Choosing the right brand for a mini-split

[sportbikerider78]

I have a window unit stuck in a sliding door. It's ghetto as all hell but i have no neighbors and it keeps me cool.

 

[fbelec]

I have a window unit stuck in a sliding door. It's ghetto as all hell but i have no neighbors and it keeps me cool.

good for you thinking like that. do what you gotta. did that in a rented camper brutally hot and humid and the trailer had no ac. called a friend said bring down the extra ac i had and a roll of plastic and of course more beer

 

[sportbikerider78]

It is running. I am so happy!!

This is a great day to get a system running. 92F and crazy humid.
Been running for 2 hrs and the temps have house wide have gone frim 82F to 76F on a very hot day. I'd say we got the right unit.
I still have to clean up the way the linesets coming out of the house look, and get the covers on, but first I am going to run the hell out of it an make sure the condensation is running down the lines properly.

The head units are on full blast (speed 4) and you can hear them...they sound like a normal HVAC system coming on. On speed 1 and 2 you can't even hear them.

The condenser is 10 feet under my deck from where I am typing and it is completely silent to me. While standing above it on the deck, you can hear the purr of a condenser, but man, the locusts are louder than the condenser. Very happy!
Total bill was a little more than I was quoted, but only by $100. Total was $700.

 

[begreen]

Congratulations!! I think you're going to love this unit. It wouldn't surprise me if it also changed your burning habits. It's more efficient, easier and much cleaner to run the heat pump during shoulder season. Now that we are buying wood we have found out it's also cheaper!

 

[sportbikerider78]

Congratulations!! I think you're going to love this unit. It wouldn't surprise me if it also changed your burning habits. It's more efficient, easier and much cleaner to run the heat pump during shoulder season. Now that we are buying wood it's also cheaper!

Thanks man! I think you are very right!

In 2 hrs it dropped the RH from 65% to 49%. Can't wait till tomorrow morning when the system has stabilized at about 72F.

I know it is ridiculous, but I'm genuinely giddy like a kid on Christmas. So much planing, hard work and time taken to get this going.

 

[Tegbert]

My 42kBTU unit is on its way. Shipped yesterday.

I will have 15k head, 15k head and a 12k head unit.

I have a friend that is an electrician and he will be coming to home depot with me to buy everything I need to install 2 20A fuses, run the cable inside, run outside to my disconnect, wire the disconnect and then to the unit.

Good times. 90F at my house yesterday but this next week or so is a nice temp to get things done.

I have a question about this. Why did you match the outdoor unit with the indoor unit total btu? I was always under the impression that you could take the indoor units total to 150% of the outdoor.

I may have missed it but what size is your house and where are the head units at?


Lopi Rockport
Blaze King Ashford 25

 

[sportbikerider78]

I have a question about this. Why did you match the outdoor unit with the indoor unit total btu? I was always under the impression that you could take the indoor units total to 150% of the outdoor.

I may have missed it but what size is your house and where are the head units at?

Lopi Rockport
Blaze King Ashford 25

I went through this with the Mitsubishi tech. Here is the explanation he gave me.
You can do that, but you will only get the amount of cooling at the head units the condenser is sized for. With matched units on a day like today where it is 92F outside, I can run the entire system full bore and get 42k of cooling.

I actually bought a 2.5T/30kBTU unit with the intention of running 42k of head units. The cost to upsize to a 42k condenser was marginal, so I sprung for it. The issue would be on a warm day like today, when the head units are asking for more cooling then the condenser can provide. I think you are right, you can exceed the head unit rating by a certain amount, but I had a very hard time figuring out what amount that was and there was no point in risking it.

My house is a long ranch. 1900sqft. 3 bedroom. 2.5 bath with very high ceilings 9-20'. The head units are in family room, kitchen area and master bedroom, where my office is. The other 2 bedrooms are off the family room and will have a unit, basically blowing cold air at their open doors. Very easy to put a fan in their rooms to help move air.

Another reason I upsized the unit, was because I thought maybe I would add an additional head to the basement for heat in the winter and dehumidifying in the summer. That unit would have been rather small and occasionally used...I was thinking 9kBTU.

(BTW...that 2.5T unit is in the box and for sale for what I paid..about 50% off list...PM me if interested)

 

[sportbikerider78]

Google maps isn't what it used to be...but this is the home and layout...very roughly.

Red dots indicate head units.

 

[Tegbert]

I look forward to hearing your results with this. Especially in the two other bedrooms on how well they do. Although I suspect just fine since the master and room next to it both look like they point that direction.

My house is also 1900 sqft but short ceilings just under or at 8’. This has caused me some headaches on what and how to place the heads and where. Not sure I or my wife would like to see the head units almost at eye level but dealing with duct work for the ducted versions doesn’t seem to appealing either as far as matching size of duct work to what the static pressure of the blower is and what not.

Decisions decisions.


