Mini Split Specific Requirement Recommendations

[abgiles]

Ok, still a newbie to this site, but not to forums, and I know to search before starting a new thread. To this end, I can say that I have searched and read a ton about these things, and can't seem to find the answers I'm after, so please don't berate me.

I live just outside of Jacksonville, FL, and will be in my shop most days during the summer and winter, as I travel during the spring and fall. No, it doesn't get that cold here in the winter, but days with the lows in the low 30's aren't that uncommon, and I don't need to tell you about the hot, humid summers.

My shop is a Carolina Carports 30x60 with 12 foot sides, fully insulated with closed cell spray foam insulation, and full electric. I have 3 ceiling fans that move quite a bit of air, and want to hit up a mini split. On one end, the last 14 feet are a man cave that is isolated and insulated from the remainder of the shop, so as to be able to allow me to keep it at a different temp than the rest of the shop (it also doubles as a guest suite, so night time sleeping needs to be chilly).

I am looking for a mini split that offers 3 zones, DIY install, and a DRY mode to just drop the humidity without cooling on those days that it's not so bad temp wise, but is still muggy due to the humidity.

I've seen the MR Cool DIY kits, have read the reviews, etc.. but can't seem to locate one that has multi zones. I've contacted several HVAC contractors here locally, and they don't want to mess with systems they don't install for some reason, so buying one that's not a DIY kit might not be an option.

I'm looking for recommendations/experiences, and any thoughts you have on this.

I am mechanically and electrically inclined, so don't mind if it's not a DIY kit, if you've got a great one that you're super pleased with. I'll figure out the evacuation and filling somehow, but would love to hear your experiences with different brands.

 

[sreeb]

I can't speak to your specifics but I think you will be better of with 3 single zone units.

What drives the requirement for multizone?

 

[OzarkMan]

I ended up doing a single 3 ton unit for my 1088sq foot garage. I am sure even in the hottest of AZ summer days it will be an icebox in there. I oversized it for my needs to quickly cool down a hot space when needed. I bought an LG unit with ceiling cassette and am doing a self install. I have all the HVAC tools including a refrigerant scale and R410A since the lines are limited to 25' and I have 65'. I will need to add 27oz of refrigerant according to the manufacturer but my SMan 460 will tell me exactly what I need.

 

[PoorOwner]

I would do 2 single unit, big and small. Not sure what your square footage partitions are..

3 zone is a pain because if there is a leak with one connection your whole system goes down. Remember there is only 1 compressor and 1 inverter, the compressor will run at a highest demanded speed and the lower demand zones just blows on and off to regulate temperature. As far as I know these non-commercial mini splits do not throttle refrigerant to different zones. So having individual systems for the rooms will be superior in many ways.

Generally you are going to have a hard time finding someone to install a multi zone unit you bought online.

 

[theoldwizard1]

Most of the big name brands do not sanction DIY installs. That does not mean that you still might be able to do 90% of the work and then have a registered dealer do the final hook up and submit the warranty paper work.

One thing I have recently learned is that multi-zone system have much lower SEER/EER ratings than single zone. Big difference in cost, but you might want to consider a total separate system for your man cave/guest suite.

I ca not say that I have seen any controls that include a DRY/dehumidify setting, but I understand its importance in your area !

 

[DHCrocks]

I am looking for a mini split that offers 3 zones, DIY install, and a DRY mode to just drop the humidity without cooling on those days that it's not so bad temp wise, but is still muggy due to the humidity.

Dry mode on a mini split will cool the space, quite a bit in fact. Say your outside temperature is comfortable in the low 70's and you don't need cooling but want to drop the humidity. The minisplit in drymode will function by running at a low speed to remove moisture but it also cooling the air at the same time. over a period of time the humidity will drop but so will the temperature. When I put mine in drymode it after several hours the room get very cold.

 

[yeldogt]

When properly sized the dry mode works .. you will get some cooling ... it's all a question the temp and humidity at start. Typically, you don't turn the units off so they keep the space within limits.

I have two multi head systems -- they work great .. Mitsubishi. One is two wall and a floor and the other has one wall and two cassettes. The single head units can achieve the highest efficiency -- there are benefits to both types. Most people don't want or can not have three compressors around the house .. the multihead also have the ability ramp above 100%.

I have never seen a DIY multi -- with the quick connect fitting requiring no flares and evacuation

 

[Jackfre]

Dry mode works by running at a low enough rate to keep the coil cold so the moisture can condense out. With the modulation and proper sizing it is economical to operate. Whichever brand you choose be very careful to compare and understand the specs on the units. I am most familiar with Fujitsu and annually I download their catalog. I am always surprised at the differences in models of even the same size. Compare the costs of multi's vs single units against efficiencies. Most of the top brands are wireless capable so you should not have to oversize for quick cool down. You can simply dial it up and turn it on in anticipation of you arrival.

 

[abgiles]

Thanks for all the responses. I am not dedicated to a multi zone unit, as I don't mind separate compressors. I do like that one line going down won't kill the entire system if I put in 2 different units. The shop size will be 1500 sq ft and the man cave will be 300 sq ft, so considering a 2K and 1K unit. I like the idea of doing the main part of the install myself and having a local company do the final hookups, just have to see if that gives me the warranty.

 

[Jackfre]

For the 300 sq ft I would not go over 9k. That is plenty of capacity even in your area. For even cooling in your larger area, set a couple evaps kitty-corner on opposing walls about 25% of the way up the wall. That will give you the best balanced air flow/temperature. Your 2 ton should do there.