Who's using a mini split in youz shop?

[littleboss]

I live in north Texas. I put a Pioneer 24k in my shop. I previously had a wood stove, 50k btu hanging shop heater (propane) and a 2 1/4 ton window unit. (propane heater is still there). I typically leave the shop at 60 during the winter and heat it up before going out there. During the summer it's on 82-85 if I am not out there.
What I have found is that
1. In the winter I don't like the "cold" air that the mini blows. I am used to hot air from the propane heater or the woodstove. The mini blows warm air when you first turn it on but then as it reduces capacity the air is cold. I don't like that at all.
2. If I leave the thermostat low until I am ready to work then it takes hours to get it up to temperature. Now the propane heater IS twice as big so that makes some difference of course. Also the propane heater blows air all the way across the shop. The mini on high blows about 2/3 as far. the Mr Heater only blows hot air no cold air!
3. In the summer the mini doesn't cool as fast as the old window unit did either so I have to turn it on hours in advance.

So for me I use the mini in the winter to keep the shop at 60 as it's far cheaper than propane. When I start to head to the shop I turn the Mr Heater on to warm it up quickly and then run it. When I leave I cut it off and the mini takes over again.
In the summer I either have to leave the thermostat on 78 or wait a long time for it to cool down.
In my opinion I wouldn't have bought it just for heat but it's over twice as efficient as my window unit was so it's good for cooling.

 

[ericm]

None of my mini splits (Mitsubishi in the shop and Daikin in the house) blow cold air when in heat mode. Sometimes it's not much warmer than ambient, sometimes it is. It's never like a gas heater blowing on you. Both makes have a ton of settings for air direction. I set those so there's not too much air blowing on me but you can also do the opposite. The Mitsubishis have sensors that will try to make the air blow where the people are. I think this would be better for cooling than heating. Mitsubishi also has a far distance setting which might help get air across the shop.

I put fans in the shop to help circulate the air though the mini splits seem to do an ok job at getting across 40' on their own.

 

[littleboss]

None of my mini splits (Mitsubishi in the shop and Daikin in the house) blow cold air when in heat mode. Sometimes it's not much warmer than ambient, sometimes it is. It's never like a gas heater blowing on you. Both makes have a ton of settings for air direction. I set those so there's not too much air blowing on me but you can also do the opposite. The Mitsubishis have sensors that will try to make the air blow where the people are. I think this would be better for cooling than heating. Mitsubishi also has a far distance setting which might help get air across the shop.

I put fans in the shop to help circulate the air though the mini splits seem to do an ok job at getting across 40' on their own.

I guess it depends upon how you define hot or cold. For me if it feels cool then that's too cold for a heat source. As I said I am used to propane heat and a wood stove. Propane furnaces blow around 140 degrees.

 

[My Old Tools]

I have a 36k MrCool. 30x40x12 shop. I would absolutely do it again. The first couple of days it ran it pulled gallons of moisture out of the shop. The inverter units should all dehumidify well since they can run lower speeds as needed.

 

[My Old Tools]

@dcg9381 What brand and size? I’ll be in the market soon enough here in DFW.
30x16 space.

Do yourself a favor, first double the roof insulation. It makes a huge difference in this area. I had an extra 8 inches strapped inside my roof. Then add AC. I used MrCool, did it myself, and I'm very happy with it. Mine is 30x40x12 and 36k was overkill.

 

[littleboss]

The problem with the minis, even those rated for -15 below is that the colder it gets capacity goes way down. So it has to run forever to produce the same amount of heat. Between that and all of the defrost cycles COP is now about as low as just running a regular elec heat strip

 

[shakenfake]

Do yourself a favor, first double the roof insulation. It makes a huge difference in this area. I had an extra 8 inches strapped inside my roof. Then add AC. I used MrCool, did it myself, and I'm very happy with it. Mine is 30x40x12 and 36k was overkill.

I will be insulating. I am going to do an attic space and have it drywalled and insulated. Just been lazy.

 

[pcmeiners]

The problem with the minis, even those rated for -15 below is that the colder it gets capacity goes way down.

That is a blanket statement which is not true. My Fujitsu low temperature 9k minisplits produce >%100 at -15 Fahrenheit. Yes many can not, especially the cheapest ones you can buy and it cost more to run at extreme cold conditions .

https://www.goodlifehvac.ca/images/Fujitsu_LZ_Series.pdf

"Between that and all of the defrost cycles COP is now about as low as just running a regular elec heat strip"

Do research before you make comments which are not true.

 

[kngelv]

The problem with the minis, even those rated for -15 below is that the colder it gets capacity goes way down. So it has to run forever to produce the same amount of heat. Between that and all of the defrost cycles COP is now about as low as just running a regular elec heat strip

You are 100% wrong on this.

That is a blanket statement which is not true. My Fujitsu low temperature 9k minisplits produce >%100 at -15 Fahrenheit. Yes many can not, especially the cheapest ones you can buy and it cost more to run at extreme cold conditions .

https://www.goodlifehvac.ca/images/Fujitsu_LZ_Series.pdf

You are 100% correct. I also have a Fujitsu that does the same.

