Mini Split. . Are you happy?

[Enjoytheride]

Ok. . so my 30' x 40' x 10' in SE Pa. is built and at the stage in committing to heat and possibly ac source. . . I'm having a hard time moving forward with a mini split because I'm not sure I will be happy with the results and longevity of the units.

Those that went with a mini split in their shop/garage. . . Are you happy with the results?

https://www.theacoutlet.com/38mgrq3...I34pSNQYf_jSeXqJpm-6Gb8MJYg3h9RcaAtPqEALw_wcB

 

[theoldwizard1]

Sizing is a big issue. Something that big is probably going to require multiple aire handlers and maybe even some additional fans.

What kind of insulation do you have ?

A quick skim of that models specs and the COP drops off very quickly below 20F. You might want to check out some other brands. Mitsubishi and Jujitsu are the biggest seller, but even on those, you have to be careful what you buy to get good heating in cold weather.

 

[Enjoytheride]

It would be 3 head units
12,000 btu each across the back wall.

R-19 in the walls and ceiling with be loose. .

 

[wirt]

The colder it gets the weaker they are, and the fans don't blow very hard to begin with.

That's my experience heat wise, not sure how it will work AC wise as I haven't used it in summer yet.

I bought the mini for AC but got a super deal on the one I have with heat, it does ok if it's 50 degrees out but really falls short after that. So I just use my hanging furnace.

 

[ItsNemo]

Why would you opt for a mini split for heat and only possibly AC? Their real benefit is the fact that they can do cooling.

 

[Enjoytheride]

I would use the mini split for heat and ac. . if I go that direction. Otherwise a Hot Dawg or Reznor heater just for heat.

Why would you opt for a mini split for heat and only possibly AC? Their real benefit is the fact that they can do cooling.

 

[gtae07]

I've been real happy with an 18k Mr. Cool DIY so far. But, heat isn't too much of a problem in the winter; we don't get that cold. Working with AC, now, that is nice.

 

[James-W]

I have a 60,000 BTU Hot Dawg hanging heater and I have a window air-conditioner in my 24X36X8. I am very well satisfied with that setup.

 

[dsimatt]

Not a garage but in my house, yes I have been very happy with my mini split and it puts out plenty of heat even in the negatives....just takes longer to put out heat. That said I have the Mitsubishi hyper heat which is one of the most expensive but I think its performance justifies the cost.

I only have a single unit and bought it mostly for AC which you have to remember it's a single source so takes a lot longer to cool my place then forced air would but that wasn't a option.

 

[McFarmer]

Good AC, very poor heater.

They say it works down to 10-20 degrees. Our experience is nothing below 30, and very little then. Our radiant heaters are n all winter.

 

[BoostAddiction]

I've been very happy with the minisplit in my garage. I only use it when I want to work out there when the weather is cold or hot- and it does a great job.

Lately, they have gotten even better, with incredible COPs, and I wouldn't be too concerned with what someone with a 10 year old unit thought- the new ones are just so much better, if you look carefully at the specs.

 

[ghnl]

I like ours. But as others have mentioned, they are not great at supplying heat when outside temps are below ~ 30F. Here in NC the number of days that are that cold is small. Some units have built-in electric heating strips - but that tends to be an expensive way to get heat. In the summer the A/C is great.

 

[James-W]

As far as heating is concerned, with the price of natural gas being as low as it is, if it is available I would find it difficult to go with anything else. I don't have a crystal ball but I seriously doubt the cost of natural gas will go up very much in the near future.

 

[Kaizen]

Good AC, very poor heater.

They say it works down to 10-20 degrees. Our experience is nothing below 30, and very little then. Our radiant heaters are n all winter.

Ditto. Find me cool not worth to run for heat under forty degrees. Awesome for ac and humidity control.


Sent from my iPhone using Tapatalk

 

[Enjoytheride]

Yeah. . I'm thinking a Hot Dawg or Reznor for heat.. AC and humidity control is not worth the $4500 cost for the mini split.

 

[finn]

I have a split in the house, but only use the heating for the shoulder season, before it is consistently cold enough to fire up the propane boiler.

I’d never consider a mini split for a shop or garage.

