Multizone Mini Split?

[Bob B]

I am planning to install mini splits in my home and will need 4 indoor units. I prefer the mini splits because of the increased efficiency as well as the ability to only cool areas I'm utilizing.
I currently have a high efficiency gas whole house furnace for heating, but am utilizing window units for cooling. I don't want to have to cool the entire house.
2 of the indoor units will need to be ceiling cassettes (or slim duct units) and 2 of them wall units. I am thinking about using 2 ... 2 zone .... mini splits instead of going with 4 individual units. 3 of the indoor units will be 9K and 1 12K.
Surprisingly, using individual units may actually be less money .... especially for the ones where I can use a wall mount indoor unit. Doing this for the best price is a major consideration.

I have seen a few posts from people saying it is best just to stick with single zone systems .... I was thinking doing 2 would be somewhat of a compromise and have the benefit of only needing to run 2 electric circuits to outdoor units.

Feedback I'm looking for:
1. Feedback from anyone who was using a 2 zone unit and later decided it was a bad idea.
2. Can anyone recommend a 2 zone unit they like?
2. Has anyone used one of the slim ducted mini split units?
3. Has anyone purchased from this place? https://minisplitsforless.com/colle...split-air-conditioners?variant=39625475522752

 

[740GLE]

Look at SEER values of single head units vs multi heads, it appears single head units will win hands down vs multi head.

Down side of running 4 separate units is wiring/disconnects then also potential for 4 different refrigerant leaks.

Personally we went with a 3 head unit (only using 2 heads), 30k BTU Mitsu hyper heat, for ease of install, all on one side of the house.

So far so good but we’ve only had it for a couple weeks and weathers been seasonably cool.

 

[ruralsolar]

1. Not using, but not long ago watched a youtube video about multi-zone units. Didn't realize that if the outdoor unit is running refrigerant is running to all the indoor units irregardless if they're calling for anything or not. It's also possible to end up with a split demand "issue" where one inside units wants cooling while the other wants heat, easily mitigated with ensuring settings.
2. Went with hydronic based setup so no.
3. My brother has, he likes them, easier to hide than a whole sized air handler
4. Nope, have looked at this before though: https://www.acwholesalers.com/

 

[Ampster]

I installed a 3 zone LG mini split which I purchased from ecomfort.com

 

[740GLE]

1. Not using, but not long ago watched a youtube video about multi-zone units. Didn't realize that if the outdoor unit is running refrigerant is running to all the indoor units irregardless if they're calling for anything or not. It's also possible to end up with a split demand "issue" where one inside units wants cooling while the other wants heat, easily mitigated with ensuring settings.
2. Went with hydronic based setup so no.
3. My brother has, he likes them, easier to hide than a whole sized air handler
4. Nope, have looked at this before though: https://www.acwholesalers.com/

I think it’s more of the direction of the pump, all heat or all cool.

There are control valves on the outdoor unit to control flow to which units needs it.

 

[Bob B]

I installed a 3 zone LG mini split which I purchased from ecomfort.com

How long have you had it? Are you happy with it?
Can I ask where you bought it? DIY install? Why LG .... Do they do multizones better?

 

[Ampster]

Installed it DIY In November 2021 so it has worked well heating for two winters. I am very happy with it. I use very little cooling. I picked LG because of their reputation and the thin wall units, plus they had a ceiling cassette.
Purchased from comfort.com and some parts from hvacdirect.com.

 

[hwy17]

The best benefit of the doubt that I can give to multi zones is that maybe if both heads are very evenly loaded like they are both heating similar size bedrooms with similar heat loading then I believe it is possible for them to be efficient, and that's how they get away with good data in the certification process.

If one head is a tiny bedroom and the other is a big living room full of windows, they're terrible.

I will avoid the problem entirely and never buy another multi zone after my 27k 4th gen mrcool diy with 18/9/9 heads.

 

[Ampster]

I will avoid the problem entirely and never buy another multi zone after my 27k 4th gen mrcool diy with 18/9/9 heads.

Was your issue MrCool or the fact that you could only get 27k out of a 27k system?

 

[hwy17]

Was your issue MrCool or the fact that you could only get 27k out of a 27k system?

I'll forgive that question cause I'm new around here, lol.

No my problem is mainly with two modes:

1. 27k running 9k bedroom only - poor efficiency.

