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Ductless Mini-split air conditioning

Posted by tdfromny (My Page) on
Wed, Jun 7, 06 at 9:31

I am looking to purchase a central air condition system for my house. In my research, I came across an interesting system called City Multi by Mitsubishi. Does anyone out there know anything about this system?
From what I've learned about this system is that it is a ductless system that can handle up to 16 evaporators and could put out 72000 to 100000 btus, depending on the model series. It also has many beneficial features over the (whole house) split systems.
I contacted several Mitsubishi contractors but they couldn't give me anymore information about these systems, other than what I already knew. They couldn't even give me any ball-park pricing. I then called Mitsubishi corporate HQs and talked to their technical staff. They told me that this system is normally used for commercial applications but could also be used for residential as well. It is expensive. So before I spend the money, I would like to know if anyone out there has any experience with the City Multi system, especially the S-series. I am interested to know the cost, how well it works and if there are any problems that it may have.

Thank for your help.


Follow-Up Postings:

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RE: Ductless Mini-split air conditioning

The advantages of a ductless system is that they work well in retrofit applications where traditional ducts aren't available. Or where additional cooling is desired. They have some drawbacks. You need access to be able to run the refrigeration lines. Obviously the space required is considerably less than what a duct would require but they can't be just run willy nilly. There's also a limit to how long the refrigeration lines can be (I want to say 35 ft.). You also need to hang a fairly large box (~1' x 3') on the wall or ceiling that's more obtrustive than a traditional vent. Some people just don't like that look.

I don't know enough about them to make a brand recommendation. The systems are far more popular in other parts of the world, which is why Japanese companies make a lot of them. Lately the domestic manufacturers have gotten into the game as well.

I'd think I'd try to find a installer that sells a lot of them, even if it costs a bit more. They'll have the experience to troubleshoot problems and will be more likely to have parts on hand if a repair is necessary.

Mike


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RE: Ductless Mini-split air conditioning

Mike,
Thanks for your input. I did get in touch with several local companies that vend Mitsubitshi AC systems. They didn't know any more than I did and I know nothing!

I'm interested in this system because it has many advantages over the split system ACs. You can do zone cooling (or heating). It provides comparable Btu's as split systems, its quieter and it's more efficient. However, this is all on paper for me right now and I would like to get better feel for it before spending big $$$s. I had an estimate done for a Carrier 13SEER split-system. It is very expensive - $11K. I may have to go this way but I think its crazy to AC the whole house when you not using haft of it at times.

Perhaps it would be better to post this message on a UK forum because these systems are popular there.
Anyway thanks again.
TDfromNY


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RE: Ductless Mini-split air conditioning

I would research sanyo and fujitsu


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RE: Ductless Mini-split air conditioning

The only situation I think a city multi would work in a home is if you have very large rooms or you don't want to air condition the whole house. How many indoor evaps were you thinking of having?


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RE: Ductless Mini-split air conditioning

TDfromNY

We have been quoting and installing multi-splits for some time now. We install as retrofits in home renovations and new home installs in Halifax. Before you rush out to buy a unit, research some of the new units that are coming on the market with 'inverter' technology. They are much more efficient than the 10 and 13 SEER units commonly found today. With a normal unit the compressor runs at capacity all the time whether the temperature is very hot or just moderate. With the inverter units the compressor varies it's speed to coincide with the cooling or heating load and thus consumes only the power necessary to match the exact requirement of your room. When these units operate at partial load, the energy efficiency of the system is considerably higher than at full load - and in most applications partial load conditions are present for more than 90% of the operating time. The inverter units detect changes in room temperature and adjust the compressor speed automatically giving you less temperature fluctuation and more comfort.
You only need to install units in the rooms where you spend most of your time. Typically in our climate that means the master bedroom, kitchen/family room and possibly one or two other bedrooms. We are having great success with them - quiet, quick to cool and economical operation.
I hope this helps. If you have any other questions let me know.
Oilman1


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RE: Ductless Mini-split air conditioning

I live where most people have ductless mini-splits. My current apartment has them and I am very happy with them. They are so much quieter and work so much better than any through the wall or window thing I've seen in the USA. You can also buy Multi-mini splits which actually have units which can be recessed into your ceiling and act like a mini-split but look like traditional central air. You only need a 25cm/9.84" drop to accomodate it. The hoses can be put into the walls or the ceilings. The top of the line systems here are made by Daikin http://global.daikin.com/global/our_product/ (Japanese and available in the USA). The other popular international brands I've seen around here are Panasonic, Trane, Haier, Sanyo, Siemens, Hitachi and Mitsubishi.

