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Mitsubishi Mini Split 42k Hyper Heat. My opinions on my setup.

drps10

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Joined
Jun 25, 2023
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106
Location
ohio
With these cold temps everyone is having, would post on here too. If anyone has questions or considering it, ask all the questions.

1300 sq ft upstairs, 750 sq ft finished walkout basement, Northern Ohio. Single story with a walkout basement. New windows, semi ok attic insulation and shitty construction accounts for air leak I can't fix yet.

4 rooms have indoor units (6k,6k, 12k, 18k) with a branch box in the attic. Turned it on for the first time Jan '23. This is the coldest we have encounter with this setup and its doing very well. Was down to 0*F with a wind chill of -11*F. Todays High will be 13*F and a low of 4*F. We have still installed but not on for most of the rooms electric baseboard heaters on 240v. I bought the system for A/C, because we don't have central a/c I wanted something and was tired of window units. I decided to go with Mitsubishi because it would heat down to -13*F with a COF of 1 still.

The highest I saw on my Emporia was 7kw pulled for a few minutes. As I typed this, I am looking at the data and it appears those high pull are after a defrost mode (no way to officially tell, but seems to be that). I would imagine that it is getting the house back up to temp. On an average temperature day of 35*, it will pull 1.8kw/hr.

We have the 18k upstairs heating living room, kitchen and shooting down the hall. 6k in 2 bedrooms and one bed with no heat (baseboards but I don't have it on). 12k in the finished basement and 2 bedrooms down there with baseboards turned on. IDU for living areas are set to 69 and bedrooms all set to 67.

As far as A/C, it uses less energy than my 2 windows units that I ran. For heat, I didn't have the Emporia long enough to get a gauge on energy use to heat the house solely on baseboards.

I know I don't have much info for this post, but figured I would make a thread so people can discuss Mitsubishi Heat Pumps if need be.

I did the entire install myself except for r410a install.

I do have this amazing website that I came across that give real number for COF and energy use that is privately done (not manufacture numbers). You can search all heat pumps. https://ashp.neep.org/#!/
IMG_1435.PNGIMG_1434.PNG
 
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1 story with walkout basement?
~2ksqft?
when was it built?

Around freezing it sounds like ~40kwh/day to heat, how's it doing with the near zero per day (looks like 4kwh/hr, or 96kwh/day)?
 
I think I’m around 2100 sq ft of conditioned space. Yesterday I used 81kw to heat the house. The high was 13 and got down to 0. The lowest the system will pull is 1.2kw just because how big the ODU is. 1.8kw is the going avg to heat the house any outside temp above 35*f. When I get to around 30* it’s around 2kw. 20* around 2.5kw. 10* 3.5kw. 0* seemed to pull around 4.5kw plus or minus .5kw.

Currently 10*f right now, 3.8kw pulling 16amps. output on the 2 units currently running 115*F
 
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just happen to catch a defrost cycle. Took longer to get back up to heat than to defrost. Must not be much frost on it.


defrost cycle.jpg
 
Can't wait to check out that website, thanks for sharing it. We are off grid in Alaska powered by solar and just installed a one ton Mitsubishi Hyper Heat this last fall (everything installed except the line set). So we'll have it connected in the Spring fingers crossed. Very interested in how much power it's going to require.

Our numbers for our 1200 square foot cabin are:

Floor insulation: R-53.7
Wall/door insulation: R-24.0
Ceiling: R-59.4
Windows: U-0.26
Window SHGC: .21
Window to Wall Ratio: 12.3%
Air leakage: 1.05 Air Changes Per Hour at 50 Pascals (blower door tested)
Heating Design Load: 11,964 BTU/hr

The best we can hope for from our solar is about 20KW on the darkest day and that's if the sun is out. But once we get a diesel DC generator, we'll at least have the option to burn diesel or fire up the wood stove to heat on those days. Outside of December our solar power generation goes up pretty quickly so I think the heat pump should mostly be powered by solar. Hopefully all the extra insulation we put in this summer does the trick..
 
Which unit are you installing? Mine is a 3.5 ton unit. It pulls a big load to heat a poor construction home. Your 1 ton numbers will be great for that unit. Is it an open concept or a bunch of rooms?
 
The units are MSZ-FS12NA & MUZ-FS12NA I think. Just a wide open space right now, we haven't put up any interior walls yet. But we're only going to have one small room for the bathroom and the rest will stay wide open.

I guess we were kind of lucky that everything is so slow going here because although we've been building for five years, we still didn't have our walls closed up until this past summer so we were able to add more insulation before that. It definitely made a difference with the amount of heat we burn in the wood stove and we can now hear an echo in the cabin. Even if we use wood in December, it should cut our wood usage by 90% or more. We used to have to burn wood in July at times believe it or not.

Definitely interested in the real world numbers when we get the line set installed.
 
With these cold temps everyone is having, would post on here too. If anyone has questions or considering it, ask all the questions.

1300 sq ft upstairs, 750 sq ft finished walkout basement, Northern Ohio. Single story with a walkout basement. New windows, semi ok attic insulation and shitty construction accounts for air leak I can't fix yet.

4 rooms have indoor units (6k,6k, 12k, 18k) with a branch box in the attic. Turned it on for the first time Jan '23. This is the coldest we have encounter with this setup and its doing very well. Was down to 0*F with a wind chill of -11*F. Todays High will be 13*F and a low of 4*F. We have still installed but not on for most of the rooms electric baseboard heaters on 240v. I bought the system for A/C, because we don't have central a/c I wanted something and was tired of window units. I decided to go with Mitsubishi because it would heat down to -13*F with a COF of 1 still.

The highest I saw on my Emporia was 7kw pulled for a few minutes. As I typed this, I am looking at the data and it appears those high pull are after a defrost mode (no way to officially tell, but seems to be that). I would imagine that it is getting the house back up to temp. On an average temperature day of 35*, it will pull 1.8kw/hr.

We have the 18k upstairs heating living room, kitchen and shooting down the hall. 6k in 2 bedrooms and one bed with no heat (baseboards but I don't have it on). 12k in the finished basement and 2 bedrooms down there with baseboards turned on. IDU for living areas are set to 69 and bedrooms all set to 67.

As far as A/C, it uses less energy than my 2 windows units that I ran. For heat, I didn't have the Emporia long enough to get a gauge on energy use to heat the house solely on baseboards.

I know I don't have much info for this post, but figured I would make a thread so people can discuss Mitsubishi Heat Pumps if need be.

I did the entire install myself except for r410a install.

I do have this amazing website that I came across that give real number for COF and energy use that is privately done (not manufacture numbers). You can search all heat pumps. https://ashp.neep.org/#!/
View attachment 189113View attachment 189114

How did you get to that KW calculator? Is that from the NEEP website or did you have to download an app?

Or maybe that's not available for my pump?

 
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