Getting ready for the 'Bot & air conditioning?

[dubliner]

Hey all, I'm in Austin Texas and the shop is not very comfortable during the summer so I was contemplating ( trying to decide which one ) AC for the shop. I was looking at those "split systems" as I dont want a big closet & ductwork in the shop. I did find a 3 ton unit that is one condenser & three fans which would be ideal in my situation. I have an office "upstairs a handtool/finish room below that & the rest is open. Walls are SIP foam and I have made insulated doors that do a decent job - so generally a tight building - any advice would be great thanks Neville

[Brady Watson]

Neville,
How many square feet is your shop? I use a 23,000 BTU window unit that sits in the cinder block that really cools the shop down. It gets so cool in fact that you'll get the 'bends' if you come into the shop after being out in the heat too long!

One thing that really helps to keep the shop warm in the winter & cool in the summer is Reflectix. Google it. You can find a similar & cheaper product via FarmTek.

-B

[bleeth]

To protect your AC make sure you have a tight filter system for returned air. The size of the unit required will be effected by the cubic feet of the space. I ran 3 tons for a 1000 square feet and it did a great job.

[elcruisr]

Yup, 10 tons of air on 4800 SF of wood shop w/ 18 foot ceilings here! Six years and running. Use only the best filters and learn how to use non acid coil cleaner!!!!

Remember that a large vacuum hold down system can also produce a lot of heat. On the hottest days with the 'bot crankin we can only hold mid to upper 80's but that sure beats what's outside! If you're running a spindle in high summer heat you can push hard enough to overheat it if you try. Some days we can still be borderline on the temps as it is.

[chodges]

Do you have any attic space in your shop?

A friend of mine put a central unit above his shop, with the "return" vent in the center of his ceiling, and the "supply" vents near the walls.

This works really well, as it seems there is a little less dust to get into his filters at ceiling level.

[dubliner]

Hey guys, I have about 1600 sf, but the walls & roof are 4 1/2" styrofoam & OSB ( SIPS) so I guess the Reflectix is out. I noticed about a 25 dg difference between outside wall Stucco & inside(placing hand on wall )
As for the return air, how does that work in a ductless split system? The unit I was looking at had three fan units & one outside unit - 3 tons ( 24000 btu I believe)
No attic, just open space.

[harryball]

I'm running a split HVAC heat pump system but have attic space and installed duct work. On a ductless system there should be a return opening that will suck the air in. That will need a VERY GOOD filter over it. I built 2 custom filter boxes and installed 2) 16x9x2 pleated filters on each. They are rated for data room use. I forget the smallest particle size but I've checked the coils and they remain clean. We have R15 walls and R30 ceiling with attic space and the system does very well.

I generally set it and leave it on 79 degrees. Believe it or not that's comfortable because it's pulling all the humidity down. Mine is a full heat pump so it heats in the winter. I leave the heat on 60 degrees and let the tools do the rest.

On your system, I would recommend that you either duct the return to the other end of the building or the output. I've run cooling units in data centers and we always found unless we ducted the output under the floor or through ducts we'd end up with a very cold area right around the unit while everything else was warm.

Robert

[Brady Watson]

Neville,
Mine works pretty well, but I have a partition wall down the center. I'm right about 1600 Sq ft downstairs, with another 1000 Sq ft upstairs. It does a good job, but I've found that a circulation fan to keep the air moving around the shop is needed if you have a ductless system like a window unit etc. If you leave it running for a full day, you can hang meat in there!


-B

[harryball]

LOL... that reminds me of the time we went away for the weekend and somehow the AC was set to 60 degree instead of 80 degrees in the shop for summer service. I believe somebody mistook summer for winter and AC for heat. Anyway... it was ready to slaughter hogs when we got back. I wondered when we drove up what all the water was doing running down the windows of the garage doors!

To the AC's credit it was about 95 degrees outside and inside it was 65 degrees. Not bad for a heat pump to pull down 30 degree. I was expecting the worst on the power bill, but it was only about $20 higher than what I expected.

Robert

[dubliner]

I've found two price ranges from 3K to 5k for 3 zone unit. High price is a Freidrich unit, lower one link below, any AC guys have an opinion on this lower cost unit? TIA - looks like I'll have to buy a panel cart as well :-), all these additional cost you guys never mentioned to me...
http://acforsale.com/online/product_info.php?cPath=36_123&products_id=2448

[gabriel_mckeagney]

all these additional cost you guys never mentioned to me...

Oh, and by the way Neville, there is also the LEARNING CURVE$$$$$$$$$$$$$$$$$$

Gabriel