Here is a link that might be useful: Daikin multi mini splits


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RE: Ductless Mini-split air conditioning

Listen to a mini-split before buying.


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RE: Ductless Mini-split air conditioning

I'm am with Daikin AC a world leading manufacture of VRV (variable refriferant volume) systems. Please reveiw our web site and don't hesitate to contact me.

Here is a link that might be useful: Daikin AC


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RE: Ductless Mini-split air conditioning

While the City Multi is a very nice system, I wouldn't recommend it for a residential setting.
What you should be looking at is the Mr. Slim M-Series. They have the same type of interior units, but they are paired up to their own small outside units. (There are are also multi units which have 1 outside unit with 2 or 3 interior units.)

I would make sure to get ones that have Inverter compressors. They have the ability to modulate their capacity so you get oustanding humidity control and higher efficiencies.

My top three pics would be Fujitsu, Daikin, and Mitsubishi. In my area Mitsubishi is the cheapest, then Daikin and Fujitsu somewhat higher.

You won't need to put a unit in every single room. Each bedroom should have its own unit, and other rooms will depend on your floorplan. If it is rather open, a single larger system will take care of that pretty well. In my house I have one in each of 3 bedrooms upstairs, and one in the living room which spills over into the dining room/kitchen/hallway. These 4 systems cool the whole house very effectively.
My favorite thing is the energy savings of just cooling the bedroom at night instead of the the entire house as well as during the day just cooling the downstairs instead of the upstairs bedrooms.

Michael


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RE: Ductless Mini-split air conditioning

Ditto on the inverter technology.


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RE: Ductless Mini-split air conditioning

One thing with all of the Japanese and many of the American brands of this type of system. They're a nice system when the work but when there's a problem its usually a $@%# nightmare! They're all electronic, could be tough to troubleshoot and the circuit boards are very expensive. Alot of the parts can not be gotten off the shelf and that ups the price of service and repair considerably. The fact that even the companies that install them can't supply much info should tell you something. Sure they'll install the thing but if it doesn't work right from the git go or there's a problem down the road,, you're probably up the creek. I've been installing those things mostly in small commercial applications since the mid eighties and I could honestly say if somebody gave me one for free I still would put it in my house.


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RE: Ductless Mini-split air conditioning

I've had a Sanyo 9k BTU heat pump unit in my west facing home office thats gets hotter than the rest of the house in the summer because of it's exposure to the sun (So Calif.) I probably use it 250 days a year over the last 10 years. I have had zero problems with it other than clean the filters and change the batteries in the remote. The thing is like a Toyota and refuses to break.


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RE: Ductless Mini-split air conditioning

We've had our Soleus for about a year now. We installed it with the help of my father. The A/C company came out to charge it and pressurize the lines.
DH loves it. It's in his office on the 3rd floor, and the cooling does help to cool my office directly below on the 2nd floor.
So much quieter than a window unit.
Jennifer


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RE: Ductless Mini-split air conditioning

Been considering these split systems for some time. I am very interested in the inverter technology.

I'm in NY also.


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RE: Ductless Mini-split air conditioning

Gotta another question dealing with the same. I have a Mr. Slim M series for home office and want to connect the inside (evaporator) unit to a standard outside unit that requires a 24v connect. Is there anyway that I can 24v to this outside unit or am I required to purchase the Mr. Slim outside unit as well?


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RE: Ductless Mini-split air conditioning

johnny boi03, among other things the metering device for these systems is in the outdoor section which is kind of unconventional so the only way to make this thing work is with a matched indoor and outdoor section.


