3 Car Garage Swamper or AC?

So living in the desert it gets a bit hot (like 109 today). My 3 garage is finished and stays about 10 degrees cooler than the outside temp.if I leave the doors down.

Currently I have small portable swamp cooler that makes it about 10 degrees cooler as long as it's blowing directly on you. It only covers the immediate work area.

AC would be great but I don't know of a way of installing one without using a contractor. (I dont do carpentry or eletrical) Don't know if there are portable units that would work.

As for swamp coolers; I saw one online that holds about 10 gallons of water and would appear to do the job. I'm looking for something that will lower the temp about 20 degrees. This would keep my garage about 80-85.

Note I'm in one of the driest deserts in the world so humidity isn't an issue.

From living at the other end of the state for a while - you're in prime territory for a swamp cooler because humidity is something that can mostly be treated as hearsay. OTOH you might need a pretty hefty swamp cooler for a three car garage, so looking into a ductless system (mini split?) might work better. 

Do you have a window in your shop? If so, you can get up to a 25K BTU window A/C, that's what I have and it def does the job!

You'll need a 240V outlet, but other than that it's pretty much plug and play.

I'm in desert too and did swaps as a side thing. They are very simple and effective. If you have a window you can install a cooler that doesn't take up shop space. I've picked up good window coolers off of Craig's for under $100. 

Tom1200 said:

AC would be great but I don't know of a way of installing one without using a contractor. (I dont do carpentry or eletrical) Don't know if there are portable units that would work.

You can get DIY mini-split units.  Here's one source, but there are many others: https://www.homedepot.com/b/Heating-Venting-Cooling-Mini-Split-Air-Conditioners-DIY-Mini-Splits/N-5yc1vZ1z18ggo  You would have to make electrical connections.

I am adding 1200ft on to the back of my house and it just happens to share a long wall with my garage. The additional area will be heated and cooled by a multi zone mini split system that will heat and cool the garage as well. It also gives me a reason to run heavier duty cable and 100a circuit with disconnects to the addition and garage because, well, power!

BoxheadTim said:

From living at the other end of the state for a while - you're in prime territory for a swamp cooler because humidity is something that can mostly be treated as hearsay. 

Wouldn't the swamp cooler raise the humidity within the garage very, very quickly? I could see one being useful for a quick solution but not something you'd leave running like an AC unit. 

I should add there are no windows in the garage.

I wouldn't use a swamp cooler in a garage.  I'd consider the added humidity unacceptable for cars, tools, etc. in the garage.  

cyow5 said:

BoxheadTim said:

From living at the other end of the state for a while - you're in prime territory for a swamp cooler because humidity is something that can mostly be treated as hearsay. 

Wouldn't the swamp cooler raise the humidity within the garage very, very quickly? I could see one being useful for a quick solution but not something you'd leave running like an AC unit. 

Swamp coolers do add humidity to the air it is part of the cooling process. In a dry climate, desert, additional humidity is wanted – to a point. In a properly set up house (or garage) the cooled air is allowed to exit via open windows. That exits the hot air and excess humidity. The only time a swamp cooler creates a humidity problem is when “monsoon” conditions are in the area. This is partly addressed by using only the “vent” setting which does not put water on the pads.

Tom1200 said:

I should add there are no windows in the garage.

You could add a window or an opening

DIY Mr Cool mini split is (probably) what you want. It comes precharged so as long as you're comfortable running the wiring and cutting a hole in your wall for the hoses, it really is a DIY system. Plenty of places will ship them to your door. Best thing I've ever added to my 3 car garage in the desert. I only turn it on when I'm going to be in the garage, and the garage is uninsulated and full of air leaks, but it still cools it down substantially. Heck, fourth of July we were sitting in the garage with the double door open, and I still had it on, blowing over us. Felt great even though it was probably close to 100 outside.

In reply to spedracer :

Also Mini Splits are available on Overstock.com under a few brands as well. Get the next size larger than you will need. Garage doors are inefficient and you will be chasing that loss forever with an "proper" unit

This thread is relevant to my interests, because my shop is large and hot this time of year. I've looked at swamp coolers, but I've always wondered how efficient an evaporative cooler is in Florida, where our typical humidity level in the summer is "broth." 

Of course, the flip side of that is cooling 3000 sq./ft with 16' ceilings seems fairly daunting from a power consumption perspective. I'm almost thinking my best bet is lots of fans and resigning myself to doing laundy more often in the summer.

In reply to Tom1200 :

If you have windows hang a A/C  in the window and plug it in the wall.  If that sounds scary get one of the "home Handymen" to do it for you.  
     If you really want it to work best put it up in the Gable end on the North side if you can.   That same home handyman will have to cut a hole in the wall for it. Then trim around it.  It'll probably double the install cost.  ($100 instead of 50)  keep the remote near the entrance so you can turn it on as soon as you open the door.   It will take a while to remove all the heat everything has, but once it achieves that  it will be like your air conditioned house is.   
    Swamp coolers need water run to them and will cause things in your garage to rust   

In reply to JG Pasterjak :

Even if you don't install enough cooling capacity to actually get the shop temperature down all that much, an A/C unit will still make it a lot more comfortable in there.  An undersized unit running flat out may only drop the temperature 5 degrees while you're working, but it'll pull a lot of moisture out of the air so you'll just be working in warm rather than warm and soupy.  

HALF truth: swamp coolers cause stuff (tools) to rust.

Reality: If stuff is rusting in a swamp cooled house or garage it is likely because the area is not vented properly for cooler usage.

Venting gives the warm air a place to go when the cooler air is blown into the building. The warm air takes the excess humidity out with it. Out with the bad (hot) air – in with the good (cool) air.

There are calculations (a.k.a. math) online that determine how much venting (usually open windows) is needed to properly vent an area. You can also use venting to direct the flow of cooled air.

When I was doing coolers as a side thing I would get 3 or 4 calls per season from people complaining about the humidity in their house. 100% of them did not have any windows open or sufficiently open. When I would call them back a few days later they were amazed how much better their coolers work.

The nice thing about a portable swamp cooler is that you can bring it to the track with you.  The downside is that they take up floor space.

I know several people who have roof mounted swamp coolers in their garages and the humidity isn't a problem.  One thing to keep in mind however is that it raises the air pressure in the shop and can push fumes into the house if it's an attached garage.

In my shop in NY I installed two window AC units.  One in a window and the other I mounted in a hole I framed in the wall.

The 25,000 sq ft Flyin' Miata warehouse is cooled by massive swamp coolers. We don't get any notable surface rust on parts that are sitting on the shelf or in the R&D area. We definitely have ventilation, though. You can't just turn them on and push air in. If I was doing a swamper on a garage, I'd definitely plan for through flow of the air.

I have a couple of window AC units cooling my 1200 sq ft shop because I don't have water there. It took more BTUs than expected - like double the calculations - to get on top of that building, but it gets a lot of solar gain. If I were doing it again, I'd be looking at heat pumps instead because then I wouldn't have had to run gas service to the shop. But that's done and in place, so there we are.

Now I'm wondering if just a ceiling fan would help here. It's a two-car garage with a pedestrian door at the back.