Mitsubishi wall air conditioner

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Determined
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Mitsubishi wall air conditioner

Post by Determined » Fri May 18, 2018 6:14 am

Who has experience with these? We are looking at a brick Victorian home without central air. It would be for the upstairs which has three bedrooms and a full bath. It's approximately 800 square feet total with 14 ft ceilings and two open stairwells. One is the main hall starwell, the other goes out of a bedroom. The door is at the bottom.
Last edited by Determined on Fri May 18, 2018 7:29 am, edited 1 time in total.

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fizxman
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Re: Mitsubishi wall air conditioner

Post by fizxman » Fri May 18, 2018 6:53 am

I have two experiences living with the Mitsubishi Mr. Slim, one direct and one less direct. I can't really comment on cost or installation though.

About 12 years ago or so, I moved into a friends house and lived in the renovated attic on the third floor. The first summer I had one of those free-standing air conditioners that had hoses running to the one window. That thing could not keep the attic cool. So my friend, being the nice guy he is, had a Mitsubishi Mr. Slim installed. That thing was great. It was able to keep the 600-800 sq ft attic cool enough to where I was very comfortable.

My parent's house doesn't have central air conditioning so my dad would put in /take out 4-5 window units every year. He didn't like doing this every year so they looked into the Mr. Slims. My parents ended up getting four for their house. One unit for the entire upstairs, which consists of the master bedroom and bathroom as well as an office. Then there's one unit for each of the two downstairs bedrooms and one unit for the living room, dining room, and kitchen. The two units for the downstairs bedrooms are smaller than the other two, by how much, I don't know. Regardless, my parents love them. The Mr. Slims keep their house nice and cool in the summer and they also use them for heating in the winter as well. They don't heat the house solely with the Mr. Slims, they have oil heat so they set the thermostat to the low to mid-60s and use the Mr. Slim in the living room to keep the downstairs a little warmer.

So in my two experiences with them, I thought they worked great.

bob60014
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Re: Mitsubishi wall air conditioner

Post by bob60014 » Fri May 18, 2018 7:18 am

No experience with a install or long term reliablity, but we spent a month in Australia recently and these units are everywhere. We stayed at relatives homes and found the units to work quite well in the summer heat. It took me awhile to get used to its operation but once I did I found it to work ok. You may find some corners that may not cool down enough and may need a small fan to circulate the air.

jebmke
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Re: Mitsubishi wall air conditioner

Post by jebmke » Fri May 18, 2018 7:22 am

bob60014 wrote:
Fri May 18, 2018 7:18 am
No experience with a install or long term reliablity, but we spent a month in Australia recently and these units are everywhere. We stayed at relatives homes and found the units to work quite well in the summer heat. It took me awhile to get used to its operation but once I did I found it to work ok. You may find some corners that may not cool down enough and may need a small fan to circulate the air.
I have a Mistubishi Mr. Slim for a space that is not covered by our central system. I run a ceiling fan on low all the time to keep the air mixing. I reverse it in the winter.

This system is very efficient. Without any electric resistance backup I can get heat out of it with the outside temp as low as 10-degrees.
When you discover that you are riding a dead horse, the best strategy is to dismount.

Spirit Rider
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Re: Mitsubishi wall air conditioner

Post by Spirit Rider » Fri May 18, 2018 7:27 am

Mitsubishi is but a brand. These are called ductless and/or mini splits ACs. The are very common in Asia and parts of Europe. I have had a private labeled Daikin mini split for more than twenty (20) years. Daikin is the largest AC manufacturer in the world. Most mini splits from well known American brands are in fact private labeled Asian products. Notable other name brands are Fujitsu and LG. There are also several lesser know brands.

msk
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Re: Mitsubishi wall air conditioner

