Ductless split unit recommendations?

[matemike]

I want to be able to cool off my 30x40x12 insulated shop. Southeast Texas area; 100°+ days with 90% humidity are common. Is there a ductless split unit that can achieve this?

I hear that during the summer, the fact that my shop will be built with 3" roll-in insulation it will be 20° cooler than outside. Hoping this is true and being the reason I went with insulation, 80° is much better than 100°, but it is still a bit warm to be working on/under vehicles and hope I can make the shop cooler.

I hear guys without insulation can drop the temp 20° by opening all doors and have some fans going. Since mine will be insulated, would opening doors and using fans hurt me or help me lower the temps even more?

Or back to my beginning question; could I just install a ductless split unit and call it good? Leave the doors closed and run A/C for 30 minutes before I start working. If I got it down to 74° in there it would be a huge plus. But would that require a humongous split unit, or would one for 1200 sq ft be good enough figuring that's probably the rating for an 8' ceiling?

 

[theoldwizard1]

I want to be able to cool off my 30x40x12 insulated shop. Southeast Texas area; 100°+ days with 90% humidity are common. Is there a ductless split unit that can achieve this?

Good insulation is key ! For a building that size you are going to need 2 inside air handlers at opposite ends of the building and an appropriate sized outside unit to handle temps over 100°.

Mitsubishi is top of the line.

 

[jonjon1]

I would have a heat loss/gain calc. done, and I would go with a package unit over mini splits ALL DAY....

Even 2 of these units would cost less than a mini split...
http://www.amazon.com/dp/B006X1B1EY/?tag=atomicindus08-20


Very easy install, just pup a hole for the duct work supply and return, and run your electrical to it {thermostat and service}. I have installed them in 2 hours, start to finish... They come precharged { I normally check them but out of hundreds of 410a rooftop and ground mounts not one was off enough to change the charge}...

You can also get them with heat pumps built in for the cold Texas winters
http://www.amazon.com/dp/B00E8FYVLW/?tag=atomicindus08-20

You can obviously buy these units local to you at a supply house for less, and since 410a is not controlled, there shouldnt be much to do about purchasing it with out a license, also its a sealed package unit like a window a/c, so should be easy to find...


Either way you go sizing is going to be KEY, off the top of my head, knowing nothing about your buildings insulation or texas except the few times I have been there hunting hogs, I am going to say you are going to be in the market for a pair of 3-3.5 ton units {minimum a pair of 2+'s}

 

[cagullett1]

Here's a good thread on an install last year. I followed it and plan to install one soon.

http://www.garagejournal.com/forum/showthread.php?t=247895&page=7

 

[Rockhead261]

Mini splits do not fare well in industrial environments. The blower wheels and coils load up quite easily and they're a real PITA to disassemble and clean. I'd strongly recommend a conventional split system if you're planning on doing anything more than typical homeowner hobby stuff.