Lopi Rockport
Blaze King Ashford 25

 

[sportbikerider78]

I look forward to hearing your results with this. Especially in the two other bedrooms on how well they do. Although I suspect just fine since the master and room next to it both look like they point that direction.

My house is also 1900 sqft but short ceilings just under or at 8’. This has caused me some headaches on what and how to place the heads and where. Not sure I or my wife would like to see the head units almost at eye level but dealing with duct work for the ducted versions doesn’t seem to appealing either as far as matching size of duct work to what the static pressure of the blower is and what not.

Decisions decisions.


Lopi Rockport
Blaze King Ashford 25

I believe you have to leave the units about 3" of clearance above them, as that is the intake. So..not quite eye level, but I know what you mean.

I think the big thing is just getting the humidity down. Even 75F really is ok, if it feels dry. A fan in the room does quite a bit then.

 

[peakbagger]

Yup, life will be good. Now you need to figure out all the icons on the remote. I tend to run humidity control on really damp days and the temps drift down anyhow.

Even though they are primarily a cooling unit for you, you will be impressed when you need little heat in shoulder season.

 

[sportbikerider78]

Yup, life will be good. Now you need to figure out all the icons on the remote. I tend to run humidity control on really damp days and the temps drift down anyhow.

Even though they are primarily a cooling unit for you, you will be impressed when you need little heat in shoulder season.

I have had a Looooonnngggg time to figure out the remote. LOL

I'm setting the temp at 70F, the fan on auto and telling the wifey not to touch it.

Now, I'm thinking about the home that i'll be building out in the Albany, NY area when we move there in the next 6 months or so....I'd love to have one of these units in a new construction. That would be pretty awesome.
Now i'm thinking about all the different heating options that I'd need for the coldest part of the winter. Wood obviously, is my go-to. But what would complement this system well for heat when it is <30F?

I'm just daydreaming about the next house...my current one has a new oil boiler. All set there.

 

[Ashful]

I have had a Looooonnngggg time to figure out the remote. LOL

I'm setting the temp at 70F, the fan on auto and telling the wifey not to touch it.

Now, I'm thinking about the home that i'll be building out in the Albany, NY area when we move there in the next 6 months or so....I'd love to have one of these units in a new construction. That would be pretty awesome.
Now i'm thinking about all the different heating options that I'd need for the coldest part of the winter. Wood obviously, is my go-to. But what would complement this system well for heat when it is <30F?

I'm just daydreaming about the next house...my current one has a new oil boiler. All set there.

Congrats, sports. I remember when I got central AC finally installed in my first house, after 35 years of suffering these mid-Atlantic summers, like you it was a minisplit.

Last week, I spoke to one of the system experts at our largest local plumbing and HVAC installation company, about wanting to install a heat pump water heater. He took at look at my setup, and said he wouldn't change a darn thing. He cited the recovery time remorse many have with HPWH's, and how efficient my boiler and boilermate system are.

I'm still going to do the HPWH, mostly because the boiler running all summer makes our basement rec. room too warm for the kids, but my point is that sometimes it's hard to beat the horsepower of a boiler. You know I have quite a heat load, here, and that little boiler in the basement has no trouble carrying 100% of it in the coldest of weather.

I'm a big fan of having a boiler with hot water for heat, and a separate AC system for cooling, but this has a high up-front cost. All of my neighbors went with ground source heat pumps, as their sole heating, in much newer houses. Of course, they each seem to experience a failure once or twice each year on much newer hardware, whereas we're always warm with our 30 year old boiler.

 

[fbelec]

you did the right thing by matching the units to the compressor. and you find that out on a screaming hot day and you have a load of people over and the kids open and closing the door. if it were small your temp would climb and everybody would be uncomfy

 

[Soundchasm]

The great thing here is that you did the right thing for the structure. I always try to look at the "long" side of things. It cracks me up to no end that in 200 years, somebody is going to be cursing me for the oaks that I've planted. In the short-term, somebody is going to be THANKING you for your foresight with these mini-splits. Good job! Even if you don't benefit directly from this, your experience will help you in the future and be a BIG help to future residents. You gave your neighbors a gift and they don't even know it!! ;-)

 

[peakbagger]

Once you get the humidity out of the air, 70 degrees is going to feel appropriate for hanging meat . I like it cool and usually have mine set at 75 F.

I heat my small fairly tight house down to 30 F with a one ton minisplit. If the sun is out, I can go down to 20 F. Anything lower and its pushing it.

I would be tempted to put in one of the picture frame or ceiling cassette units in new construction. I dont think they move the air around as well but they are visually less intrusive.

 

[maple1]

Picture frame? Is that something new?

 

[Ashful]

Once you get the humidity out of the air, 70 degrees is going to feel appropriate for hanging meat . I like it cool and usually have mine set at 75 F.

I heat my small fairly tight house down to 30 F with a one ton minisplit. If the sun is out, I can go down to 20 F. Anything lower and its pushing it.

I would be tempted to put in one of the picture frame or ceiling cassette units in new construction. I dont think they move the air around as well but they are visually less intrusive.

