PTHP or Split-Mini???

[varunner]

Would enjoy hearing some feedback concerning this. I'm getting close to having to chose between these two systems. My garage is 32 x 44 x 12, walls are SIP panels with a truss roof. The garage will be insulated well, but the biggest concern is how well the garage doors will seal. It's located in VA, so it will be up in the nineties in the summer and usually the thirties in the winter, with a few days in the twenties. One of the biggest considerations will be to keep the humidity within reasonable levels.....no rust build-up. Normal calculations(1400sqft) would put me at needing a 3ton system, but I'm just not going to put a bigger system in my garage than I have in my house(2.5tons). If the temps end up being a little too cool in the winter or too warm in the summer, not a problem......its a garage. The biggest PTHP I've seen is 1 ton, so I'd need 2 of these, haven't fully researched the split-mini yet. One advantage of the PTHP is that there isn't an installation cost, just cut 2 holes in the wall, plug in and push the button. With the split-mini, I would need a hvac tech to evacuate the lines and back-fill with freon. thanks in advance

Brian

 

[rickairmedic]

Brian we are not that expensive and I think with the size of your garage you would be much happier with a mini split or 2 over the ptac units .


Rick

 

[varunner]

Yeah, I suppose we're not talking about that much for installation. With installation aside, do you think that 2 PTHPs and 2 minis of the same capacity would perform equally? I'll have to compare the cfm of them too I suppose.

 

[rickairmedic]

Brian the mini splits are exactly that a mini split system just like in your house only no ductwork . I think they would perform better for what you are wanting to do than the PTAC units would and you can mount the inside halfs pretty much anywhere with the PTAC's you are gonna give up wall space no matter what you do and I know at least in my shop there isnt enough wall space as it is without giving up any to an HVAC unit.

Rick

 

[sneezer41]

mini split

they are getting really cheap

 

[sneezer41]

Oh, and I ran a 9000 btu and then 24000 btu in a 900 sq ft shop with so so insulation, sun loading, and a whole machine shop running in it. You do not need to be 65, just 80 and dehumidified. I'll bet 1 1/2 to 2 ton will be perfect

 

[anojones]

I have PTAC units in my garage in two well insulated spaces- they are heat pumps with back up heat. I haven't used them much as the drywall was just hung this week- they worked very well to heat the place up, I haven't used them for cooling yet. At the time I was looking a mini-split was running me twice as much, they may be cheaper now. It seemed most of the mini-splits were cooling only, and heat was important to me. One thing I didn't think a lot about with the PTACs is noise, I'd bet a mini-split would be pretty quiet in comparison. In retrospect, I wish I'd at least looked more carefully at a mini-split option and maybe god a bid from an HVAC company.

 

[varunner]

thanks for the info. I should have prices in about a week or so. I have plenty of wall space. One thing I do like about the split-mini is that I have more flexibility in where the air handlers will go. Having the PTHP on the back wall, I question how even the temps will be, especially near the front of the garage.

 

[rburke65]

Hi guys. For us novices, what is/are "PTHP" ?

 

[varunner]

package terminal heat pump. they're used alot in hotel rooms, the unit on the floor, half in the room, half outside.

 

[JMURiz]

I'd go with the mini-split because you can get them in 14 or 16 SEER ratings, so they will be cheaper to operate in the long run. I was looking into PTAC for mine as well, then I found out about the mini-splits and will be going that route.

 

[varunner]

I have PTAC units in my garage in two well insulated spaces- they are heat pumps with back up heat. I haven't used them much as the drywall was just hung this week- they worked very well to heat the place up, I haven't used them for cooling yet. At the time I was looking a mini-split was running me twice as much, they may be cheaper now. It seemed most of the mini-splits were cooling only, and heat was important to me. One thing I didn't think a lot about with the PTACs is noise, I'd bet a mini-split would be pretty quiet in comparison. In retrospect, I wish I'd at least looked more carefully at a mini-split option and maybe god a bid from an HVAC company.

How big is your garage, and what size are your PTHPs?

 

[anojones]

I have two insulated spaces separated by an unheated garage, it's a pole barn construction. Each section is about 550 sqft of conditioned space and the PTACs are 15K BTU with a 5K watt back up heat strip (240V 30A, rather than a 20A units). I forgot one of the reasons I didn't go with a mini-split is I had two conditioned spaces that were a fair bit apart, making the mini-split a fairly expensive option. The PTACs are an easy install, I installed the sleeves during construction and just slid in the units. They are easy to replace down the road. They also have a nice feature which is freeze protection (I have some plumbing in the garage as well), the unit kicks on when the temperature drops below 40 F and heats it to 43 F which is nice when you don't need the place heated all the time (the feature can be turned off as well).

 

[JohnZ]

I have a 42,000-BTU Mitsubishi A/C-only mini-split in my 44' x 58' x 12' super-insulated garage (with two 18' x 8' insulated sectional doors), and it cools 2550 sq. ft. with no problem, even when it's in the 90's outside. Both the inside air handler and outside compressor/condenser are scary-quiet.

http://www.villagephotos.com/pubbrowse.asp?folder_id=1411059

 

[varunner]

Sounds like you both are happy with what you have. I have someone coming over this weekend to give me a price on a mini-split and I'll be getting prices on the PTHP too. Sounds like both will work....we'll see how the prices shake out.

thanks for the info
Brian

 

[Kirby]

I was going to start a new thread, but will post here. I have similar heat/cool questions. I am starting a 30x36x10.5' detached garage, fully insulated(6" walls). I want to put in a thru-wall (electric) unit. Recommendations for type of unit and btu size would be appreciated. I have looked at Amana and GE both 12000 and 18000btu. Thank you all. Kirby

 

[Loogie]

I just installed a Sanyo KHHS2672R Mini Split system in my 30x25x10' detached garage/woodshop. I haven't actually powered it up yet, since the drywall is just being hung now. I got this model specifically because it was the ONLY mini split that I could find that had a backup electric strip heater for those really cold days. I have running water and can't afford to have things freeze. It is 15.9 SEER and has an HSPF rating of 10.3 and will extract 7.3 pints of water per hour - much higher than most of the others I found. It wasn't cheap though. I like the mini-split systems because they all have a "DRY" mode, so during the summer you can just run it in that mode to keep the humidity down and then turn it to "COOL" when you go into the shop.
The Sanyo systems are comparably built to the Mitsubishi's, but are quite a bit cheaper. I've also hear good things about the Amana systems.

 

[ptacguy]

Im sure the guys at SunEcho can answer any questions you have about the mini-split and ptac units. I'd give them a call 866-600-3300.
http://www.sunechocorp.com/