Post by msk » Fri May 18, 2018 7:30 am

How much cooling you experience depends solely on the cooling capacity installed. Your local climate makes a HUGE difference. I live in a very hot climate and we need around 12,000 BTU (one ton) per 120 sq ft of typical floor space. Most climates will require much less cooling. Three bedrooms to be cooled by one unit? Sounds like a very temperate climate... You need to talk to a knowledgeable salesman who is in your climatic area and explain whether you will leave all doors open or shut. Obviously if all doors are shut at night then each room will require its own unit. He can quickly tell you what cooling capacity you need, either for each room or for the whole floor or even house. An over-sized air conditioner on an upper floor can easily cool an entire house in a temperate climate. The brand does not matter much, except if you go for the super cheap mysterious Chinese non-brands. Just pay attention to the warranty offered.

jchris
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Re: Mitsubishi wall air conditioner

Post by jchris » Fri May 18, 2018 7:33 am

I have two of them in my house - they work great. We've had them for about 10 years now - had them installed when we renovated our main floor. When we opened up the space, we removed two walls, one of which contained the air supply ducts for two upstairs bedrooms. So the mini-split A/C units were the only feasible solution to cooling those rooms.

e5116
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Re: Mitsubishi wall air conditioner

Post by e5116 » Fri May 18, 2018 8:13 am

In my experience, they work well but are not any cheaper to install than a traditional central air system when doing it for the entire house, so you should like something about them over central a/c if choosing them (although you indicated it's just for upstairs, so maybe that changes the cost calculus). They're often more energy efficient largely because you choose which exact room/unit to turn on so you're not cooling rooms you're not in (some might argue this is less "convenient" -- I understand you can have zones with central a/c but in practice you're not going to have a zone for each room).

Some people don't like the look of ductless/mini-split units on the walls and also for re-sale, ductless units are technically NOT Central a/c so it still will say wall/window units on the listing.

Space pac is another option if you want to avoid opening up too many walls, but the installation cost of space pac is even higher (but you don't have to pay for fixing up walls as much!).

Spirit Rider
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Re: Mitsubishi wall air conditioner

Post by Spirit Rider » Fri May 18, 2018 8:27 am

msk wrote:
Fri May 18, 2018 7:30 am
How much cooling you experience depends solely on the cooling capacity installed. Your local climate makes a HUGE difference. I live in a very hot climate and we need around 12,000 BTU (one ton) per 120 sq ft of typical floor space.
Either that is a typo or you live on Mercury. Even in US Zone 5, 25 - 30 btu per sq ft is more than adequate. 100 BTU per sq ft, not a chance.

So you are going to tell me that a 2000 sq ft house needs 20K BTU or 10 tons, I think not.

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Smorgasbord
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Re: Mitsubishi wall air conditioner

Post by Smorgasbord » Fri May 18, 2018 9:33 am

Spirit Rider wrote:
Fri May 18, 2018 8:27 am
msk wrote:
Fri May 18, 2018 7:30 am
How much cooling you experience depends solely on the cooling capacity installed. Your local climate makes a HUGE difference. I live in a very hot climate and we need around 12,000 BTU (one ton) per 120 sq ft of typical floor space.
Either that is a typo or you live on Mercury. Even in US Zone 5, 25 - 30 btu per sq ft is more than adequate. 100 BTU per sq ft, not a chance.
So you are going to tell me that a 2000 sq ft house needs 20K BTU or 10 tons, I think not.
I believe MSK lives in Oman, so while not quite Mercury, it's close. :D

maroon
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Re: Mitsubishi wall air conditioner

Post by maroon » Fri May 18, 2018 9:59 am

I own one. It's a Mitsubishi and it works well. No issues.

My first mini-split was a Daikin and I would NOT recommend you buy one. I learned Daikin does not provide direct service to consumers! I had a technical question after my mini-split was installed; my dealer referred me to Daikin and Daikin referred me back to the dealer. Neither one answered my question. Side note: the owner's manual does NOT even contain a Daikin customer service phone #! I had to Google it.

Also, my Daikin unit performed flawlessly, but seemed super LOUD. I eventually found an online review which claimed that the Daikin mini-splits work well but are louder than other brands. This matches my personal experience. I have very sensitive hearing, so eventually had the Daikin taken out and a Mitsubishi installed.

