I am seriously looking into installing a mini split a/c system to my third car garage which is 200 Sq.Ft. The third car garage has insulation in all the surrounding walls, ceiling and the garage door itself is insulated. I'm trying to understand what tonnage and energy efficiency I need for that space, and I'm getting some information and quotes for products and installation. I'm trying to stay within a budget of about $2k.

First off, HVAC company suggested a Daikin RKN18NMVJU
-1.5 Ton
-15 Seer rating
-Temperature regulates for room size coverage 550-800 Sq.Ft.

I'm still waiting for more information from other HVAC companies, but this first bid for $2,750 seems like overkill. I'm "guesstimating" that a 1 Ton unit will be sufficient for my needs, although, a higher Seer rating would be nice - something of about 19/20. I feel that I'm being oversold a product, when I can save money with something of a smaller unit that will satisfy my needs.

Am I off base here? What other thoughts and advice can I get from more knowledgeable people out there?

 

Mini splits can be quite pricey for what I have seen so it might be tough to keep it under your budget.

Since it is a garage, perhaps you should just install a through the wall A/C unit. They are quite commonly used in apartment buildings and elsewhere. While you need to make a larger hole in the wall, you could buy and install one for less then $1,000. FYI - 12,000 BTU's = 1 ton.

 

I'm not much of an AC guy but aren't 1.5 tons overkill for 200 Sq Ft? A sleeve unit in the wall should do the trick.

 

I agree on a thru the wall unit.

You mentioned efficiency..... how much will this unit run...... an hour two a day.... continuous ?
An 18k air conditioner will cool the garage off pretty fast but it may be a bit overkill and cycle a lot.

It's all about the heat load.

 

All good points about installing a portable unit. I want something that is super effective at heating and cooling. I also value efficient use of space in my garage which is why I'm interested in a mini split system, not to mention it's superior energy efficiency.

I'm willing to spend the extra $$ on the mini split, but I don't want to spend more than I need to obtain my goals. Would 9000 BTUs still be as effective for 200 Sq.Ft?

 

Super effective vs. super efficient.

You just now mentioned heat. That would mean you'd be looking at a heat pump system as that would be more efficient than a split unit with electric heat. I think I'd try to find something in the 12k btu range.

As you push the SEER rating up you add more electronic controls for variable speed motors and compressor.

You didn't mention the duty of the unit. Will it run continuously ?

FYI..... that part number you left for the system is only for the outside condensor.... not a complete system. The RKN series is cooling only. RXN is heat and cool.

Page 20 shows the systems........ daikin-ductless/Daikin-2015-br.pdf

 

Nobody mentioned a portable unit. There are portable A/C units that just use hoses that intake and exhaust air (not a good option in your case) and then there are through the wall units. Through the wall units look like a window A/C unit but are installed in a sleeve that is installed through the wall.

You did not mention that you want heat. A quick look also turns up wall A/C units that also have heat. Just search "through the wall air conditioner heater" Just food for thought: http://www.livingdirect.com/frigidai...efault,pd.html

 

It will not run continuously. The garage will be an extra work space for me, and a place to put my two dogs during the day while my family works or is gone. It will only need to run for maybe on average - 2-3 hours a day.

I didn't realize the RKN series was cooling only. Thanks for bringing that to my attention. Ideally, if I didn't belong to an HOA, I'd install a window unit, since I do have a man-door with a window that leads to my backyard, but my HOA doesn't allow window units. Since the man-door is on the side of the garage (still visible from street and sidewalk), I doubt many would notice a window unit, but since nobody else in my immediate neighborhood has one from what I can tell, I don't want to risk the off chance that someone with knowledge of proper HOA rules would see it and report the violation.

 

Ah... HOA changes everything. I understand going with the mini split. Thanks for the clarification.

 

Since the room is all insulated, 9000BTU is good enough, mini-split is more expensive, but shop around a few more places see if you can get a better deal.
I like mini-split because they don't make much noises at all, much better than a window unit.

 

Really late to the game here....but it's really only 200SF? I had a storage shed bigger than that.