Ditto, on all three of your points. My barn mini split fails to keep up heat at anything below 15F, and it sucks an enormous amount of energy just trying. It’s great above 25F, though. We usually see two or three weeks between single digits and teens each year, and often four or six nights sub-zero, I just eat the cost those few days each year.

On cooling, since ours is going 24/7 from May thru September, we have basically no indoor humidity. The house feels comfortable around 75 - 76, if you’re wearing shorts and tee shirt. That’s good for sitting and watching the TV, but not for working hard. I turn the shop down to 70F, when I’m working out there.

 

[Ashful]

Picture frame? Is that something new?

There are several types of mini split indoor units that can be concealed within walls or ceilings. All you see is a register, which can look like traditional AC. These are for new construction, they’d be a difficult retrofit.

Of course, I’d probably not choose a minisplit for new construction, their primary application is retrofit.

 

[maple1]

There are several types of mini split indoor units that can be concealed within walls or ceilings. All you see is a register, which can look like traditional AC. These are for new construction, they’d be a difficult retrofit.

Of course, I’d probably not choose a minisplit for new construction, their primary application is retrofit.

Yes, I had seen some. But not remembering something resembling a picture frame. The ceiling cassettes had me quite interested until I found they won't fit between 16" joists. You need 24" OC. Or all the ones I saw at least - I have a spot in a first floor ceiling where one would do very well, if it would fit. I will have to check them all out again to see what's new in the last couple years, if anything. I think I almost have wifey convinced, she has been dead against them from the get go for some weird kinda reason - but she did ask last month about how much they cost. We don't have very many spots where a typical high up wall mount would fit very good, it seems.

I would definitely consider a minisplit for new construction, almost seems a no-brainer in my mind. It's being done a lot around here now. We don't have NG though - that might make a difference.

 

[Ashful]

Yes, I had seen some. But not remembering something resembling a picture frame. The ceiling cassettes had me quite interested until I found they won't fit between 16" joists. You need 24" OC. Or all the ones I saw at least - I have a spot in a first floor ceiling where one would do very well, if it would fit. I will have to check them all out again to see what's new in the last couple years, if anything. I think I almost have wifey convinced, she has been dead against them from the get go for some weird kinda reason - but she did ask last month about how much they cost. We don't have very many spots where a typical high up wall mount would fit very good, it seems.

I would definitely consider a minisplit for new construction, almost seems a no-brainer in my mind. It's being done a lot around here now. We don't have NG though - that might make a difference.

It’s hard to argue with the economics of a ducted system, for new construction. This is why we mostly see minisplits as retrofits, around here.

As I understand it, the biggest issue with retrofitting the ceiling units into existing construction is drain line routing. They’re apparently fairly sensitive to drain line slope. Also, at least back when I was shopping them, the Mitsubishi ceiling units could not do heating, only cooling.

 

[peakbagger]

I have not had an experience with either one of them, either ceiling cassette or picture frame but have seen glossy pictures of them The picture frame has artwork in the middle surrounded by louvers that look like picture frame. With both of them I expect the performance is impacted.

 

[fbelec]

i've wired the ceiling and wall type i think the ceiling cass is way more visible and normally mounted in the center of the room that screws up installing a ceiling fan..i wired a apartment with the ceiling cass. 2 for heat and a.c. takes less power than your everyday duct style. don't forget that the conv. duct style has very high seer ratings now 21 22 and higher. if doing a new construction central heat there is dual fuel furnaces. very efficient

 

[maple1]

Did some quick googling and I only found LG 'picture frame' units. When we take the plunge it will either be Daikin or Mitsubishi - I think I have gotten that part decided at least. I don't think they have changed much on their inside unit offerings since I was looking heavy a couple years ago.

 

[peakbagger]

One other option that is fairly new is an air to water heat pump. It looks like a minisplit but the refrigerant is all in the outdoor air unit so need to have someone charge it. (broken link removed to http://www.americansolartechnics.com/products/space-heat-pumps/)

It heats or cools water or glycol which is pumped out to the unit. There is no standard indoor head unit but it could go to a duct mounted coil or coil in an enclosure with drip pan for cooling. Ideally if the house has low temp radiators/emitters it just plumbs into the heating loop for heating.

Radiant cooling is an up and coming method of cooling, the problem is unless the controls are right on, dew point issues can be a real problem. In the damp weather conditions we have been experiencing of late I expect it would be big issue unless there is humidification done on the makeup air.

Tom In Maine on Hearth has the most experience with these as he is the one importing and selling them. John Seigenthaller had mixed comments when I took a heating course. He liked the concept but his experience with one particular brand wasn't great. Tom claims to have gone through a couple of suppliers until he got a reliable brand and I am not sure if the one John had experience with is that same as that Tom is selling.

If I was starting from scratch and didn't own a regular minisplit and had low temp radiators/emiitters or radiant tubing it might be nice option to consider but would require a lot more design on my part to get the cooling side right.