If Daikin wants to contact me and reimburse me, then I'll be happy to say nicer things, like how great the company is to buy back my unit that's currently being stored in my garage. It's too expensive for me to throw out and I'm loath to sell it on Craigslist for the pittance I'd get.

Alf 101
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Re: Mitsubishi wall air conditioner

Post by Alf 101 » Fri May 18, 2018 10:09 am

This is a well-timed thread, as this is something I've been considering. Recently we moved to a 2200 sq. ft house in USDA zone 5a/5b. The home has oil heat, no AC, and is ductless with baseboard heat. Having traveled a bit in Asia, Australia, and New Zealand, I've seen mini split AC units widely deployed, so it's an option for us.

The initial plan is to survive our first summer. So far the house seems well insulated, surrounded by woods, and has skylights and plenty of windows -- promoting air flow. We may be able to get by just adding a ceiling fan, and an occasional box of popsicles to suffer through the handful of tougher days.

If it is hot during the summer, we'll want to address it though. My wife is less keen on a window box, and has suggested a portable floor AC model. These seem to fall in the $300-600 range, but I have some doubts about their efficacy. Depending on the price of a mini split system, that could instead be the best place to start.

For specifics, I'd probably put one in the our bedroom -- maybe 400 sq. ft or so. So a few questions:

1. What kind of price range can I expect to install a single unit for an upstairs room?

2. How much more expensive is it to add units after the initial installation? Let's say we have a kid in a year, and want to add a unit in their bedroom, or in an office space downstairs. Is it easy to tie these into the compressor, or is it much more cost effective make all the installations at the start?

3. Do the mini split units always have to go on outside walls?

There is much I don't know. Thanks.

VaR
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Re: Mitsubishi wall air conditioner

Post by VaR » Fri May 18, 2018 10:38 am

Determined wrote:
Fri May 18, 2018 6:14 am
Who has experience with these? We are looking at a brick Victorian home without central air. It would be for the upstairs which has three bedrooms and a full bath. It's approximately 800 square feet total with 14 ft ceilings and two open stairwells. One is the main hall starwell, the other goes out of a bedroom. The door is at the bottom.
I have a Mitsubishi Mr. Slim 4 zone unit for my 2-bedroom condo, one in each bedroom and two in the kitchen/living/dining/great room. Open stairwell to the downstairs bedrooms.

They work great, the only hassle was the design of the system - specifically figuring out which walls they would go on that would properly circulate air in the great room but also be able to provide proper drainage for the condensate lines for the evaporator/blower in each room. Plus there was running the refrigerant lines in the ceiling and/or walls to the outside compressor. We ended up running two of the drains to a condensate pump in the basement.

The cheapest option is to have the units on the outside walls of the room and to run the condensate line out and down and to run the refrigerant lines all outside. Running them inside walls and having a condensate pump and running the pumped line out was an additional expense - lots of drilling through studs and replacing drywall and ceiling.

Note to Alf: You can find online prices for the equipment itself. Installed prices will vary a lot by location and the difficulty of your install. Also, it's always ultimately cheaper to install everything at once but you can buy a multi-zone compressor and only install one indoor unit at first. If you go this route you would buy a compressor unit that is big enough and has enough zones to cover your anticipated full installation. Alternatively, I've seen where it was actually cheaper to install multiple single-zone split systems, one for each room.
Last edited by VaR on Fri May 18, 2018 10:41 am, edited 1 time in total.

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Pajamas
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Re: Mitsubishi wall air conditioner

Post by Pajamas » Fri May 18, 2018 10:39 am

Determined wrote:
Fri May 18, 2018 6:14 am
It would be for the upstairs which has three bedrooms and a full bath. It's approximately 800 square feet total with 14 ft ceilings and two open stairwells. One is the main hall starwell, the other goes out of a bedroom. The door is at the bottom.
They work very well for single rooms and retrofit situations. The complications are that you have multiple rooms and a fairly large volume because of the ceiling height. It is also the upper floor so will get hotter than the lower floor. You might have to use more than one unit although there are "multi-zone" systems that might work.