 

[tom-ky]

We put a mini split in a man cave in late November. We have had some zero weather and kept a 450 sq. ft. area heated during that weather. Not sure how it will do with cooling yet.

 

[whatuusay1]

Yeah. . I'm thinking a Hot Dawg or Reznor for heat.. AC and humidity control is not worth the $4500 cost for the mini split.

$4500 - Yikes. I spent about $1800 for my 2Ton LG split unit (self install) and its been wonderful. I've had it 6-7years now and makes the garage an extension of the house. I don't turn wrenches or work in the garage that much but it keeps the cars warmer, and makes the space usable when i'm out there I'll often minimally heat/cool with it and turn it up when needed and it does that very well. I love working out there in july/aug or Jan/Feb when its miserable hot or bitter cold. My unit will work to about 20 degrees, and then the performance tappers off. I knew that when buying it but we don't get that many days like that so its not much of an issue. In its operating temp it kicks out heat/cold very effectively. Even if you only bought 1 (for 1800 i'd think cutting the heat in the summer would be well worth the money. You can check out ACWholesalers.com for self install kits, its seriously not that hard. I hired a local HVAC to connect the lines for $100. I plan on buying another when we build our next house.

The only real issue i've had is the unit is a bit noisy, but at 6-7years old (in a dusty garage) i cant say i'm all that surprised. I also dont clean it often (i think they recommend cleaning them every 3-6 months).

 

[Enjoytheride]

$4500 - Yikes. I spent about $1800 for my 2Ton LG split unit (self install) and its been wonderful. I've had it 6-7years now and makes the garage an extension of the house. I don't turn wrenches or work in the garage that much but it keeps the cars warmer, and makes the space usable when i'm out there I'll often minimally heat/cool with it and turn it up when needed and it does that very well. I love working out there in july/aug or Jan/Feb when its miserable hot or bitter cold. My unit will work to about 20 degrees, and then the performance tappers off. I knew that when buying it but we don't get that many days like that so its not much of an issue. In its operating temp it kicks out heat/cold very effectively. Even if you only bought 1 (for 1800 i'd think cutting the heat in the summer would be well worth the money. You can check out ACWholesalers.com for self install kits, its seriously not that hard. I hired a local HVAC to connect the lines for $100. I plan on buying another when we build our next house.

The only real issue i've had is the unit is a bit noisy, but at 6-7years old (in a dusty garage) i cant say i'm all that surprised. I also dont clean it often (i think they recommend cleaning them every 3-6 months).

Yeah. . The Carrier unit (link in my first post) is from ACOutlet. I'm sure I could find a slightly cheaper unit but but at what expense in the long run.

 

[theoldwizard1]

The colder it gets the weaker they are, and the fans don't blow very hard to begin with.

That's my experience heat wise, not sure how it will work AC wise as I haven't used it in summer yet.

You have to be very careful selecting the proper mini-split for heating application. Performance start to drop off on some around 30-40F. Others still give 100% until down below 0F.

 

[theoldwizard1]

I would use the mini split for heat and ac. . if I go that direction. Otherwise a Hot Dawg or Reznor heater just for heat.

Sizing your system is key. For a space that large you will need multiple air handlers and possibly some additional fans.

You may want to consider some kind of portable back heat source in case of a power outage or even to raise the temp quicker.

 

[theoldwizard1]

Yeah. . I'm thinking a Hot Dawg or Reznor for heat.. AC and humidity control is not worth the $4500 cost for the mini split.

If AC and humidity control are not a priority go with a nat gas or propane furnace.

The big win for mini-splits is (effectively free installation of AC and very low cost of operation in the "shoulder" heating season.


One thing that is never brought up, is that with a well insulated building and a top of the line, high SEER mini-split (around 30) and solar panels with a grid tie inverter, you can get your energy consumption bill down to close to ZERO dollars. Yes, it does require a lot of $$$ of front, but if it is for a "forever" home, it is worth it.

 

[justinjoyal]

Good AC, very poor heater.

They say it works down to 10-20 degrees. Our experience is nothing below 30, and very little then. Our radiant heaters are n all winter.

That’s because you have a very entry level unit...

Most « standard » models these days are effective at heating down to ~ 5-10F..

