Arizona A/C Recommendation

[Jerry Booher]

It is 100 degrees and going up! My woodshop is 29x29. 2 block walls, common wall with house and garage-door wall which is insulated. Flat roof. Passage door on block wall.

What can I do to cool this? HOA (non functioning) CCNRs say no roof mount. Cutting through the block wall is not too appealing.

Is there some type of A/C that can sit in the passage doorway? Is it too expensive to run it with an open door? What voltage?

Is there some other solution? Speedo and a fan :)?

I am reluctant to use evaporative cooling since some of my tools have light rust due to high humidity during one of our infrequent rains.

Have I asked a question that has an answer?

Jerry

[Barry Richardson]

I've worked in a large woodworking shop that is cooled with evap for the last 3 years. No evidence of rust whatsoever. I don't think you have to worry about that. I think evap is your best, and cheapest solution.

[Nancy Laird]

We have a swamp cooler on our wood shop also, and we have absolutely no problems with rust. We have a Unisaw that has never seen a speck of run--since we bought it in 1993!!

[Dylan Smith]

It's easy enough to mount a side-draft cooler on a cart, and move it into a doorway, etc. Just make sure you've got cross-ventilation. It won't help you during the monsoon too much, of course...

[James Hart]

Jerry,

I tried the portable AC unit from HD. Vented it through the door. Did squat.

Tried the largest evap unit I could fine. Did OK until monsoon and/or 110 plus. The it did zip.

Just did a lot of insulation, which is key no matter what. You need to retain the cooled air so the unit is cooling it over and over. If the garage reaches 120 (mine was hitting 130), the best the AC unit can output on the first pass is somewhere around 98. The insulation allows it to cool the same air again, getting it down to a more comfortable range.

I went a bit overboard and installed a 2 ton unit outside. Small 1 1/2" hole through the garage wall to connect the air handler. It barely has to run to keep things at 80, even when it's 110. There's nothing for the HOA to see.

Jim

[Joe Jensen]

Jerry,
I just installed a 2 ton mini-split heat pump in my 3 car garage in Tempe. I haven't really run it much yet, but it's an 18 SEER unit that should be reasonably efficient. In max cool mode it draws 12.3A @ 220V per an amp meter clamped on. This one required a 3" hole through the wall. I considered a swamp cooler, but I hate the humid feeling, and I assumed that the wood would move too much with the humidity changes. I don't have insulated walls, but the ceiling is well insulated. Total cost for my system was around $2500 installed.

With concrete block walls, and likely no insulation, the walls will act as a thermal mass, taking longer to cool down, and then take longer to heat back up. I also assume the ceiling is uninsulated. A swamp cooler will be by far the cheapest, but you will still have the lack of insulation problem. How much are you prepared to invest in time and money? I insulated my garage doors and that helped a ton before I added the AC.

joe

[Jim Becker]

One suggestion would be a "mini split" system. They are reasonable in cost, easy to install and somewhat efficient.

[Joe Jensen]

One suggestion would be a "mini split" system. They are reasonable in cost, easy to install and somewhat efficient.

Jim, my mini-split is amazing. Where you are you don't likely have too many cooling days, but here in AZ it's awesome. Based on some initial usage, I think I can keep it cool from 7am-9pm on a Sat for less than $2 in electric :D

[Jerry Booher]

Thanks for the suggestions, guys. I knew I could count on you for some good ideas.

Jerry