Make sure that the HVAC company that designs and installs the system is competent and experienced with similar complex situations involving split duct systems rather than simply buying one at a building supply store and installing it or having it installed. You might even consider getting an HVAC engineer or similar to make recommendations about the system.

e5116
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Re: Mitsubishi wall air conditioner

Post by e5116 » Fri May 18, 2018 10:56 am

Alf 101 wrote:
Fri May 18, 2018 10:09 am
If it is hot during the summer, we'll want to address it though. My wife is less keen on a window box, and has suggested a portable floor AC model. These seem to fall in the $300-600 range, but I have some doubts about their efficacy. Depending on the price of a mini split system, that could instead be the best place to start
Don't have answers to the rest of your questions in the post, but you are correct that portable floor ACs are extremely inefficient compared to window units. I would not recommend them unless for some reason you have no other choice and a window unit is not an option. Yeah, window units don't look the best, but neither do those portable ones (and they take up floor space).

To quote the wirecutter: "Portable air conditioners are fine—if you have no other way to get comfortable. Compared with other types of room ACs (such as window or in-wall units), portable ACs cost more, use much more energy, and just don’t cool as effectively. In mild climates, a strong fan or evaporative cooler might do the trick for a lot less money. But even though portable air conditioners are mediocre at best, they’re better than no air conditioner at all. "

talzara
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Re: Mitsubishi wall air conditioner

Post by talzara » Fri May 18, 2018 11:43 am

Smorgasbord wrote:
Fri May 18, 2018 9:33 am
Spirit Rider wrote:
Fri May 18, 2018 8:27 am
msk wrote:
Fri May 18, 2018 7:30 am
How much cooling you experience depends solely on the cooling capacity installed. Your local climate makes a HUGE difference. I live in a very hot climate and we need around 12,000 BTU (one ton) per 120 sq ft of typical floor space.
Either that is a typo or you live on Mercury. Even in US Zone 5, 25 - 30 btu per sq ft is more than adequate. 100 BTU per sq ft, not a chance.
So you are going to tell me that a 2000 sq ft house needs 20K BTU or 10 tons, I think not.
I believe MSK lives in Oman, so while not quite Mercury, it's close. :D
Oman is hot, but not that hot. It's cooler than Arizona.

The average high temperature in the hottest month of the summer is only 105 degrees in Muscat, Oman. It's 115 degrees in Phoenix, Arizona.

The record high temperature is 121 degrees in Muscat and 122 degrees in Phoenix.

I wonder if houses are insulated in Oman. That could explain why the air conditioner has to be 4 times the size.

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Re: Mitsubishi wall air conditioner

Post by N1CKV » Fri May 18, 2018 11:53 am

I believe the system type you are referring to is a "mini-split".
There is several manufacturers of this system type. It is an excellent choice for a variety of needs. My parents have on on the "addition" on their house and it is very efficient and quiet, yet still easily keeps the area comfortable even in the summer, this is in the deep south.
I have met a lot of people that claim to love money, but they also seem to be the same people that are in the biggest hurry to get rid of it.

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Smorgasbord
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Re: Mitsubishi wall air conditioner

Post by Smorgasbord » Fri May 18, 2018 12:02 pm

talzara wrote:
Fri May 18, 2018 11:43 am
Oman is hot, but not that hot. It's cooler than Arizona.
The average high temperature in the hottest month of the summer is only 105 degrees in Muscat, Oman. It's 115 degrees in Phoenix, Arizona.
Phoenix has higher highs, but I'd still call Oman hotter. For example, this coming Sunday, Muscat will have a high of 90, low of 83, and 51% humidity. Phoenix will have a high of 97, a low of 71, and 13% humidity.
https://weather.com/weather/tenday/l/Mu ... X0003:1:MU
https://weather.com/weather/tenday/l/Ph ... Z0166:1:US

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Re: Mitsubishi wall air conditioner

Post by Ged » Fri May 18, 2018 12:03 pm

I own a Mr Slim (Mitsubishi Ductless Mini Split) which I had installed in my garage which I use as a workshop. It allows me year round comfort at a reasonable cost. Never had any trouble with it or needed any maintenance other than periodically cleaning the filter. There are several manufacturers of this type of equipment. As far as I can tell Mitsubishi is highly regarded in this field.