Some mini-splits provide 80% output at -22F... COPs around 2.

 

[JBudd2]

I self installed a mid level LG with two heads, one 12k and one 8k in my shop two years ago.here in Nebraska it gets cold in winter and hot in summer and I love my mini split. Even down to zero it is putting out some heat. Temp might drop to fifty. Below zero I stay in the house. In summer it trims the humidity so I can work with my glasses on. Shop is 26x44x9 and well insulated.

 

[Angelfire]

I have a 32x40x10-12' space. Went with a 24k unit with a 9k head in the lower ceiling area and a 15k in the higher space. Installed myself but it's only been running since last summer. AC was fantastic. Now we're in winter, and well, we've had a very unseasonably warm winter. Had a few nights in the low twenties and I found the heads actually got the place to temp and then stopped blowing until the temp dropped below a certain threshold (didn't make note of that "threshold"). So based on that little bit of data, I've been quite happy with mine. How would they operate at 5F? Time will tell. That being said, I have R23 in the walls, R60 in the ceilings, and the area is pretty well sealed up with the exception of the garage door. Few leaks exist there still.
Cheers.

 

[Jackfre]

Good AC, very poor heater.

They say it works down to 10-20 degrees. Our experience is nothing below 30, and very little then. Our radiant heaters are n all winter.

This is a problem in the mini-split field. I have been talking with contractors who are going out on "low heat" calls and are finding that the original installer put in a unit that did not have the very low temp specs to do the job. Make sure you know what you are buying.

The multi head units are not as efficient as the singles. Compare the pricing/specs of your multi against singles. If I was doing your building, assuming good insulation and construction I'd put in two 12's. That is 600 sq ft/ton and I think would give you good comfort and dehu. I would locate the evaps on opposite walls kitty corner from each other. That is a good circulation pattern. Efficiency of my 12 is 25 seer and 12 hspf. My dual is 16.5 seer and 9.5 hspf.
Rough in the gas.

 

[minytrker]

Best thing I bought! Have a 24k or 26k dont remember in the 24x41 portion of the shop. In Texas in the summer I can get it down in the sixties (set at 74 normally) and we dont really have winter but it did get in the twenties here for a few days and the shop stayed at 74 with the heat on. It can maintain the heat but if you open the 10x10 doors it takes a long time to re-heat the whole shop. If I pull a car in or out and its really cold I will fire up my kerosene heater for maybe 5 minutes and the shop is back to temp and then let the minisplit maintain it.

 

[theoldwizard1]

This is a problem in the mini-split field. I have been talking with contractors who are going out on "low heat" calls and are finding that the original installer put in a unit that did not have the very low temp specs to do the job. Make sure you know what you are buying.

Yep ! BUYER BEWARE !

The multi head units are not as efficient as the singles. Compare the pricing/specs of your multi against singles. If I was doing your building, assuming good insulation and construction I'd put in two 12's.

2 high SEER singles (>30) are more efficient, but the cost difference is a lot. It is not trivial figuring out the pay back time.

A bonus of 2 singles in an open area, during the "shoulder months" you probably only need to run one and maybe some extra fans !

 

[finn]

Yep ! BUYER BEWARE !


2 high SEER singles (>30) are more efficient, but the cost difference is a lot. It is not trivial figuring out the pay back time.

A bonus of 2 singles in an open area, during the "shoulder months" you probably only need to run one and maybe some extra fans !

Our local utility has a $1500 rebate going if you are replacing an existing electric furnace with a mini split of 21 or greater seer in a residential billed structure, and have the unit installed by a licensed contractor.

Electric baseboards apparently count as an electric furnace, per my contractor, and A customer may qualify for multiple units in the same building.

Has me thinking.......

 

[yeldogt]

I don't think you need three heads to cover the space. Two would be great -- I had a studio starting out that size (one room) with a wall AC unit that cooled fine. electric baseboard.

Do you have NG available?

Purchase the correct mini and it will do the job .. all the posters talking about poor low temp performance .. don't have the correct units. Mine have no problem heating in zero degree weather .. none ... it's hot air coming out .. they work. I have mini-splits in multi places and I'm doing them in part of my new house.