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RE: Ductless Mini-split air conditioning

I just had 2 Mitsubishi Mr. Slim units installed in my 1970's split-level house with hot water heat. They've been in a week and I love them. They are very quiet (just a bit of fan noise from the inside units) and do a great job. Our installer (a family member) tells me he's been installing them for years and they are very reliable. The refrigerant lines are covered by a plastic channel about the size of a small rain gutter, and once painted have blended in with our siding quite nicely. We have one unit in our bedroom, which keeps the upstairs comfortable, and one unit in the family room, which keeps the adjacent kitchen comfortable as well. They aren't cheap, but the quality of the units is amazing. I reccomend them highly!


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RE: Ductless Mini-split air conditioning

What's "not cheap", if you don't mind saying? I need one of these for my garage. They seem to be $700 on ebay.


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RE: Ductless Mini-split air conditioning

We must be talking about different units. The units we had installed are 15,000 btu's each. Two units installed was $5,800, plus another $1,000 for permits and electrical work.


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RE: Ductless Mini-split air conditioning

Something like this - there's a bunch of them listed. I haven't selected one yet, need to look at performance and reliability, to the extent that I can. I don't know how much of this type of information is out there. I like that they are heat pumps, so it's useful in the winter too.

I should say that I don't know the ebay lister or anything about this unit, it's just a price example.

Here is a link that might be useful: Example ebay listing


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RE: Ductless Mini-split air conditioning-HELP

hey guys and gals,
this info is great. i wish there was more of it and/or that i had found it sooner. my a/c guy comes tomorrow morning with the idea of installing an mitsubishi ms-12 split (12k btu) and wants to charge $3,000 for machine and installation.
i'm trying to find out it this is a good price.
i think i'l stall him for a day or two in case anyone here can help with info.
thanks


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RE: Ductless Mini-split air conditioning

Does the Mr Slim brand inccorporate "inverter" technology - I dont believe it does or they would mention it in the adverts. Maybe thats why its cheaper than the rest?
I want to run the line through crawl space on the second floor - but the conteactor wants to put the line on the outside of the house (easire for him!) where it would run across the South-facing entire length of the rear wing (about thirty feet + say ten feet of rise = 40 feet altogether). Surely the energy saving will be a whole lot better inside the crawl space than exposed to the sun all summer long (even if insulated).


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RE: Ductless Mini-split air conditioning

I was just looking at the Mitsubishi site. They do mention inverters. I think they said about 90% of their units have inverters (not sure on that percentage). I found that info in the FAQs. It isn't immediately obvious.


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RE: Ductless Mini-split air conditioning

When you look at a list of different Mr. Slim products, such as from a search result, you can see the word "inverter" near the beginning of some of their text descriptions.

I've noticed that Heil also makes this kind of gizmo. How many others are there that make them and who are they?

I understand why they're called "ductless", but what does "mini-split" mean?

And is this cheaper or more expensive to install than central? It seems like it would be cheaper, both due to the lack of ducts, and because the most comparable thing to it that's easy to find prices on would seem to be window AC units, which you could buy a bunch of for the prices I've seen people give for central AC installation (a few hundred apiece versus 8-12 or more thousand!). But then, if it's cheaper, central systems would have no real advantages at all for houses and these would dominate the market instead, which they don't... so what's the deal? And if they're really expensive after all, what makes them so?


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RE: Ductless Mini-split air conditioning

Here in the Middle East, mini-splits are pretty much all that's used. All the houses are concrete and have no ducts or insulation to speak of. The units are generally installed one per room, and keep up with the daily 115 - 120F temps just fine. They are somewhat louder than central AC though, and the filters are not very effective.

