Mini split ductless AC

[Mike Heidrick]

Anyone install this type of AC system in their shop? I have started looking into an air conditioning system for my shop and I do not have HVAC duct work installed (although I do have a ton of spiral sitting on the porch - hmm). I have a gas furnace for heat that hangs from the ceiling and blows hot air into the room. Not sure what my best solution is for AC. I plan to call a HVAC guy for advice (Duane got any ideas??). Just throwing out a request for info to the members here.

[Joe Jensen]

Mike there have been a few threads here this summer on AC in the shop. I put a 24,400 BTU mini split heat pump in my garage in May. I have a well insulated attic, and I put 1.5" of ureathane foam on 3/4 of the garage doors. The walls are uninsulated. I have to say that I'm not completely satisfied. If I start the unit in the heat of the day, (110F) in Phx, it can only cool the garage down to maybe 85 in a couple of hours. If I start in the morning, I can get it to stay below 82 during the heat of the day. I am going to have the tech who installed it come out to make sure it hasn't lost any charge. It may be a limit of this type of system. One of the specs is a max outdoor temp. The Sanyo system I bought had the highest rating, and that was 115F. The installer said they will slow down when the heat oustode is too high, I think that's what's happeneing with mine. My outdoor unit sits on the west side of the house and I'm sure the temp of the case is over 130 in the afternoon when the sun hits it. Car surfaces are 150 here. I may also try a shade to the unit, and I may have the sidewalls filled with expanding foam.

Otherwise it's a great unit, very quiet, and easy to install. In Mn I doubt you have the high temps we see here. Also, my unit is 18 SEER, and with a clamp on ammeter it only draws 12.3A at 230V. We pay $0.109 per kWh here so running full bore for 12 hours would cost me only $3.50. Not bad considering that most of the time it runs much slower and I only run it on the weekends.

[Jim Becker]

I have not done this but will be considering it as a future upgrade from the window unit I use now. That's not really adequate for my shop size and there are no other windows usable for this purpose. Mini-splits are pretty nice systems and while they still require professional assistance to charge them, they are also pretty economical.

[Ward Probst]

I think you would get much better performance if you went ahead and insulated the walls and the rest of the doors. We have similar heat here and that's what I ended up doing.
WP

[Bob Slater]

I put a Fujitsu Mini split in the shop last month. I am very pleased with it.It has two output units for the two main rooms of my shop, so I can shut one down depending on use. It is silent, and makes the shop so comfy. The biggest improvement is how much less humid it is. It has a heat pump, so will heat the place up till about Jan/Feb (Toronto). I will turn it off when making a lot of dust, and start it back up when my overhead filters have cleaned the air.

[Joe Jensen]

I think you would get much better performance if you went ahead and insulated the walls and the rest of the doors. We have similar heat here and that's what I ended up doing.
WP

My doors have four panels, the three lower sections are solid and the top sections have windows. I really can't do much with the top sections. I do plan to have the walls insulated, as it's just the two sidewalls.

[Joe Jensen]

I put a Fujitsu Mini split in the shop last month. I am very pleased with it.It has two output units for the two main rooms of my shop, so I can shut one down depending on use. It is silent, and makes the shop so comfy. The biggest improvement is how much less humid it is. It has a heat pump, so will heat the place up till about Jan/Feb (Toronto). I will turn it off when making a lot of dust, and start it back up when my overhead filters have cleaned the air.

Bob, I boxed my blower unit in and added furnace filters in front so I can run all the time. It was a quick project. If you want a pic, let me know and I'll take one tonight...joe

[Bob Slater]

Bob, I boxed my blower unit in and added furnace filters in front so I can run all the time. It was a quick project. If you want a pic, let me know and I'll take one tonight...joe
Sure always love to see some PIX of a shop. Sounds like a good idea.

Bob.

[Eduard Nemirovsky]

Doing research for AC/Heat for my shed - ww shop. It is 20 by 24, will be a good insulation with spray foam.
Mike, did you install a ductless mini split unit? If yes, what is your opinion on this system? Which make did you install?

[Richard Link]

I recently installed a ductless mini-split heat pump unit into my 18 x 17 foot garage shop. Very simple one day installation and fairly inexpensive. So far, I've been very happy with it. I'm in Houston and the outside temp is certainly in the mid to high 90s and I imagine the unit is also hotter than that. Haven't insulated the garage doors yet (coming up) but did blow insulation into the walls. Very comfortable currently and a world of difference from the steam room environment I used to work in. So far I'm very happy. Haven't seen the first electric bill, though...

Rick

[Joe Hathcoat]

I recently installed a ductless mini-split heat pump unit into my 18 x 17 foot garage shop. Very simple one day installation and fairly inexpensive. So far, I've been very happy with it. I'm in Houston and the outside temp is certainly in the mid to high 90s and I imagine the unit is also hotter than that. Haven't insulated the garage doors yet (coming up) but did blow insulation into the walls. Very comfortable currently and a world of difference from the steam room environment I used to work in. So far I'm very happy. Haven't seen the first electric bill, though...

Rick

Rick,

Just post a question to this subject. Mind if ask who you had install it, what size, and the cost? I had a couple quote for my garage at 4k. Seem really high to me.

Thanks,

Joe

[Kevin L. Pauba]

I would check out acwholesalers dot com or alpinehomeair dot com. They have a selection of mini splits that you can buy direct.

Earlier this summer I installed a heat pump and high-efficiency furnace myself and found a contractor to sweat the fittings and do the little sheetmetal work that was required. Came in at < $3K (with the honeywell thermostat and cartridge filter). I'll be doing my attic soon and thought of using mini-split but, for me, the all-electric hybrid (heat pump & electric furnace) will work our a little better.

[alex grams]

I put a window unit in an enclosure similar to the setup on this thread:

http://www.sawmillcreek.org/showthread.php?t=91575&highlight=drain

Unit is 18,5000btu (1.5tons) and can cool the garage on a moderatly hot day from 90-95 to about 80 in 30-40 minutes. Like others have observed, the change in humidity is one of the biggest factors. I live in Houston, and it gets HUMID.

Garage is 75% insulated in the attic, no insulation in north and south walls, and garage door faces west with reflectix radiant barrier and 3/4" foam padding on the door. The temp gauge says it sits between 80-85 degrees, but feels MUCH better than that, especially with the humidity drop.

[Robert Parrish]

I had a Mr Slim system installed last year in my 900 sq. foot garage shop and I keep it between 78-80 with no problem. I insulated the doors and attic.