Having it independent of my central air/heating system gives me great flexibility plus keeps whatever I have going on in the garage from affecting the rest of the house.

For a home that does not have air ducts I would think it would be a good solution.

You want someone with experience in your type of installation and climate to select and install the equipment.

talzara
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Re: Mitsubishi wall air conditioner

Post by talzara » Fri May 18, 2018 12:05 pm

Alf 101 wrote:
Fri May 18, 2018 10:09 am
3. Do the mini split units always have to go on outside walls?
No, it's just simpler and cheaper. A ductless mini-split requires the installation of a refrigerant line, a condensate line, and an electrical cable. It's easiest to run it outside the house and then punch through the wall to the air handler.

You can run it to the interior of the house if you want, but there are limits on how long the refrigerant line can be. The condensate line drains by gravity, so it has to be pitched the whole way.

In the United States, mini-splits are very expensive to install because the demand is low. Its much cheaper in countries where mini-splits are common and central air conditioning is rare.

talzara
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Re: Mitsubishi wall air conditioner

Post by talzara » Fri May 18, 2018 12:19 pm

Smorgasbord wrote:
Fri May 18, 2018 12:02 pm
Phoenix has higher highs, but I'd still call Oman hotter. For example, this coming Sunday, Muscat will have a high of 90, low of 83, and 51% humidity. Phoenix will have a high of 97, a low of 71, and 13% humidity.
https://weather.com/weather/tenday/l/Mu ... X0003:1:MU
https://weather.com/weather/tenday/l/Ph ... Z0166:1:US
Air conditioners are sized for the 99th percentile temperature. The low temperature does not matter for sizing. It only determines how much you have to run the air conditioner at night.

Humidity matters, but it mostly migrates through air exchange. Water vapor goes through the walls slowly.

Maybe houses in Muscat are poorly-insulated and leaky.

Rwsavory
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Re: Mitsubishi wall air conditioner

Post by Rwsavory » Fri May 18, 2018 1:21 pm

A year ago we had a Mitsubishi multi-zone system installed on the first floor of our 2 story circa 1909 home. There are three indoor units and a two-fan outside compressor cooling (and occasionally heating) about 1800 square feet. We live in a very hot and humid climate. It works great and is very quiet. We have a traditional central air installation for the upstairs, and we wish we could replace it with a Mitsubishi system, but the central unit is still relatively new.

One major advantage of a ductless system such as the mini-split is that you're directly conditioning the space. When you run ducts through an attic or other unconditioned space they pick up ambient heat, reducing efficiency.

Determined
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Re: Mitsubishi wall air conditioner

Post by Determined » Fri May 18, 2018 1:34 pm

Thank you for all the great responses. The topic just came up when my fiance said his friend had installed one recently and loves it. The house has duct work and we had discussed adding a/c. When we looked at again yesterday, the lower level was only 65 degrees even though it was 80 outside. The upstairs was warmer, but not hot. We live in Ohio where summers can get hot and muggy. I imagine there would be separate units for each bedroom. Always interesting to find out what people know here.

3504PIR
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Re: Mitsubishi wall air conditioner

Post by 3504PIR » Fri May 18, 2018 3:51 pm

I would consider the effect of putting a split system on the value of the home if it has a level of character worth saving or is historical. I would much rather install a high velocity system than hang a unit up by the ceiling on a Victorian home. High velocity systems use ducts like a traditional system, but the ducts are small and easier to fit into historic homes. Ducts are usually about 2 inches in diameter and pvc much like the plumbing that is already in the house in size.