James

 

[Dig Doug]

Not the garage

but
master bedroom

during summer when it’s 118 outside & 75 inside the house, we can crank down the master bedroom to low 60’s
and
then use the electric blanket

just because we can !


lol
2 ton pioneer

I need to add one to the boat side of the garage - someday

 

[rockcrawler]

X2 self-installed Pioneer 24K units in my 45x35x14 insulated shop in Texas and they cool and heat very well. Very happy with them.

 

[Merbesfield]

Do yourself a favor, first double the roof insulation. It makes a huge difference in this area. I had an extra 8 inches strapped inside my roof. Then add AC. I used MrCool, did it myself, and I'm very happy with it. Mine is 30x40x12 and 36k was overkill.

My Old Tools, I also have a red iron shop. 40’x80’x16’. I have the roll insulation that was installed at time of erecting. How did you “add” insulation after the fact? I see the straps, but is that enough to keep it from sagging?

 

[My Old Tools]

My Old Tools, I also have a red iron shop. 40’x80’x16’. I have the roll insulation that was installed at time of erecting. How did you “add” insulation after the fact? I see the straps, but is that enough to keep it from sagging?

|Yes, just the straps. My contractor did it at build time, but after everything else was done. This is my third shop and the first one with the added roof insulation. It really helps in Texas.

 

[Merbesfield]

|Yes, just the straps. My contractor did it at build time, but after everything else was done. This is my third shop and the first one with the added roof insulation. It really helps in Texas.

I will look into this. I’m sure the insulation they installed at erection is basic.

 

[AV8R4AA]

I have a 30X50 metal building 14 foot ceilings. I have a 4 ton Mr. Cool unit with 2 separate
head units on the wall of the long side. The shop is well insulated. A 4 ton unit for 1500 sq ft
Would calculate out as being too big. The most important lesson living in Texas is: There is no such thing as too big AC unit. Second thing I have learned is : NO MAN HAS EVER SAID: ”Honey, I built this shop too big” I’m very happy with my setup. I have zero worries about coldweather operactions. It just doesn’t stay cold that long here.

 

[Merbesfield]

I have a 30X50 metal building 14 foot ceilings. I have a 4 ton Mr. Cool unit with 2 separate
head units on the wall of the long side. The shop is well insulated. A 4 ton unit for 1500 sq ft
Would calculate out as being too big. The most important lesson living in Texas is: There is no such thing as too big AC unit. Second thing I have learned is : NO MAN HAS EVER SAID: ”Honey, I built this shop too big” I’m very happy with my setup. I have zero worries about coldweather operactions. It just doesn’t stay cold that long here.

I live in Georgia so it gets hot here but probably not as hot as Texas. My shop size will be the same as yours 30 x 50 x 14. When you say well insulated, what do you mean by well insulated?

 

[JackOfDiamonds]

Let me double-down on that. I have a 17 SEER unit in Texas. It will not heat worth a **** below 30 degrees. It cools great. You're in Idaho, so if heating is an issue (and it may be) pay attention. You CAN do units that are not heat efficient, but you need alternate heat. Don't be like me and try and live in the shop for a year when you hit a 100-year cold snap, the only thing colder than the shop will be your wife's icy stare.

I live in Idaho and have a Pioneer Quantum. It's actually not even one of the super-low-temperature ones -- the super low temperature ones use vapor injection -- but still it keeps my shop warm into the well below freezing temperatures. It builds up ice in the pan and even around the coils, but keeps working great the whole time. So I would say as long as you buy the right unit, heat is no problem. Even in Idaho.

Norway is a climate zone equivalent to Alaska, and over 70% of houses there use heat pumps.

 

[Ohmthis]

I really like mini split systems. I have in the past listed some of its shortcomings. Filtration and drawing air through the evaporator coil first. Here is a Mitsubishi 9kbtu hyper heat wall mount. I installed this about 9-10 years ago. About every couple of years I have to completely take it apart and clean everything. Coil, fan, frame, diverter blades, and then put it all back together. All said it’s about a 3-4 hour job. The black is mold. It draws air from the coil and I little bit of moisture. Over time it builds mold. Stay on cleaning the filter and make it a priority to clean the system.

 

[dcg9381]

@dcg9381 What brand and size? I’ll be in the market soon enough here in DFW.
30x16 space.

So I have a 2400 sqft shop. The "cheapest" option for me was to install 2 x 24K BTU units. At the time, it cost me about $2400 DYI all in.

I went with the bottom-tier Dakin 24k deals. They're great in the summer. Below 30 in the winter, they are near worthless. But for $300, I installed ductless propane heat and can heat the shop via a 100 lb propane tank.

 

[Jetsurgeon]

Had a Mr Cool 18k in my old 28x24 shop in Savannah. Worked great all year.

Not sure if I'm going to put one in my new garage or not. Let's get through a summer and see how it feels out there first.

OK, so a 36K in Orlando should be OK then for a 24x50x9.....