2. 27k running 9k bedroom (light loaded) and 18k living room (heavy loaded), bedroom loses control and overheats because living room is calling for such high output.

And honorable mention to:

3. I can't believe it but I do want to heat and cool different zones at the same time.

 

[Shimmy]

Really it comes down to how you use them. A multi-head can only do ~25% minimum output, so if you are only cooling one of two rooms and it isn't especially hot out it won't work well.

 

[Bob in Tucson]

I have seen a few posts from people saying it is best just to stick with single zone systems ....

As others have said, one inside unit paired to one outside unit has the potential for the highest efficiency; I say potential because SEER ratings vary considerably across models.

Despite the cost in efficiency, I went with a three-zone Mitsubishi because I didn't want condensers everywhere on my small lot. It's feeding a 9k slim duct, a 6k wall unit in a bedroom, and a 15k floor unit in the living room. I just started using it but so far so good. No issues with running heads separately or simultaneously.

You asked about the slim duct and it's nice -- super quiet. It's connected to a small run of ducts we designed to feed two rooms.

Like others, I purchased it from eComfort.com and that was a good experience. I called then with questions and they were helpful; when they didn't know the answer to one, they connected me with an engineer from Mitsubishi.

Feedback I'm looking for:
1. Feedback from anyone who was using a 2 zone unit and later decided it was a bad idea.
2. Can anyone recommend a 2 zone unit they like?
2. Has anyone used one of the slim ducted mini split units?
3. Has anyone purchased from this place? https://minisplitsforless.com/colle...split-air-conditioners?variant=39625475522752

 

[tomy2]

whatever you do, don't buy a senville, they suck.

 

[Bob B]

whatever you do, don't buy a senville, they suck.

Could you give us more information about what brought you to that conclusion?

 

[timselectric]

Could you give us more information about what brought you to that conclusion?

Red marks around the neck. lol

 

[MarkSolar]

I just installed two 48k Mr cool units, each with 4 heads. It was all installed in an old barn that's been converted to a wedding venue. So the purpose of multiple heads was to carry the cooling to the far end of the barn. Manual gave a minimum btu demand for proper operation, I think it was 18k. I thought it was all pretty well engineered, bought it from Ingrams. So quiet you can't hear it.

 

[tomy2]

Could you give us more information about what brought you to that conclusion?

i have two from senville, both came low on refrigerant and with faulty parts. it takes a month to get the part that they swear will fix it, then you get to spend three hours installing the part, and it still doesn't work . then another month to get the next part. four months later it finally works, and you spent twenty hours of free labor fixing their defects. need i say more

 

[rcrracer]

https://ashp.neep.org/#!/product_list/ There appear to be 2861 single zone non-ducted wall mounted listed on this website. 1217 multizone non-ducted listed. Then there is all the other configurations.

 

[JohnTupper]

I am planning to install mini splits in my home and will need 4 indoor units. I prefer the mini splits because of the increased efficiency as well as the ability to only cool areas I'm utilizing.
I currently have a high efficiency gas whole house furnace for heating, but am utilizing window units for cooling. I don't want to have to cool the entire house.
2 of the indoor units will need to be ceiling cassettes (or slim duct units) and 2 of them wall units. I am thinking about using 2 ... 2 zone .... mini splits instead of going with 4 individual units. 3 of the indoor units will be 9K and 1 12K.
Surprisingly, using individual units may actually be less money .... especially for the ones where I can use a wall mount indoor unit. Doing this for the best price is a major consideration.

I have seen a few posts from people saying it is best just to stick with single zone systems .... I was thinking doing 2 would be somewhat of a compromise and have the benefit of only needing to run 2 electric circuits to outdoor units.

Feedback I'm looking for:
1. Feedback from anyone who was using a 2 zone unit and later decided it was a bad idea.
2. Can anyone recommend a 2 zone unit they like?
2. Has anyone used one of the slim ducted mini split units?
3. Has anyone purchased from this place? https://minisplitsforless.com/colle...split-air-conditioners?variant=39625475522752

I ended up installing 4 single zone systems because multi head systems don't come in the 38 seer ?

 

[DrZ123]

I ended up installing 4 single zone systems because multi head systems don't come in the 38 seer ?

I'm assuming not DIY units? I'd love to hear from someone who has say a 22 SEER unit and a 38 SEER and see how much of a power draw difference there actually is?