Here is a link that might be useful: Weather Report


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RE: Ductless Mini-split air conditioning

Two weeks ago I had a 30,000 BTU Fujitsu Halcyon "inverter" mini-split system installed in my 1000 sq ft 2 bedroom condo and I must say that this was probably the best home improvement investment I ever made. The total system cost including electrical work was about $7,800 - a bit pricey, but this included 3 evaporator units (one 12,000 BTU unit in the the living room/dining room, one 9,000 BTU in the master bedroom and one 9,000 BTU in the second bedroom). One indoor unit was mounted a good 40 feet from the outdoor unit. The condensor was installed outside on the lanai and it's much smaller than the "double-stack" units I've seen before. Inside, the units are very quiet, however there is a slight clicking sound (similar to that when you put a card on your bicycle spokes - just much quieter) on one of the units that irks me a little every now and then. I'm not sure if it's defective but I haven't asked the installer yet.

We had to run drain lines to connect to two bathroom sinks and one drain-connect needed a pump (we didn't have enough slope to make it) to handle condensate from two of the three evaporators. Here in Hawaii, it's pretty humid and the systems removed A TON of water. Before we connected to the drain lines under the bathroom sink, Two units filled up a 5 gallon bucket in about a day - amazing.

What actually amazed me (as well as the installer - this was the first "inverter" system that he installed) was how quiet the outdoor condensor unit was. We had all three zones cranking away at full blast - 30,000 BTU total - and it was quieter than a single 9,000 BTU window unit, no kidding.

In addition to the standard air filter, these units also have some kind of ionization/filtration/dust catchment system built in that needs to be cleaned at least once every 6 months - otherwise it ceases to operate.

The remotes are well designed and intuitive. The only request is to add a backlight and maybe make them RF instead of IR. It gets tiring to have to point the device at the unit everytime.

I'm waiting to see what my electric bill is as I have no idea how much power this unit is sucking. What I do understand is that they are supposed to be the MOST efficient mini-split systems on the market, and perhaps the most efficient a/c units, period. I've read that the SEER is 18, 20, etc. However the manual does not state this data. I'm hoping this system will cut my electric bill in half as I used to run 3 large window units to cool the place. The installer said the savings should be dramatic.


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RE: Ductless Mini-split air conditioning

I am also looking into installing a mini-split. I figure about 18,000Btu for the 1st floor of my house - very open floor plan. I'd like to get by with just one air handler but am wondering if I install two air handles to the same outside unit and help move the air around better? Or do I need to fork out the extra $$ for a dualzone system (even though we're talking about an area of the house that would be all the same temp. i.e. Dining room /kitchen and livingroom/study connected by a 6' wide arch.


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RE: Ductless Mini-split air conditioning

tcjohnson:
I thought that mini-splits didnt require drainage of water condensate to the interior drainage system....


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RE: Ductless Mini-split air conditioning

I have an LG 12K unit in my new house. It is used for sleeping in the master bedroom at night only. The bedroom also has ducts from the central air system, which we shut down at night.

I would say for most people it would work fine, and is pretty quiet.

But for us it has been a disappointment. Due to severe allergies we got used to running a window unit constantly in the bedroom at night (even though we had central air), reaching temps as low as 59 degrees. With a couple of quilts it was very comfortable. The new LG unit has a minimum setting of 64 and across the room it is not even that cool. we aren't getting much sleep and hate to do it, but the window unit might go in one of my high $$ Marvin windows so we can get some sleep.

I don't get much sympathy nor any ideas for outsmarting the thermostat as most people feel like setting a thermostat at 60 is somehow immoral, but if a $250 window unit will do it you would think the minisplit would.

Seems like mine was about $1000, but I don't know the breakdown of the installation charges. It was installed by the same guy that put in 2 Trane XL16i units and an ERV.


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RE: Ductless Mini-split air conditioning

I'm in Texas and have not been able to locate anyone local who carries mini-split systems (they're not common here as we mainly have central a/c). Did any of you purchase these unit direct from an AC company or off the internet? thanks


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RE: Ductless Mini-split air conditioning

Jillh:

Just a bit of warning...you can buy Mitsubushi mini-split systems on-line...but they won't honor warranty unless it is installed by I believe one of their approved contractors (or at least a certified techinician). They don't want people buying them and trying to install themselves or by someone not qualified.

I believe it is Fujitsu who won't warranty any of their products sold over the internet...

