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Home Office Projects Series: Air conditioner setup

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Re: Home Office Projects Series: Air conditioner setup

#151
post #54

Earlier quoted context omitted.

It is heat pump it can cool/heat just in Japan they don't call them heat pump. Plus it is inverter based so super efficient.

Interesting. Odd, but interesting. Thanks!

Lower adoption rate of inverter air conditioner on other countries is odd for me. The only non-inverter mini split air conditioner in Japan is lowerst grade cooling-only model (and not so much cheap).

Re: Home Office Projects Series: Air conditioner setup

#152
post #87

Earlier quoted context omitted.

Heating the air drys it out... The article is about Japan. I would expect Korea has a different climate which means different considerations. (but I'm not an expert in climate)

> Heating the air drys it out... I'm not sure that's true. Hot air can hold a lot of moisture, the extreme example being steam.

What we concern is relative humidity so heating air drys.

Re: Home Office Projects Series: Air conditioner setup

#153
post #3

Is this really specific to Japanese air conditioners? Or is this really about mini-split ac that are manufactured around the world under many companies. I don't see whats specifically Japanese outside of the person using Panasonic and is in Japan. The person could be in the USA with Mrcool mini split, it would be a similar article. Edit: title has been changed to remove mention of Japan, so my nitpick may no longer v…

It's not uncommon for renters in Japan to provide the AC unit, the washing machine, and other appliances. The plumbing is already there for a split AC unit, but the appliance is not.

Air conditioner is now almost mandatory equipment for condominium meanwhile washing machine and refrigerator is an offer from some condominiums.

Re: Home Office Projects Series: Air conditioner setup

#154

Earlier quoted context omitted.

> Impossible to live without AC in Japan Come on. People lived there for thousands of years before AC.

Not in highrises. Not in megacities.

Even in rural area, temperatures in this August is sometime 36-40C (or even high) so cooler is mandatory.

Re: Home Office Projects Series: Air conditioner setup

#155
post #24

Having individual heating and cooling units ( per unit gas heaters! ) is stupendously inefficient. I travel in Asia fairly regularly so this isn't new to me, but even after all of these years I can't believe I continue to see shiny, brand new "high end" condo buildings in Hong Kong, Shanghai, Tokyo, Seoul, etc., with individual AC units hanging out the window. Contrast this with a condo in Minneapolis that I own wher…

I used to live in a building that had an electric furnace in each unit. The air conditioning coils were connected to a condenser shared with the building; the size of the piping led me to believe it might be pushing chilled water (vs. refrigerant) to each unit. No crappy boxes hanging outside, individual per-unit control inside.

Re: Home Office Projects Series: Air conditioner setup

#156

Earlier quoted context omitted.

Toronto's deep water cooling system is the largest in the world, and air conditions a good chunk of the downtown core. http://buildipedia.com/aec-pros/engineering-news/torontos-de...

Fascinating. I never knew that this existed. It's also interesting that it's also part of the city's drinking water supply: > The Energy Transfer Station includes large arrays of heat exchangers that allow the heat from the downtown chilled water loop to be rejected into the city’s drinking water supply before distribution to the public. The heat removed from the downtown chilled water loop is therefore never transfe…

It's a fantastic use of a great resource. It works because Lake Ontario gets pretty deep pretty quickly near Toronto [1]. The drinking water they bring in is extremely cold year-round:

> Three intake pipes run up to 83 m (272') deep and out to 5 km (3 miles) from the shore. The physics of cold water are factored into the design. Water is most dense at 4 degrees Celsius (39.2 degrees Fahrenheit), ensuring that the cooling water removed from the lake bottom will have a consistent year-round temperature at the system’s intake points. The cooling water to be used by the Deep Lake Water Cooling system first goes through Toronto’s standard water treatment process to become regular drinking water.

I'm not sure that there is any other large city in the world that has deep enough fresh water so close that this would work. Such a system would be welcome here in Chicago, but it isn't feasible. You'd need to go 30-40 km into the lake before it got deep enough [2].

