A/C for a 2 car garage/shop

[CarvedTones]

This time of year I get almost nothing done because of the heat. It's been compounded this year by having a lot of stuff in the garage, but it is down to tight, but manageable now. I am thinking about the possible options for cooling. I do hve a window, but I am in a Cary neighborhood and a standard window unit is not an option. It is on the side of the house and somewhat obscured, so I could use it for something temporary, like a vent for a portable A/C, which seems like the best option for a couple of reasons, that being one. The other is that thinking throughhow I would use it, I would often not really have time to cool the whole thing before I started working, so rolling a portable to the area where I am working and having it blow toward me would probably work best. Budget is the usual - as little as possible. Thoughts? Experiences? Units to look at or avoid?

 

[Tarhead]

Andy,
I did this last summer and it allows me to be able to work when it's 95 outside.
Discussion here:
http://www.ncwoodworker.net/forums/showthread.php?t=8868

 

[Don Sorensen]

Wow, Mark, that was a great write-up. I've got a little window unit in my two car shop and it doesn't do much but make noise - and bruises on my arm when I mow the yard.

Andy, saw that Northern Tool has the 24 inch high volume fans on sale. Like some of the other had said, the fans help a bunch. If I wasn't between jobs right now, I'd have bought one of those 24 inch fans yesterday.

 

[jlwest]

If your HOA bans window AC units put in a through the wall unit. They can be put betweem studs (vertical) to simplify installation. I would also recommend insulating the garage door.

Jeff

 

[CarvedTones]

Andy,
I did this last summer and it allows me to be able to work when it's 95 outside.
Discussion here:
http://www.ncwoodworker.net/forums/showthread.php?t=8868

Interesting - I just stopped at BJ's this morning hoping to order new glasses, but the optical shop doesn't open until 10:00. So I wandered over to the A/C units and that Amana does seem like the value leader. It's $319, so with tax I guess it is about the same as what you paid. I am thinking about a window adapter; one of the other models comes with one, but it was a brand I wasn't familiar with (Haier? something like that). Their units were more than the Amana except the 10,000 is on sale for $315. It seems like the Amana is the batter deal though if it doesn't include anything for the venting it's hard to say.

A few reasons for wanting the window vent - we were talking about selling before too long. The economy has made that a bit iffy. We have had one of out central units go out a couple of times and being able to roll it in, pop the vent in a window and cool a room or two would help a lot with the justification.

Do you know what the max length of the vent hoses is?

Jeff (jlwest),

I am pretty sure my HOA frowns on anything but central though temporary seems to be okay. If I did get a complaint about window venting a portable (highly unlikely unless I left it there for weeks at time), then I could just do what Tarhead did.

Yeah, I need to insulate the doors. All the walls are insulated. I was thinking about just cutting squares from the thin foam to fit in the panels.

Don,

You are frowning on plan B - they have a small window unit for about $100. It is so small it needs no outside support so I could put it in to use it and take it out when done. I lifted one up from the shelf to make sure it was light enough. I would have to work right in front of it though; no way would it cool the whole garage. And there is a reasonable likelhood of getting a complaint even for temporary use.

I have a few "regular" fans, but even those are a pain. I do a lot with plans out (yeah, I can get a plexi holder) and I do a lot of rotary carving use this type of dust collection:

(I bet you thought I was older than 8 :gar-Bi)
That actually works quite well, but it doesn't take much airflow to send the dust elsewhere.

I think I am going to push for the Amana.

 

[Tarhead]

Andy,
Mine came with a window vent insert. The hoses stretch out at least 5 ft. Make sure to consider the dual hose models. They're more efficient.

 

[CarvedTones]

Andy,
Mine came with a window vent insert. The hoses stretch out at least 5 ft. Make sure to consider the dual hose models. They're more efficient.

I may have been confused about which box I was looking at or maybe they both have the vent kit included, but from looking at your pictures I am pretty sure I was looking at the same unit (or maybe this year's equivalent if they have changed the line any). Yes, two ducts. I don't understand how just one duct could work unless it was a very short duct and the unit could "breathe" in and out somehow. My understanding from talking to A/C techs in the past is that air ducts can be fairly long without much effect if they are properly sized and unobstructed because it is about moving air, not pressurizing it.

 

[junquecol]

Why not build a box on the inside of the garage and mount unit in it. Leave screen on outside. Actually remove window sashes and rehang on box. Spray paint inside of box, and outside of unit black. Looks like a dark hole from outside. Don't brag to neighbors.

 

[CarvedTones]

I had a thought along those lines. I thnk it would overheat.

 

[CarvedTones]

A 9000 BTU in "excellent" condition just popped up on CL in Wilson and I will be driving out 264 in the morning. I emailed the seller to see if it would be possible to meet up. Assuming I get a postive answer (seems like a good price, so it won't surprise me if it is gone), is 9000 BTUs enough? I have a fairly standard 2 car garage.

 

[JimmyC]

Andy,

If your garage is insulated, including the ceiling and doors, 9,000 btu's should be more than enough. Either way, it will make it much more comfortable in there than it is now.

Good Luck,

Jimmy:mrgreen:

 

[CarvedTones]

OK. I called and he can meet me and is willing to hold it. He's right off 264, so I will be able to swing through and see it running and feel the air.

Way cool I hope!

EDIT - Just noticed this other thread:

http://www.ncwoodworker.net/forums/showthread.php?t=15711

Now I am not worrried at all about capacity.

 

[junquecol]

Andy, remember that my shop is built like an ice chest. 1" of styrofoam sheathing on three walls, R-30 and R-19 in ceiling, insulated roll up doors, and located IN THE SHADE. The latter probably makes the most difference. As for unit overheating, surround the discharge air and send it out the window.

