After a month of planning I finally installed the Mr. Cool 12k BTU heat pump. It took me 1.5 days to do it all and it was very straight forward. It's blowing nice cold air right now. My brother-in-law talked me down from the 18k unit because he runs a 12k and it does perfect. Not only was it cheaper to buy, but being a 120v unit, everything was cheaper- single 20 amp breaker, 12 gauge wire, 10 gauge pigtail, etc. We'll see how it hold up on the hottest days but it's got to be better nothing. All in, about $2300.
Finally installed the Mr. Cool 12k heat pump.
- Thread starter zimm17
- Start date
daveindenver
Member
- Joined
- May 12, 2018
- Messages
- 22
Nice, looks good. Is that the DIY one? Did it come with a 25' line set? Doesn't look like you had to coil much. What do you mean by 10 gauge pigtail? What were the larger costs besides the unit itself?
housewolf
Well-known member
You’re going to love conditioned air in your shop/garage. Back in April, I put an 18K Daiken in my shop. Yesterday it was 102* here with humidity around 80%. I could only keep it at 83 inside the shop in the heat of the day but humidity was as low as 24%. It was very comfortable in there. I imagine if I insulated my roll up door I could do a little better but I’m fine with it like it is as long as I don’t have to work too close to the door
Yes the DIY with 25' line set. I used a 25' extension cord to mock up where the line set would go and placed the head on the wall so I'd have a foot or 2 extra. That worked well. I'd rather one extra loop than coming up short! The pigtail, or appliance whip, goes from the disconnect box to the outdoor unit. Home Depot only had 10 gauge as the smallest, but it works just fine. Larger costs:
Line set covers x3, 90's, and end fittings- about $200.
3 spools of 12 gauge THHN wire (hot, neutral, ground)
25' flexible conduit and fittings, 90 degree junction box, disconnect box, conduit fittings
Plastic pad for outdoor unit plus 2 bags of paver base crushed stone
Circuit breaker for panel
I ran 12 gauge Romex wire from breaker to the junction box on the outside wall, then THHN wire through conduit to the disconnect box then the whip to the outdoor unit. I could have used rigid conduit, but I had to dip under the white privacy fence, so I kept it all flex.
I have insulated doors, and the ceiling and 2walls are insulated. The outside wall where the head is mounted isn't insulated, but doesn't get direct sun. Hopefully it'll keep it cool on a hot day. The weather has been great this week so not much of a test for it. But it took the garage from 81 to 75 (the set point) in a couple of hours with much less humidity. I have it on 77 right now, and I can always bump it down if I'll be out there on a project.
housewolf
Well-known member
I’m sure it will be fine. I neglected to mention in my previous post, I moved two hot vehicles (one at a time) into my shop that day and the door stayed open a lot more than a little. It was closed up all day yesterday and never got above 78 with the set point on 80* (my unit & thermometer aren’t near each other)
mike93lx
ALLIANCE MEMBER
Looks good. Where did you run the condensate line?
It pokes out the bottom of the first 90 elbow so it’s a straight shot down from the unit.
mike93lx
ALLIANCE MEMBER
Ah I think I can see it.
Letting it drip from that height is going to cause some splashing, no? And put the water right up against the house
kinggsxr
Well-known member
What is the square footage of your garage? I have roughly 400 sq. ft. and am being told to go with at least a 18k unit if not 24k. Based on the calculation I should be ok with a 12k but I thought about bumping up to the 18k since my garage faces west.
mike93lx
ALLIANCE MEMBER
24k is absurd for 400 sq ft. Is it uninsulated and incredibly leaky? Who is telling you that?
My garage is 19x24 with 12 foot ceilings. But has a bedroom over the top so the ceiling is insulated and shares 2 walls with the house so those are insulated too. Insulated doors that only get the morning sun (facing east). The 12k has no issues keeping it at my set temp, which for now what only been 77, which feels cool when the humidity is knocked down. I'm also not constantly parking a hot car in the garage- my Jeep is my toy and doesn't get driven much and the other car is a Tesla, which I'm assuming doesn't bring a lot of heat into the garage.
kinggsxr
Well-known member
I got 2 quotes recently from HVAC installers and that was their recommendation since there was not a price difference between the 18k and 24k. My garage is about 90% insulated just a small section of the ceiling towards the front is (presumably) uninsulated.
Mine is 20x22x11 and also has a bedroom above and I recently had insulation blown into the exterior wall and I also do not park any vehicles in the garage. I may reconsider the 12k now but still leaning towards the 18k since facing west it gets pretty toasty in the evening.
I was leaning towards the 18k but my brother has a 12k in his garage and keeps it at 72 (no cars, just motorcycles). Once I saw the mr. cool 12k was much cheaper, and only 120volts- which made the wiring easier and cheaper too, I went that route. These mini-splits are supposed to run constantly (well the compressor cycles as needed) , nto cycle on and off like a whole house A/C- so if it's oversized, it might not run enough.
mike93lx
ALLIANCE MEMBER
Load calcs are expensive when done by a pro and as are call backs for poor cooling performance, so upsizing is easy.