Wellfleet
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Re: Mitsubishi wall air conditioner

Post by Wellfleet » Fri May 18, 2018 4:00 pm

Fujitsu has a much nicer lineup of options including ceiling mount units that look like duct heads.

We have 2, neither are the ugly wall mount units.

VaR
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Re: Mitsubishi wall air conditioner

Post by VaR » Fri May 18, 2018 6:27 pm

Wellfleet wrote:
Fri May 18, 2018 4:00 pm
Fujitsu has a much nicer lineup of options including ceiling mount units that look like duct heads.

We have 2, neither are the ugly wall mount units.
Mitsubishi has this as well, but it's more expensive both to buy the hardware and to install it. It does have a very clean look, though.

msk
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Re: Mitsubishi wall air conditioner

Post by msk » Sat May 19, 2018 1:33 am

talzara wrote:
Fri May 18, 2018 12:19 pm
Smorgasbord wrote:
Fri May 18, 2018 12:02 pm
Phoenix has higher highs, but I'd still call Oman hotter. For example, this coming Sunday, Muscat will have a high of 90, low of 83, and 51% humidity. Phoenix will have a high of 97, a low of 71, and 13% humidity.
https://weather.com/weather/tenday/l/Mu ... X0003:1:MU
https://weather.com/weather/tenday/l/Ph ... Z0166:1:US
Air conditioners are sized for the 99th percentile temperature. The low temperature does not matter for sizing. It only determines how much you have to run the air conditioner at night.

Humidity matters, but it mostly migrates through air exchange. Water vapor goes through the walls slowly.

Maybe houses in Muscat are poorly-insulated and leaky.
Frankly, a local, knowledgeable salesman can give a rule-of-thumb suited for the local climate. I would add another suggestion for older homes that have ducted-air heating. Least hassle solution is to change over your boiler to a heat pump (+ a small oil fired booster if you are in the northern states). Did that for one home and wondered why it took me so long to make the decision. The cooling comes as a bonus, instant central air :D Heating by heat pump/exchanger is about 500 to 600% efficient. For each Watt electricity you spend, you get 5 to 6 Watts heat (sucked from the atmosphere) while burning a fossil fuel gets close to, but still less than 100% of the Watts you burn. Huge difference that shows how cheap fossil fuels used to be decades ago. OK, the heat pump technology also was not yet mature... Most of the complaints against retrofitted heat pumps (for winter heating) are because people install units that are undersized. Going up to the next capacity size does not cost as much as the aggravation of always feeling chilled mid-winter. Ditto for summer cooling. Going the next step-up in cooling capacity for a wall split unit does not cost much. What gets expensive is running costs. Set the temperature very low in the summer and you use a lot of electricity. Take delicate care of that thermostat...

jbuzolich
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Re: Mitsubishi wall air conditioner

Post by jbuzolich » Sat May 19, 2018 1:51 am

Parents have a two zone Mitsubishi mini split at their house in Oregon and love it. We put a four zone Fujitsu mini split in our cabin towards Yosemite and love it. The cabin really wouldn't be as usable as it is now for us without that heating and cooling capability.

msk
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Re: Mitsubishi wall air conditioner

Post by msk » Sat May 19, 2018 2:08 am

Spirit Rider wrote:
Fri May 18, 2018 8:27 am
msk wrote:
Fri May 18, 2018 7:30 am
How much cooling you experience depends solely on the cooling capacity installed. Your local climate makes a HUGE difference. I live in a very hot climate and we need around 12,000 BTU (one ton) per 120 sq ft of typical floor space.
Either that is a typo or you live on Mercury. Even in US Zone 5, 25 - 30 btu per sq ft is more than adequate. 100 BTU per sq ft, not a chance.

