Portable Air conditioners..Your thoughts?

[Juicegoose]

Down here in Houston it's freakin HOT!!. Even though i've got a garage thats attached, insulated on all but one side, & has a orientation that keeps the sun at bay it's still hot. I was thinking of picking up one of those portable AC units from the lowes or home depot. I'll be cooling roughly 600 sq feet.

Any personal experience with them. Are they worth the investment. Yada yada you know the routine!!

Thanks guys.

[PaulMarcel]

The ones with a single tube to the outdoors are noticeably less efficient; you'll want two venting tubes (in and out). Window A/C units are even better as the whole condenser is outside. Maybe you have a window; would be perfect.

When I use mine, I make sure it blows straight down the area where I'm standing. Though it will take quite awhile to cool my garage, you don't really care when 45ºF air is blown directly on your area.

Someday I'll get a split unit with the condenser outside and the blower inside, but with the garage being in a 2-story house, the installation is complicated a bit besides not really having a good place for that condenser. Maybe I should put the condenser right out front and put a planter on top to hide it.

I'd recommend trying a small portable swamp cooler, but you're in Houston :-P I have one of those, too (shopvac size) and it works wonders with the right dew point.

[areynoldsre]

They are worth it but just watch out for how much power they pull. You might not want to plug it into the same circuit as you tools and you will notice it on the monthly electric bill. Being in Houston, I'd think it would be worth it (If I lived in Houston I'd help you install it). Where I live in Northern California it wouldn't be because we only get 5-6 super hot days a year - a fan is enough for most of our summer.

I have helped a few friends install window AC units and that always works to cool one room. 600 sq ft. shouldn't be too hard but check the ratings on what ever you get.

[mpatrick]

I've got a window unit in my garage here in houston. Its only one car but is insulated much like yours. All I can recommend is buy one that is rated for close to double the sq ft that you have. It takes a lot to overcome the initial heat, when you first start it up. I have a 8000 btu and its still in the mid 80's with it running full blast. I think I am gonna get a bigger one here pretty soon, if my truck will stop breaking down.

[mpatrick]

also there's a guy on lumberjocks that's in leauge city that has a 14000 btu portable unit and says it works great in his 2- car garage.

[Vic]

Be careful how big you you size the unit, especially in a humid environment. If it's too big it will short cycle and stop prior to removing the humidity, leaving the space cold and clammy. The most efficient are the ductless mini-splits Paul-Marcel mentioned. Because they have variable frequency drive on the compressors they do a great and energy efficient job and can be oversized without the short cycling penalty. Both the indoor and outdoors units are quiet and do a much better job of supplying an even tempered environment.

[carverken]

I have one in my 575 sqft shop. It vents through a drier vent. It does OK. Its not cold but it draws the humidity out and cools it down a bit. Just my two Lincolns. K

[sbarton22]

Honestly, I had one in a studio and the power it used was immense, and it was a brand new high efficiency deal.

The proper solution is expensive, and I know this because I have the same issue staring at me in the face.

1) get some insulation in that wall. You are just throwing good money after bad.

2) look at a spit system unit. Like This It is ductless and the condensing unit is very small.

This is an extremely high efficiency solution. If you are looking to stay cool there for just one summer, don't bother. If you are looking at 5 years, this sucker should pay itself off in a hurry.

Trust me, I understand it is an expensive solution. I have been putting it off and is still the reason I work out of my basement and not my garage.

[DeGauss]

I use one in my shop here in Kansas City (Hot & Humid)and it works great for the space. I cut a hole in the wall and installed a clothes dryer sleeve and vent out through that. This is it's third year and still going strong.

-Gary

[jHop]

I've heard of people using window units by cutting a hole in the wall, but I don't think this is recommended. I'd look at the room sizes versus the BTU settings, and you'd factor in the height of the room, too. (All of this you probably know already.)

I'd consider, regardless of which system you pick, that you get a timer for the AC or dehumidifier unit. Or maybe a dedicated switch, or timer switch. (I think it ironic that I had to clean out an industrial facility that flooded to see my first timer switch, and then I couldn't stop seeing them.)

[Texfire]

I'm in Austin, and I considered a portable, a window unit, and a PTAC. Ultimately I've decided to go with a mini split for the reasons above. I don't want to spend lots of money and still end up hot. Too limited in good shop time in Texas without an AC.

[jonny transcend]

Im in the same boat. I almost passed out today from the heat! My fan was my only salvation and it broke! Im in corpus christi texas so its humid and hot.

[Juicegoose]

Thanks for the wise words guys. I've thought deeply about the mini split as well. I'll have to look into it more.

Dang it's hot though.

[dmorrison]

I live in the DFW area and though were not as humid as Houston, It does get hot and humid with the southerly flow during the summer.

I have a 3 car garage. 1 bay is my shop and it is open to the other 2 bays. Above the garage is a 500 Square Foot finished room. The AC/Heat setup is not the best. So I tried a portable unit form Costco rated at 12,000 BTU for the finished room over the garage.

Since we don't go up their during the day much. We would leave it off until an hour before we would go up their. With the heat build up, the unit could not keep up. It would take 2-3 hours to become comfortable. It was a double hose unit that was putting out cold air. It just could not overcome the heat buildup during the day.