For a well insulated space, I bet 12k gets it done.
How invasive and expensive was it to blow insulation into the outside wall? I'm considering having that done as well as the wall cavities are currently empty and I might to keep the heat in this winter.
kinggsxr
Well-known member
It was not bad at all. They drilled 3 in diameter holes in between the studs and hung plastic sheets around the work area then blow in the insulation. The whole thing took just a couple hours. They clean up after and patch the hole with a wooden plug that you can spackle and paint over.
In case you are in the DMV area, I had Comfenergy do the install and highly recommend them. They were very reasonably priced and did a good job. I had gotten quotes for spray-in foam that were north of $3k just for 1 wall and others were charging a minimum price just to come out and do a job, regardless of the amount of area.
pcmeiners
Well-known member
"24k is absurd for 400 sq ft. Is it uninsulated and incredibly leaky? Who is telling you that?"
Fully agree, maybe 24k with the garage door (and any windows) fully open.
Presently have a 1080sqft garage and my attached home (temporarily) being cooled by a 12k Fujitsu minisplit .In the winter no issue heating at 7 degrees.
OPs should look through previously posted threads. All the info given in this one, and more, has been posted in other threads.
Fully agree, maybe 24k with the garage door (and any windows) fully open.
Presently have a 1080sqft garage and my attached home (temporarily) being cooled by a 12k Fujitsu minisplit .In the winter no issue heating at 7 degrees.
OPs should look through previously posted threads. All the info given in this one, and more, has been posted in other threads.
bluedog225
Well-known member
The 25’ extension cord was smart. Stealing that idea.
MadScientist3019
Active member
Teslas add a fair amount of heat when charging, they run the cooling system to keep the battery cool and the battery itself is warm after having driven. Have 2 in my garage and notice the heat for sure, especially when charging at 9kw for each. I also think the amount being quoted is quite high. I'm just finishing my shop that's 40x60 with 13 ft side walls and I did a manual J for it and found that I can get away with about 20k btu for heating and only about 10k btu for cooling but part of that is my 2x6 walls with full insulation and another 1 inch of full foam exterior under my siding and I also did 2 inches of foam down 24 inches around the perimeter to keep my slab from being a huge heat sink to outside. Going to blow in R38 in the ceiling with cellulose too on top of my 5/8 drywall. There are manual J calculators for free online to tell you what your loads should look like, like this one: https://www.loadcalc.net/load.php
Well it's one of the hottest days we've had so far the summer- 94 outside, 98 heat index. Wife just parked her hot Tesla 3 in the garage and it's charging. Mr. Cool is still maintaining the set 77 degrees. I'm happy. Now to see what winter brings.
Highbeam
Well-known member
I have a 24k DIY in my home self installed. The inside unit will be moving air constantly but the outdoor unit is far less predictable. Sometimes the fan stops, sometimes the compressor cycles while th fan stays running, the fan speed changes, the compressor speed changes or cycles. I just let it do its thing and enjoy the conditioned air.
desmopower
Member
- Joined
- Jun 10, 2010
- Messages
- 14
I agree with others that sounds crazy. I have an 18k for a 700sqft garage with 1 wall uninsulated and it keeps up summer and winter when there is snow on the ground.
I'd check a few websites and average the result, and do your own manualj calc, but you may be in the 12k or 15k territory.
rixtrix1
Well-known member
Running on only 12k in a garage your size is great, bur you are in a much better climate than me. Install looks really clean! I have a 12k, 240V A/C with 12K resistance heat in our 17x19 fully insulated atached garage and can keep it at most any temp I desire in the hot Phoenix summer where winters have a couple of months of 30* nights.
I just installed a 24k DIY mini split in my new 24x32x10 shop with 8/12 pitch roof (19'6" peak with no ceiling insulation yet )and it had no problem keeping 80 degrees at 20% humidity when it was 118 outside today at 5PM. I turned it down on a 110* day and got it down to 70* which was uncomfortable! I was able to use the 3 meter line unit that came with the package. With a line cover kit total price was $1250. Not near the SEER of a Gen 4 Mr. Cool but only half the price and I did it all myself. It's easily cool enough to start insulating the ceiling with R 30 batts. I have R15 Rockwool in the walls and carriage doors already.
I just installed a 24k DIY mini split in my new 24x32x10 shop with 8/12 pitch roof (19'6" peak with no ceiling insulation yet )and it had no problem keeping 80 degrees at 20% humidity when it was 118 outside today at 5PM. I turned it down on a 110* day and got it down to 70* which was uncomfortable! I was able to use the 3 meter line unit that came with the package. With a line cover kit total price was $1250. Not near the SEER of a Gen 4 Mr. Cool but only half the price and I did it all myself. It's easily cool enough to start insulating the ceiling with R 30 batts. I have R15 Rockwool in the walls and carriage doors already.