2000 sqft shop A/C advice - mini split?

[bugman-74]

The flammable materials part would concern me

The solvent I use is similar to Safety Kleen. It is in a dedicated parts washing cabinet with a cover that has a fusible link. Spray paints and whatnot are stored in a flam cabinet.

The majority of my work in the shop is "wrenching" and not focused on flammable materials.

Code does require the furnace to be elevated from floor.

[shavedneon]

Hello fellow Tucsonian, I’ve built and conditioned over 20 garage-mahal types all over the area. A mini split will not make you happy or comfortable. Ducted unitary systems are much better. I have had the best results with 2 stage or inverter systems for shops. The problems are exaggerated in a shop, opening a door in the summer would overwhelm a mini. My current garage is ~2000 sq. foot, with a 2 stage, 3 ton, dual compressor Trane system with exposed spiral duct. In the summer it’ll hum along on first stage 1-1/2 ton compressor (think 4 barrel carb). Pull a car in and the radiant heat is crazy how hot it’ll feel, even though the air temp hasn’t changed. I do paint and bodywork on stuff and frequently spray in the same shop. I have 3- 24x24x12” deep pocket filters that last a few years with pre-filters. Garage doors don’t seal very well and leak quite a bit.
I’d recommend reconsidering those skylights, in southern Arizona. They’re basically west facing windows all day. We could power 67 incandescent bulbs with the same energy we use from the heat gained in a standard skylight. The amount of “free” light we get from skylights isn’t worth it at all. Upgrading to double or triple pane is a must if skylights are a requirement. I’ll dig up some pics of some garages from the past, and post them here.

[shavedneon]

These are in a 5000 sq. foot, the duct systems were mirrored on each half with 2 4 ton 2 stage gas packs. This one was for one of the most fastidious individuals, and is the second or third garage-mahal we did for him. I think this one was ~2010.

[dan sw fl]

I like this concept.

Spiral ducting is exposed, correct?

Why returns high and low? I'd suspect the low returns to be extremely susceptible to debris

LOW RETURN with a proper Filter grille set-up
would Not have more than normal issues
with the duct interior.

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RE: Post # 7

SPRAY PAINT / Welding ROOM with PROPER VENTILATION
should be pursued.

REF: INDUSTRIAL VENTILATION by ACGIH
https://www.acgih.org/forms/store/Pr...uctNumber=2097