying cool. And they stand by their product as well...ask me how I know!

[A1971Blazer]

I bought a Frigidaire 25,000 BTU window unit...I'll be mounting it thru the wall on my addition at 20' x 36' x 12' ceiling.......highly insulated......
also has 16,000 BTU supplemental heat pump....
I just cannot work when it's hotter than two mice screwing in a wool sock...

[jocko]

Swamp cooler won’t work very well here in DFW area, especially between Jun and Sep. Since your shop isn’t gigantic, you’d probably be fine with what you’re considering or even with a dedicated non-portable unit.

[SIKKI-6]

Originally Posted by weq92f

We're into like day 4 now of 100+ degree days here with another several in a row to come. Tomorrow's expected high: 109.

My shop/garage is 740 sq/ft with 3 8ft doors made of 2 layers of inch and a half pine with a half inch backer board. There's living space above and a single rear facing door to the back yard. All the walls except for a 20 ft section facing east and about a 10 ft section facing north are insulated as they face into the house.

I'm thinking of buying a 14000 BTU, dual exhaust (hose), portable A/C unit. It's about 450 out the door for this thing: Honeywell MM14CHCS

When the temp outside at full sun all day is 105 in the evening around 5pm, the temp in the garage is about 95. This is with all doors closed all day.

You guys think I have a chance of bringing that temp down any with such a A/C unit?

Thanks,

-klb

Get yourself a Mini Split or get a condenser and air handler with about 5KW heat kit, run a flex duct to the upstairs room with a 12x6x6 box and a 12x6 side wall grill. Maybe for downstairs to make it look cool looking (industrial look) run a 7 or 8" spiral pipe with a couple of outlets 10x6 or 12x6 grilles.

[weq92f]

The deal I quoted turned out to be BS. It was a single pipe portable.

So I'm now looking at a Mr. Cool mini split from Cosco. These are marketed and warranted as DIY!

https://www.costco.com/Mr-Cool-DIY-1...100409871.html

I've got a vac pump and lines so I should be able to completely install this myself. Might have to borrow a hammer drill and buy a couple bits.

EDIT: price is 899 +50 shipping

-klb

[71sierragrande]

The main thing to consider isn't the cost of the unit, it's the efficiency. The operating cost (KWh's) will quickly surpass the cost of the unit if it is inefficient. I have had several portable, and window units and the operating cost has been 10-20x the purchase price. I dumped all that this year and rigged up an exhaust fan system which saves us $150-$200 a month. But I live in a moderate climate with cool nights.

[1972RedNeck]

We took a big truck radiator and coupled a big squirrel cage fan to it. We run well water through the radiator (55* or so) and just run the waste water out on the lawn. It will keep a 3200 sq ft shop cool in 100+ weather.