I have a weekend house in PA w/o NG -- with PECO electric rates it's a wash with propane at many times. But I want AC -- so you get the heat with the mini. No space for a conventional ducted unit ... since I have propane service I also have a 40k cabinet unit (they sit on the floor)

The single vs multi-head is often a question of what will fit ... most people don't want multiple compressors outside -- but, the multi are not often any cheaper. Will depend on application -- it's all about the specifications. I have two 3 head mitsubishi systems ... a single LG and a single Fujitsu (all different places).

I believe the single hyper heat mitsubishi are still the highest efficiency in the line. Frankly -- I can see the wisdom in having two separate units in a garage space where the compressors are on the back side and not seen ... especially if DIY. With my two 3 head systems -- I had one great spot for a compressor ... did not want to have two or three outside.

 

[bonneyman]

Heat pumps are a compromise. You can make a dang good straight A/C, and there are awesome heating units out there, but to get a unit to do both is a set of compromises. Invariably the manufacturers favor one characteristic over the other when they make a heat pump. That's why many brands make one "style" for Kansas and another one for Nevada.
Many companies push HP's here in Arizona because our cooling load is enormous and our heating requirements are quite lax. Much easier to make a "Heat Pump" perform well under those terms. And yet the biggest complaint I have from customers is "not enough heat"! Folks migrate here from northern states where they had gas or oil heat, and - when the temp drops - their heat pump "blows cold air".
Mini-splits only add to the compromises. Noise, airflow, decor, placement, outdoor ambient requirements, building application. Not saying it's impossible, but it's damn hard for a manufacturer to market a unit and guarantee it'll work in every place the customer stuffs it. Probably wouldn't be a bad idea to get a contractor you trust to come out and measure the space and make recommendations on what unit he feels will provide the heat and cool you need.

 

[Jackfre]

Yep ! BUYER BEWARE !


2 high SEER singles (>30) are more efficient, but the cost difference is a lot. It is not trivial figuring out the pay back time.

A bonus of 2 singles in an open area, during the "shoulder months" you probably only need to run one and maybe some extra fans !

Granted it has been a few years since I have run the numbers, but when I did the cost break point was when you went to a triple. I actually bought the dual and single (25 seer, 12 hspf) for less than I could buy the triple for. Front end cost is obviously a consideration, as is your electrical set-up, but again...check all options. How do you use the space? The advantage, besides redundancy, is I have with the set-up in the house is that the dual only does the upstairs. I have never run them for heat upstairs (gravity handles the second floor) and usually only run the fan and in high summer for cooling. The hi-eff single runs year round, pretty much. As to cost of operation, here in CA, where elec. is not cheap, to run my home lights, heat, well, all my shop power, our electric bill was $135 in Jan. Shoulder seasons run about $80. Now...I also do run my Rinnai DV. Total gas for the year, heat, DHW and cooking is about 250 gal of propane.

 

[theoldwizard1]

Our local utility has a $1500 rebate going if you are replacing an existing electric furnace with a mini split of 21 or greater seer in a residential billed structure, and have the unit installed by a licensed contractor.

Electric baseboards apparently count as an electric furnace, per my contractor, and a customer may qualify for multiple units in the same building.

I can not imagine living in the UP and living with electric baseboard heat ! Youe electric bill must be unbelievable !

 

[finn]

I can not imagine living in the UP and living with electric baseboard heat ! Youe electric bill must be unbelievable !

We had baseboard electric heat when the building was originally erected as a seasonal cottage. Highest monthly power bill back then was in the $300+ Range, although most of the winter the room temp was set to less than 50 degrees. Makes propane seem like a bargain.

Main heat now is propane staple up radiant, except for the basement. I’m getting quotes for a mini split with low temp heating capability for the basement. Don’t really need a/c down there, but dehumidification capability would be nice in the summer. I doubt running a heat pump uses a significantly larger amount of electricity than running a dehumidifier almost constantly.
A mini split wouldn’t be a cost effective solution without the $1500/ unit rebate. I do have a three head Mitsubishi in the upper levels for summer a/c when needed, and shoulder season heating, when in floor radiant doesn’t work well because of daily temperature swings (even with outdoor control)
Winter temps here are typically in the twenties with nights dropping to the single digits, but well below zero is not uncommon for a week or two. Our temperatures are moderated by the proximity to Lake Superior. It gets cold enough that a unit like the Mitsubishi Hyper Heat is probably a necessity if one is relying on a mini split as a sole heat source.

