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Home Office Projects Series: Air conditioner setup

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Re: Home Office Projects Series: Air conditioner setup

#51

Post by smileysteve »

rsync wrote: 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…

This is not limited to Asian, single units are also common in European, and Central American cities; (likely buildings that existed prior to air conditioning ubiquity -- which also related to sealing of the home);

Much of this is related to air conditioning attitudes as well; Do you need to have comfortable temperatures in the entire house or just a living room with comfort when working, watching tv, eating dinner.

tldr; air conditiong views vary from necessary to an accessory; where they're an accessory, one of units are most common

Re: Home Office Projects Series: Air conditioner setup

#52

Post by boxed »

Just by luck before the pandemic hit I installed ground heat exchange with cooling for my house. This is so efficient the cooling is free. How do you ask is that even thermodynamically possible? Well all the heat from the cooling is used to heat the hole, which you get back in cheaper heating of the house from the same hole in winter. It's amazing!

Re: Home Office Projects Series: Air conditioner setup

#53

Post by johnbrodie »

djanogo wrote: post #4

Where are the refrigerant lines, how did they run them from compressor to evaporator?, I thought the biggest issue with AC self install is filling the refrigerant and sealing those lines.

I recently installed a mini-split in my garage, Mr. Cool DIY 24k. The lines come precharged, as long as you don't need to alter the length, you can completely DIY it. Most people just coil up the extra line behind the unit if needed, the length of my run meant I had no extra.

It's clearly not the same quality as the non-DIY Mitsubishi and other units, but US installers barely know what mini-splits are anyway. Installing mine cost under 2k total IIRC, and the nearest quote from a pro was 5k+. Highly recommended.

Re: Home Office Projects Series: Air conditioner setup

#54

Post by gcds »

falcolas wrote: post #39
rsync wrote: 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…

All of those images look more like heat pumps, which are actually ridiculously power efficient, especially if you're heating/cooling the rooms individually (since you're cooling only the hotspots, not the entire house to handle one hot room). EDIT: The unit installed by the article's writer is an AC only, which is probably because the AC is cheaper than a heat pump. But a heat pump can both heat and cool, and are qui…

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.

Re: Home Office Projects Series: Air conditioner setup

#55

Post by marcinzm »

rsync wrote: 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…

>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.

Is it more efficient? There is going to be loss as things get pumped across hundreds of feet even with insulation. The central system needs to run even if few units or not units are using it just in case. In Asia heating and cooling is done per room to the minimum as I understand it so "per unit temperature" wouldn't fly. And an in-room gas heater is going to be 100% efficient with no losses due to transmission.

Re: Home Office Projects Series: Air conditioner setup

#56

Post by Melkman »

amluto wrote: post #43
rsync wrote: 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…

I know it's only one datapoint but recently we had four indoor airco units installed in our house for the bedrooms and livingroom. I expected a single outdoor unit. However during talks with the installer he advised us to go for two outdoor units. This was cheaper in hardware, a bit more efficient and way cheaper to install by placing one outdoor unit on the front of the house and one on the back so all rooms could be reached within a meter or so from the outdoor units.

Re: Home Office Projects Series: Air conditioner setup

#57

Post by falcolas »

gcds wrote: post #54
falcolas wrote: post #39

Earlier quoted context omitted.

All of those images look more like heat pumps, which are actually ridiculously power efficient, especially if you're heating/cooling the rooms individually (since you're cooling only the hotspots, not the entire house to handle one hot room). EDIT: The unit installed by the article's writer is an AC only, which is probably because the AC is cheaper than a heat pump. But a heat pump can both heat and cool, and are qui…

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!

Re: Home Office Projects Series: Air conditioner setup

#58

Post by rsync »

amluto wrote: post #43
rsync wrote: 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…

"This needs some real data."

I agree and I, admittedly, have none.

I will say, however, that a deeper dive into these efficiencies would also have to take into account the production, distribution and installation costs (embedded pollution, not dollars) of several hundred little devices vs. a single plant that is integrated into each unit during building construction.

Even considering room by room optimization (turning off AC in living room while you sleep, etc.) it's hard to imagine this penciling out vs. operating + embedded costs ...

(and I still suspect that just the operating costs are higher, but your point is well taken ...)

Re: Home Office Projects Series: Air conditioner setup

#59

Post by vyrotek »

dpeck wrote: post #41
7thaccount wrote: post #7

Earlier quoted context omitted.

In Louisiana and Arkansas (probably several other states), the temperature can get over 100 Farenheit with super high humidity. This leads to "swamp @$$" without copious amounts of AC. Being comfortable requires AC in the home, car, and at work. In highschool gym class we would just sit in the shade under the bleachers during the summer (too hot to do anything) and be dripping sweat everywhere back in class. It was m…

As much as A/C is amazing, it’s the lack of moving air that makes me the most uncomfortable. I’ve always been surprised at how much of Europe seems to have no interest in fans, ceiling or otherwise.

In Italy many are worried about "colpo d'aria" (blast of air) which they blame for all sorts of health problems. They also dislike ice in their drinks and think eating/swallowing some will hurt you too. I'm not certain whether the current generation of youth believe it or not.

Source: Mother is Italian.

Re: Home Office Projects Series: Air conditioner setup

#60

Post by bri3d »

pwg wrote: post #18
djanogo wrote: post #4

Where are the refrigerant lines, how did they run them from compressor to evaporator?, I thought the biggest issue with AC self install is filling the refrigerant and sealing those lines.

> Where are the refrigerant lines, how did they run them from compressor to evaporator? Look at this image from the blog post showing the post install view: https://www.techprowd.com/content/images/2020/09/image-24.pn... Notice on the left edge there is a large white "pipe" running from the evaporator unit down to a hole in the wall (the hole was already present and visible in other photos). The refrigerant lines are…

Some mini-splits (MrCool DIY series) also come with the lines precharged using quick-connects. These require no professional tools or equipment, with the drawback that installation is limited to the exact length of line provided.
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