So do try to find installer from the maker you go with. I have a new Mitsubishi mini-split heat pump system and really like it. Check their website

Here is a link that might be useful: Mitusbishi mini split


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RE: Ductless Mini-split air conditioning

Adenn1 - you are the answer to my prayers!!! I had looked at the Mitsubishi website but could not locate anything, but you provided the link to Mitsubishi ELECTRIC and that solved everything! I have also forward that link to my BIL who has the same type of problem in Virginia. Thanks!


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RE: Ductless Mini-split air conditioning

I have an inexpensive 24K btu Soleus unit for my west facing garage. Even in the dead of summer here in Phoenix, it makes the garage liveable to work in. The one and only time I used it as a heat source in the winter, it split the coil. They replaced it, but I won't use the heat again. Not much need for that here anyway. I realize this is a cheap unit, but I only use it a few times a year, so I'm hoping it will give me a few years service. But as to performance, it works very well.


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RE: Ductless Mini-split air conditioning

When you are all talking about air conditioning, I assume you mean heat too? I have a large room with vaulted ceiling above a garage which we are converting into a small guest room/bath, with the balance of the space being left open for an art studio. We are in Pennsylvania so need heat and a/c. What would any of you recommend in this scenario?


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RE: Ductless Mini-split air conditioning

Closing in on an HVAC solution for my SoCal home which has no ducting or attic space, it appears a mini-split heat pump system is what I need, most likely one dual-zone + one tri-zone for a 2000sf house. I am trying to choose between Fujitsu and LG. There appear to be few/no reports of problems or breakdowns with any of the minisplit brands mentioned above - wow! - are all of these systems really that good & reliable?? We are looking hard at LG's "Art Cool" units, which are very appealing visually, but I am concerned about whether they are as reliable as Fujitsu, as the LG's don't seem to be talked about much. Anyone heard good or bad reports about LG's minisplits (especially their Art Cool line)? Also wondering if minisplit heat pump systems in general will be energy efficient below freezing temps in the 20-32F range?


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RE: Ductless Mini-split air conditioning

herbl -

I would go with the Fujitsu units. They are based around an inverter compressor which means it is variable speed. The capacity will ramp up and down to match whatever the current conditions need. This also means that they heat very well at colder outside temperatures. (You may still need some kind of supplemental heat though). They are very energy efficient with SEERs of 17-21

Other companies also make inverter based units. Mitsubishi, Daikin, Sanyo, Samsung as well as a couple others. Their systems are comparable to Fujitsu.

Michael


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RE: Ductless Mini-split air conditioning

I have a 375 SQ Ft area that is both the living room and dining room kitchen, it has about a 13 foot ceiling, i'm wondering if I should go with the 16,200 BTU Mitsubishi unit or the 22,000 BTU unit..........I assumed with a room that size 16,200 would be the size to go with, the estimate I got from a contractor said I was inbetween but should go with the 22,000 BTU unit.

My question is, i have heard that ductless units are more efficient than Central air due to no duct loss and models with inverters are also more efficient and they also say going to big is not good as well.........could the contracter be basing his recommendation on his experience with central air models that dont have inverters.

Now I dont want to buy a unit that is TOO small, but i dont want one that is too big either and from the recommendations i have seen, 16,200 BTU's seems like plenty for 375 sq feet............does the high ceiling make THAT much difference, i assumed that cool air falls so the 13 foot ceiling wouldnt be that much of a factor?

Thanks
Mike


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RE: Ductless Mini-split air conditioning

JillH: Glad I could help...good luck to you.

Peyton: I am assuming this is a room over a detached garage..or at least a room with no ducting present? If this is the case, then I think looking into a mini-split heat pump system would be a good idea. I too live in PA and my system will provide cooling and heat to my new room. The issue for you is the room adequately insulated? I would also suggest to you to have a professional complete a heating/cooling load for the room (Manual J). This way you know exactly what size unit you need.

The heating issue with heat pump mini-split systems was one that I found to have two camps...I found some HVAC guys who said I would need additional heat for the room to help supplement the heat pump...some wanted to put in electric baseboard and others wanted to install units with electric strip heaters in the heat pump unit.

