The 12k BTU LG minisplit is up and running so I thought I'd relay my experience and costs. I've got just under $1700 invested and two full days of labor. Overall, I'm thrilled to finally have AC; I wish I could have done it sooner.
I bought the LG LS121HSV2 inverter heat pump from AJ Madison for a little over $1200 with free shipping. They knocked 5% of their price when I ordered over the phone. The 15' lineset was $90 after shipping from PexSupply. I wall-mounted the condenser and the bracket was $55 from hvacguysonline on Ebay. Additionally, I spent about $150 at HD for the breaker, Romex, THHN, disconnect, flex conduit plus Liquid Tight fittings, sleeve anchors, dryer vent, vinyl gutter downspout and clips, plus a couple new bits for the hammer drill. HVAC dude was $150 to cut, flare and connect the lineset then evac and start up. Yeah, I could have put that towards tools and a vac pump+gaugeset. Hindsight...
I'm in central Florida. I love it but it's a humid, bug-infested swamp. Leaving the doors open only works for a few months of the year. The space is 20x24x12 with one overhead door and one fiberglas swing door. No windows. Construction is uninsulated block but the roof is foamed with 3" of closed-cell. The attic stays within 10°F of the garage temp during the hottest days. The east-facing overhead door is insulated and gets full morning sun for 3 hrs. South and West walls are mostly shaded. I figured 12k BTU would do it since I'm mostly trying to dehumidify while knocking the temp down a little. For reference, the garage stayed low/mid 80's this summer but humidity is often over 80%. A portable dehumidifier would dry it out but heat it to 90F by afternoon. If 12k (actually rated 11.3k BTU) proves inadequate, I'll get on here and admit it.
Installation was as described earlier in this thread and others. My only real challenge was routing the electrical and copper around the block cells that are concrete filled. Where I chose to put the condenser and evap preserved wall space for my particular needs but the installation took longer and isn't as elegant as I would have liked.
I predrilled the hollow block then knocked perfectly round, neat holes thru it with a hammer. Then I beat and chiseled much larger, irregular holes after trying to stuff the lineset, condensate drain and 14-3 Romex thru it. The outside hole is about 6" below the inside hole for drainage and ease of bending the lineset. The lineset and drain are hidden inside a 2x3 vinyl gutter downspout that I slit full-length with a utility knife and sleeved over the lines. It's secured with plastic gutter clips tapcon'd to the wall and topped with a dryer vent that's butyl caulked to the stucco. I foamed around the block penetrations before adding the vent cap. I'll scuff the vinyl, prime it with some Grip-n-Seal, then make it disappear with house paint. Momma won't even see it.
The condenser wall mount bracket was easy to install with four 5/16" x 1-1/2 Redhead sleeve anchors. The condenser ends up 5" from the wall but I didn't find any brackets that provided the 12" mfg suggested clearance. The copper lineset was much easier to bend than I expected and came preflared and capped. Two surprises: I didn't know the evap was shipped pressurized so when you remove the caps, it hisses. I had a brief, "ohshit" moment thinking I'd released refrigerant. Second, there was an uncomfortably long, 2-3 min delay before the condenser fan and compressor started. The evap fan came on instantly but the outside unit had me concerned.
So, how's the thing work? Money! On a humid 88° day the garage started at 81° and 74% RH and was at 79° and 52% RH in 30 mins. Water POURED out the drain. Both units are unbelievably quiet in high and barely noticeable when it throttles back. The condenser sounds like a mini fridge and from 10' away I can't hear it over the cicadas. Initial performance is exactly what I'd hoped for and the installation is discreet. Plus, there are no large holes that could be security concerns.
I'll update with pics later and any noteworthy performance specs. BrIan
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