[1] https://www.ngdc.noaa.gov/mgg/greatlakes/lakeontario_cdrom/i...

[2] https://www.ngdc.noaa.gov/mgg/greatlakes/lakemich_cdrom/imag...

Re: Home Office Projects Series: Air conditioner setup

#157
post #28

Earlier quoted context omitted.

You can't query those for the current room temp, current settings etc. So then if you mix the OEM app & your home automation app, things get messed up. IR bridges are a hack in home automation, when buying new stuff avoid them.

Just my personal opinion, but the thermometer on an A/C unit is kind of worthless unless you sit within a foot of the unit. I prefer being able to read a sensor on the opposite side of the room, or even several sensors throughout the house, rather than one on the A/C unit. I don't use any OEM app at all, just my own. The OEM ones never do exactly what I want, so I have to hack something additional onto their features…

Now premium A/C unit in Japan like from Mitsubishi Electric features high precision temp sensor to detect room temperature. Even middle model has good sensor rather than simple temp sensor.

https://www.mitsubishielectric.co.jp/home/kirigamine/product... https://www.mitsubishielectric.co.jp/home/kirigamine/product...

Re: Home Office Projects Series: Air conditioner setup

#158

Someone said Japan used to be in the title - and now that it isn't - I think it should go back. HN is mostly a US based website (with an emphasis on Silicon Valley). This methodology is wildly uncommon in the US. There's very little likelihood this kind of thing would happen in well over 90%+ of the USA. First off - if you're renting - you're not putting holes in the walls that go to the exterior and there certainly…

> Most of these units are 220V and usually there is only one or two 220V power outlets in American homes these days and they're always dedicated to the washer+dryer. Meh. Only relevant if you need to pull more than 15A or so. There are plenty of portable air conditioners for sale in the US and most are happy with 110V and less than 15A. > HN is mostly a US based website This sounds like gatekeeping. There are lots of…

Also, I believe it is illegal to install a mini split yourself in the U.S. unless you are licensed to work with freon.

Re: Home Office Projects Series: Air conditioner setup

#159

Someone said Japan used to be in the title - and now that it isn't - I think it should go back. HN is mostly a US based website (with an emphasis on Silicon Valley). This methodology is wildly uncommon in the US. There's very little likelihood this kind of thing would happen in well over 90%+ of the USA. First off - if you're renting - you're not putting holes in the walls that go to the exterior and there certainly…

> First off - if you're renting - you're not putting holes in the walls that go to the exterior and there certainly aren't any already existing. I've never seen or heard of that in the USA - particularly for apartments. This is allowed in my apartment. My closest neighbor cut a hole in the door leading outside and affixed an air conditioner to it, then made a setup of plastic bagging to make it lead all the way to th…

Portable air conditioners with a hot air vent to the outside are common, but a mini-split like in the post needs a licensed installer or you can face EPA fines.

Re: Home Office Projects Series: Air conditioner setup

#160
post #43
post #24

Having individual heating and cooling units ( per unit gas heaters! ) is stupendously inefficient. I travel in Asia fairly regularly so this isn't new to me, but even after all of these years I can't believe I continue to see shiny, brand new "high end" condo buildings in Hong Kong, Shanghai, Tokyo, Seoul, etc., with individual AC units hanging out the window. Contrast this with a condo in Minneapolis that I own wher…

> Having individual heating and cooling units (per unit gas heaters!) is stupendously inefficient. > Contrast this with a condo in Minneapolis that I own wherein heat and AC are central in the building and individual units can set their temperature to whatever they like - all run with tremendously higher efficiency. This needs some real data. There are a few central technologies that might be used. A condensing gas-f…

Those SEER 29 units are available but in my short time once selling AC units, most went for the lowest cost unit available. Those cheaper units are not as efficient.

With split units the maximum efficiency attained is in the hands of the customer. Great for customer freedom, but not so great for the environment if the lowest of the low in AC units are available.

Semi-related question: How is fresh air turnover handled in apartments with split AC units?

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