The other side said the new heat pump systems with the inverter compressor would do a find job of taking care of my heating needs. I went with this side...and will find out how things work out this winter. I trust the opinion of the installer I went with...so I have no concerns.

Mike:
Is the quote you got based on a heating and load calculation? Sounds like you might be wise to find someone to come out and run one for you and see what they recommend. Sounds like a bit of over-kill for the 22 system...and no you do not want an over-sized system. Jumping up to the 22 has also got to me more $$...so you have to consider that.


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Sanyo multi split heat pumps

Has anyone heard of problems or issues with Sanyo's multisplits? Are they as reliable as the Fujitsu?

Sanyo's multi seems to have all the features I want + the wall units are a bit slimmer than Fujitsu which is nice.

The only downside I can see is the Sanyo multi's are only 13/7.7 SEER/HSPF compared to Fujitsu's 15/9; I wonder how big a difference would this make on my electric bills? (located in S. California)?


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RE: Ductless Mini-split air conditioning

I have misplaced my user manual for our soleus mini split system and I am having a terrible time trying to figure out the remote control. If anyone has one, would you kindly send me the instructions on how to use the remove. Outside - FAN ON/Off Temp. Inside Sleep swing mode can set timer hi power. Thanks in advance


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RE: Ductless Mini-split air conditioning

Link below...

HTH
Chris

Here is a link that might be useful: Manual


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RE: Ductless Mini-split air conditioning

Great info here. We have 1922 cottage..no ducts to 2nd floor. Two of the 4 tiny bedrooms are uncooled, except for whatever drifts up the stairs. No chases either to these 2 bdrooms. Knob and tube wiring on the second floor. Little insulation. House is used for summer beach house primarily.
Is there a distributor/installer of any of these systems in the NW Indiana/ Chicago area. Thanks. Bev


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RE: Ductless Mini-split air conditioning,

bump


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RE: Ductless Mini-split air conditioning

Bev:

Scroll up through a few posts and you will see where I put a link to the Mitsubishi website. You can put in your zip code and find a contractor in your area. You can do the same for Fujitsu.


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RE: Ductless Mini-split air conditioning

Thanks adenn, Bev I appreciate


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RE: Ductless Mini-split air conditioning

Hello,

Would like to know how many BTUs (for 1 wallmount system)would I need for two floors of 690 sqfeet (each floor).

The Unit will be on the 2nd floor in the middle between 2 bedrooms and a washroom (over washroom door facing master bedroom).

It will be a dual split system.
-------------------------------------
Also would like to know which is a safe reliable cost efficient brand,

example of wall mounted (split systems) air conditions I've heard of:

Fujitsu (they give 10 years warranty parts and labour)
Mitsubishi (6 yrs parts and labour however been making them longer)
Daikin (6 yrs parts and labour)
Igloo
York
Carrier
Grey

All about the same price...

-----------------------------------
Finally, is it better to get a dual system (with heat pump), from my understanding they are almost the same price
and the advantage is that it has a variable BTU which may save some $$. Since the heat pump will be at the higher level then it wont heat as much however it is coming at about the same price. Then again more electronics in a system more chances of malfunctioning sooner?

Thank you,
Stelios


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RE: Ductless Mini-split air conditioning

Considering the Fujitsu Halcyon "inverter" mini-split system . It's clearly been around for years. Do those of you that have THIS UNIT recommend it ? I'd like feedback on it either way before I purchase it.

Thanks !!


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RE: Ductless Mini-split air conditioning

VRF Systems work very, very well...use them extensively. Line runs not limited to 35ft...more like 10 times that. 16 zones on one condenser...not unless its a 3-phase CityMulti. The smaller 3 and 4 ton systems can only support 7-9 air handlers in the smallest BTU range.

need more... info@airstarsolutions.com


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RE: Ductless Mini-split air conditioning

good luck with the fujitsu halcyon inverter system. here in pa. when the temps dropped this winter to under 10degrees no heat. 2 days before the temps went up past 20. they went out again yesterday and it was only 32.


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