So you are going to tell me that a 2000 sq ft house needs 20K BTU or 10 tons, I think not.
The very first house I built was way back in 1974. It was 2350 sq ft and had a very carefully engineered/specced central cooling system of 2x2.5 ton units. It was still in my pauper days so every $ counted. Sufficient for normal occupancy on normal days, but inadequate if we had a party or large crowd for lunch mid-summer or on the hottest days. My current, ridiculously sized MacMansion is 14,000 sq ft and has 97.5 ton cooling installed. Coped very well for a large wedding party... Installing moderately excess cooling capacity is not expensive, but running it is. I prefer to have the capacity instantly available when needed.

I was also surprised at how little cooling capacity was installed in 2 homes I owned in Canada, around 2 tons and 2.5 tons for a 2000 sq ft home and a 3000 sq ft home, if I recall correctly, but of course those heat pumps were sized for the winters (with oil-fired boosting). Local climate matters...

mikebee
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Re: Mitsubishi wall air conditioner

Post by mikebee » Sat May 19, 2018 10:12 am

One Mr Slim in our last house.
Three Dakins in our present house.
All worked/work reliably and well but expect eye watering electricity bills.
Heat pumps much cheaper to run but do not oversize.
One ton per 650 square feet, no more as inefficient and constantly cycling on and off.

talzara
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Re: Mitsubishi wall air conditioner

Post by talzara » Sat May 19, 2018 10:28 am

msk wrote:
Sat May 19, 2018 1:33 am
Frankly, a local, knowledgeable salesman can give a rule-of-thumb suited for the local climate.
That would explain why your air conditioner is so large. The salesman makes more money by selling you a larger unit.

Larger air conditioners extract less humidity because they shut off before the coil gets really cold. It's better to buy the smallest air conditioner that will satisfy your needs.

BrooklynInvest
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Re: Mitsubishi wall air conditioner

Post by BrooklynInvest » Sat May 19, 2018 12:16 pm

Installed several in my late 1800s brownstone. Love 'em. One caveat. Make sure your installer is listed on Mitsubishi's site. My first install resulted in a law suit. Also I believe the warrantee may be longer. My ignorance.

That aside my place might be similar to your's - three floor brownstone. I have tenants on the first floor -

They have two units and rarely need 'em 'cause it's cool there even in summer.

My open plan parlor floor has one larger wall unit and that more than suffices

Upstairs I have two industrial units "hidden" in the top of closets and one wall unit in a bedroom. Three units overkill in a way but it's easier to have one unit per bedroom.

Cruise
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Re: Mitsubishi wall air conditioner

Post by Cruise » Sat May 19, 2018 12:43 pm

We have had two Mitsubishi split air systems for many years. One smaller unit is in our bed room, and is sufficient to cool that very nicely. If we open up our bedroom door and blast the fan, this unit is sufficient to cool the rest of our rooms on that floor (which is relatively small).

A larger unit is in our living room, and blows enough cool air to cool our living room, dining room and kitchen.

SittingOnTheFence
Posts: 295
Joined: Sun Sep 27, 2015 5:30 pm

Re: Mitsubishi wall air conditioner

Post by SittingOnTheFence » Sat May 19, 2018 11:22 pm

Regarding cost, last month I received a quote for a Mitsubishi Ductless heat & cooling heat pump plus 3 ductless heads. It was ~$13k. I figured I would need 2 heat pumps and 7 or 8 heads for my rambling ranch style home. I didn't accept the bid.

bigcmagor
Posts: 53
Joined: Tue Aug 14, 2012 4:06 pm

Re: Mitsubishi wall air conditioner

Post by bigcmagor » Sun May 20, 2018 7:40 am

We installed a Fujitsu unit in our second floor, cathedral ceiling bedroom last year. We would have to run the central A/C unit all day to push enough cold air to the bedroom to accommodate sleeping during the summer months. Our energy use put us on the utility dunce list for consumption for comparable sized homes.

Now we are consuming about half the electricity of comparable homes and we keep the bedroom at a chilly 69 degrees all summer long and rarely run the central A/C unit. Our system runs on a 15 amp circuit and set us back $5,000 installed. Best $ I may have ever spent.

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