 

[CarvedTones]

OK. I called and he can meet me and is willing to hold it. He's right off 264, so I will be able to swing through and see it running and feel the air.

Way cool I hope!

EDIT - Just noticed this other thread:

http://www.ncwoodworker.net/forums/showthread.php?t=15711

Now I am not worrried at all about capacity.

Well, I bought it. It's a Haier 9000 BTU. It is one that I recieved a suggestion not to get due to efficiency - single hose - and I would not have gotten one new, but the price seemed reasonable for used. I think I can list it and get what I paid ($150) if I decide it won't work for me. The seller had an HVAC type air temp thermometer and did demonstrate that it was getting about a 15 degree drop. I mentioned the single vent issue to the seller and he agreed it probably would be more efficient but he was cooling a good sized space with it and had no problem. If it does work out for me and I decide to add a wall vent, just adding one hole through the wall is a more attractive option. I did some Googling and there are definitely mixed reports. I will have to be very careful about making sure filters are kept clean.

I will need some better testing than my initial test (yesterday afternoon) to be sure I will be happy with it. I had the garage door open in the afternoon and closed it before the rain came, purposefully locking in air that was near 90. I turned it on and with a couple of minutes that corner of the garage was acceptably cool. I put a standing fan near by on low pointing toward my bench and that made it acceptable right away. I started the fan cycling back and forth distributing it across the entire garage and it was about a half hour before most of the garage was cool but I would have been able to work in the half away from the big doors (which is where I have everything) pretty much right away. The big doors are not insulated and have obvious gaps (I see a stripe of sunlight on the wall in the afternoon)

One thing I did find Googling around is that people often use drier vent extensions to move the units further from the wall than the supplied duct allows. That could make it substantially more useful. My garage/shop is still a garage - the big doors get opened a lot. Coming in to a hot garage and wanting to turn it on and start doing something immediately will be common.

Anyway, it will be a few days before this is a full on gloat. I am optimistic, but until it is actual use I won't gloat

 

[JimmyC]

Andy,

You're going to kick yourself in the butt for not having done it sooner. It may not work all of the time (100 degree weather:dontknow but it will make you comfortable much more than if didn't have it . The dehumidifying is worth the price alone.

Jimmy:mrgreen:

 

[CarvedTones]

Andy,

You're going to kick yourself in the butt for not having done it sooner. It may not work all of the time (100 degree weather:dontknow but it will make you comfortable much more than if didn't have it . The dehumidifying is worth the price alone.

Jimmy:mrgreen:

Those bad days are the quandary - I think a 12000 BTU double ducted unit would work then and I will probably have to use this one like a "space cooler" under those conditions, blowing air from the unit directly toward me. But I am not sure even the 12000 would work because of my doors (not insulated and leaking air). But when I closed the doors yesterday it would have been brutal to work out there and within minutes it was fine, so I think I will be happy with this in nearly all conditions. Do the exceptions warrant the extra cost of a new unit? :dontknow: Probably not, though I might have a different opinion on a really hot day.

 

[Tarhead]

Andy,

Congrats on the cool tool and great deal!

Get some pipe insulation and wrap the exhaust...especially if you extend it with dryer vent hose. My exhaust puts out quite a lot of heat and you don't want that radiating back into the shop.

How does your system deal with condensate?

 

[CarvedTones]

Andy,

Congrats on the cool tool and great deal!

Get some pipe insulation and wrap the exhaust...especially if you extend it with dryer vent hose. My exhaust puts out quite a lot of heat and you don't want that radiating back into the shop.

How does your system deal with condensate?

That may be one redeeming value of single hose - condensate is all evaporated into the exhaust. Do the dual ducted models do that? I am guessing it would be more difficult if that airflow is completely separate. But in some comments I read, that is an issue if you have a "too well sealed" area cooled with a single ducted one; it will reduce the exhaust airflow so much that it can't evaporate fast enough. But I am reading between the lines a lot.

I may be too trusting, but I really got "good vibes" from the seller. I believe he really was happy with it. He was selling both this unit and a window A/C at the same time so his story about getting central stands up to scrutiny. He told me I could try it and bring it back if it didn't work for me (yeah, he knows I am not close by but I still think he was honest).

That duct is hot and that would be an issue if I extend it. I am not sure I will. I had another thought occur to me that might be a terrible idea or might work out okay - would you consider venting one into a crawlspace? If I did that, I would use one of the type that aimed the airfolw down so it would mix with air in the crawlspace and not just heat the floor right where it came in. If I did that, I could place the unit on the house side of the garage right next to my bench.
EDIT - some additional info on the crawlspace idea...
It is never hot under the house.
I could put an extension in the crawlspace; there is a vent to the outside about 8' from where I could add the vent hole.
The A/C will only occassionally be run for more than 4 hours at a time.

 

[Tarhead]

Andy,
Mine pumps the condensate over the condenser and evaporates all but a few drops. I have a 1/4" tygon tubing run out the door and have only seen small drops of water in there.
Venting into a crawlspace would not be a good idea in my opinion. Hot, moist air would cause lots of problems. Pulling cool air out of your crawlspace and into your shop is a good idea...especially for make-up air from the single tube exhaust. PeteM has an opening in his shop to his crawlspace and with a fan and it was comfortable on a very hot day when we had the CLT shopcrawl...kind of like a geothermal heatpump.

 

[CarvedTones]

Pulling cool air out of your crawlspace and into your shop is a good idea...especially for make-up air from the single tube exhaust.

I like this idea a lot. :icon_thum
If I do that and try to get the big doors to seal a little better I think it might handle even the hottest days.