Now my garage has a 18,500BTU window unit that I had in my 2 car garage in our last house (wood doors 2 walls with no insulation and facing south). Now, I turn my AC on about 20 minutes before I go into the garage( 3 car, 1 wall insulated, Garage door insulated and 3/4 of the ceiling insulated). By that time the garage is comfortable, Not cool, But the heat has definitely been cut. This last winter I insulated the metal garage doors with a kit from Lowes. WEll worth the effort and time. The garage side walls are not insulated and 3/4ths of the ceiling is insulated.

After being in there an hour it's quite comfortable. The AC does not cycle. It's Texas and it's hot. But I'm happy with the setup.

My recommendations. 18,000 to 20,000BTU for a 2 car garage. 24,000 for a 3 car garage. Of course insulating does help reduce those numbers. The garage door insulation kit form Lowes is fantastic. Item # 222457

I would only recommend the portable AC if you can get it at a place that has a good return policy like Costco. I tried it for 2 months and realized it was not going to work so I returned it. Second. How much time do you spend in the shop. I'm not out their 8 hours a day. So I want the Ac to be able to cool it down quickly.

Over capacity was mentioned by someone. In the summer in Texas I would not worry about that. My 18,500 runs continuously trying to cut the heat during the summer. It's just so dam hot hear in the summer.

Window or in the wall. My last garage was in the wall, no windows. This garage, it is in the window. When we sold the last house I had to repair the hole ( had extra bricks ). So take that into consideration.

Dave

[NotAShakerMaker]

I have a friend in Houston with a garage workshop who just had an HVAC guy extend a run from his primary HVAC unit into the garage. The extension is designed to be removed when he sells the house, as the dumping of HVAC into a garage without a return is definitely a no-no. However, it seems to work. He super insulated the garage doors and put heavy commercial plastic warehouse drapes that he can close off the garage door end of the garage. He claims that having just a few inches of dead air between the doors and the curtain really helps insulate that end of the garage.

He doesn't have a bonus room above his garage, but bedrooms. He claims that the ceiling was insulated the same as the rest of the house, so he loses or gains little heat through that path.

I find the workshop to be a bit too warm for my taste, but since I'm not paying the electric bill, my vote doesn't count.

[tim0625]

Down here in Houston it's freakin HOT!!. Even though i've got a garage thats attached, insulated on all but one side, & has a orientation that keeps the sun at bay it's still hot. I was thinking of picking up one of those portable AC units from the lowes or home depot. I'll be cooling roughly 600 sq feet.

Any personal experience with them. Are they worth the investment. Yada yada you know the routine!!

Thanks guys.

Ok guys....I'm thinking out of the box so I don't have to knock a hole in the wall of the cinder block and brick in my 2 car detached garage shop to put a window unit. One of my customers is giving me an 2 ton heat pump that has a bad compressor. What I'm going to do is gut it and then circulate cool water from the house through the air conditioner's coil instead of freon and use the top fan on the unit to pull air through the coil and cool the shop. The water that's circulated through the unit and discarded will be hooked to the sprinkler system to water the grass and garden. If I ever move, just detach the unit from the water system.

Different I know, but what do you think?

[Beechwood Chip]

I've always heard that you want to water plants just before sunrise. If you water at night then you get slugs, mold and other things that like damp, and if you water in the day then a lot of the water just evaporates and doesn't get to the roots. Also, you want to give the plants a good soaking once or twice a week, rather than giving them a little water each day. That way they grow deep roots, as they seek out the water that has soaked deep into the ground.

If you could save the "discarded" water to use at a different time, you wouldn't need to water the plants according to your woodworking schedule.

Can you dig a ditch, maybe on the shady side of the garage? Maybe if you circulate the water through some pipes in the ground, it will come back cool.

[BenMinshall]

What I'm going to do is gut it and then circulate cool water from the house through the air conditioner's coil instead of freon and use the top fan on the unit to pull air through the coil and cool the shop.

Unfortunately that method will not be effective at all. The reason freon works is because it undergoes a gas-liquid-gas phase change as it is evaporated, compressed and condensed while circulating through the AC system. Without the phase change the amount of energy (heat) the system can move is dramatically reduced probably to the point it will not produce any noticeable cooling effect. You would need a heat exchanger with much greater surface area than an AC coil to get a cooling effect from liquid water.

Water cooling is only effective if it can be evaporated (phase change) such as in a swamp cooler in a low humidity outdoor environment or if it is chilled to a much lower temp than room temperature using conventional refrigeration equipment.

[MaidensGator]

Sorry, but I have to agree with Ben that it won't work. It may seem like semantics, but a typical air conditioner does not make the air cool, it removes the heat. The freon does this through evaporation, then is compressed to be evaporated again. The fan on the unit is blowing the heat off the coils. I have a very old water cooled system in my house that uses water instead of air to cool the coils. It is very efficient because the water running over the coils draws off a lot more heat than a fan blowing on them would. These systems were popular in the 80's before anybody worried about wasting the ground water. I don't think you can even put them in anymore. My AC is water cooled, but what's being cooled are the coils, NOT the air.

[DadoHead]

I just installed a Klimaire mini ductless split system heat pump in my sun room in Florida. I installed it myself, all you need is to cut a 2.5 inch diameter hole in the wall to route the refrigerant, condensation drain and low voltage line. The connections are flare fittings, the units come precharged with R410. The 3/4 ton unit was $650 off amazon and it cools better than my 3 Ton Goodman for the rest of the house! I want to put a 2 Ton system in the garage now. My wife might never see me again though...

[Southwood]

Dadohead, thanks for that. I didn't know there were DIY kits out there. Might come in handy, next summer. This one is too far gone now.