 

[grkmec]

I am going to start construction on a ~1,700 sq foot garage in CT, and thinking about using this for HVAC:

http://www.fujitsu-general.com/us/products/split/wall/asu30rlxeh.html

"Fujitsu XLTH units feature large heat exchangers and high
capacity compressors. This gives our XLTH heat pumps the
ability to extract heat even at very low outdoor temperatures.
For example, at an indoor setpoint of 70°F, all RLS3YH and
RLFFH models can deliver 100% or more of their rated heating
capacity down to 3°F. All XLTH models also offer superior
heating performance down to -15°F outdoor temperatures."


Walls will be 2x6 construction and will use 5" of closed cell foam (R30). Then probably go R60 in vaulted ceilings. I figure 32k of heating BTUs will be enough to keep the place in the low 60s during the winter when I need to heat the place up and keep it at a min of 55 degrees.

Was thinking just a single unit for cost / efficiency.

 

[theoldwizard1]

We had baseboard electric heat when the building was originally erected as a seasonal cottage. Highest monthly power bill back then was in the $300+ Range, although most of the winter the room temp was set to less than 50 degrees.

Typical heat for a seasonal place. 50 degrees is down right uncomfortable to live in and maybe even work in. If you were just trying to keep the pipes from freezing, thats fine.

I do have a three head Mitsubishi in the upper levels for summer a/c when needed, ...

I have seen Yuppers MELT when they come down to where we trolls live and the temperaturs are above 80F !

 

[theoldwizard1]

Walls will be 2x6 construction and will use 5" of closed cell foam (R30). Then probably go R60 in vaulted ceilings. I figure 32k of heating BTUs will be enough to keep the place in the low 60s during the winter when I need to heat the place up and keep it at a min of 55 degrees.

"You pay for insulation ONCE ! You pay for energy every time the thermostat calls for heating or cooling !!"

 

[PoorOwner]

I find that dual zone units are pretty much 2x the cost of 2 individual units, e.g. two head 9k or 12k units.

I don't know about other brands, for the Mitsu, the zone with higher demand become the "master", and it makes the compressor run at that higher speed needed for the master zone, then the other zone is the slave and the slave will blow the fan intermittently on and off, similar to a gas furnace, but sometime as short as less than a minute, because the slave coil will overheat the room if blowing continuously.

It does keep the temp properly that way.

For a shop that is actually one big room, going to dual zone you are using a quite a bit of energy pumping to the 2 handlers, because the slave zone doesn't really need all that heat, it just heat the coil hotter than it needs and blow it once in a while.

Maybe the higher end system also have variable valve or something, (city multi, etc) where you would serve different hotel or apartment rooms, but I doubt anyone here trying to AC their garage is getting into this.

If you can help it, just put a SINGLE zone unit near where you work the most and use a floor fan or ceiling fan to even out the temperature. Or add single zone units as needed.

BTW contractors are not giving much of a break in installation costs with multi zones, call and ask for a quote installing a 3 or 4 zone system and you shall see.

 

[Razberry910]

Ok. . so my 30' x 40' x 10' in SE Pa. is built and at the stage in committing to heat and possibly ac source. . . I'm having a hard time moving forward with a mini split because I'm not sure I will be happy with the results and longevity of the units.

Those that went with a mini split in their shop/garage. . . Are you happy with the results?

https://www.theacoutlet.com/38mgrq3...I34pSNQYf_jSeXqJpm-6Gb8MJYg3h9RcaAtPqEALw_wcB

Bringing up an old post! I'm in NE Ohio and looking to build a shop exactly like yours. Did you go with the mini split? If so how do you like it and what size unit(s) did you go with?

 

[brianh]

I installed two Pioneer 12000 btu mini spits in our house last fall, I have been very happy with the heat output at -10F they were still producing heat just fine they were pulling 900 watts each at -10 when it is in the 20's they average 500. They have come a long way in the last few years.

If I did not make so much dust in my shop I would definitely install them there.