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The far-reaching effects of air conditioning

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Re: The far-reaching effects of air conditioning

#101
post #18

Earlier quoted context omitted.

Better have it too cold and people where extra clothing than have people sweating themselves. You can always put more clothes on, you can't take off your skin.

Decreasing the AC doesn't mean people will start sweating themselves. 75 - 78 F is perfect but most buildings for some reason turn their ACs all the way down to the 60s. For athletic centers, of course it makes sense. But in big open libraries, lecture halls, places with little activity in general, it's awful. It's especially bad for your health if you live in a hot region like southern California since your body has…

Yep, in the southeastern US it's routinely so cold inside that were it to get that cold in the winter, they would turn up the heat. Except that instead of wearing three layers of clothing you're in shorts and a T-shirt because it's 95F/35C+ and 100% humidity outside.

I don't think I'll ever get used to this. I don't see how it's possible even in principle to acclimate to such large swings in temperature over such a short time frame.

Re: The far-reaching effects of air conditioning

#102

Throughout the article I was waiting for the "But.." As in some how it also deteriorated the global weather, caused some unknown sort of pollution, etc. It was good to see that Air conditioning has only improved the world and has no side-effects.

It seems nobody has mentioned a near-epidemic of respiratory system infections caused by air-conditioning. And I do not mean the cases where A/C is infected with some rare bacteria (e.g. Legionella) often causing death. Usually it is just common cold or sinusitis caused by overly chilled and dry air. I wonder what are the health-related costs of overusing A/C in moderate climate.

[deleted]

Re: The far-reaching effects of air conditioning

#103
Let's not forget about health and the breeding ground for pathogens and bacteria that AC's are.

I used to get really bad colds and coughs during summer, when the AC's went on.

I now carry a spray that puts bacteria in the air that displace other bacteria and no colds and coughs anymore. But that's not mainstream. There's probably a lot of sick people out there, thanks to AC.

Re: The far-reaching effects of air conditioning

#104
post #92

Earlier quoted context omitted.

I wonder why central cooling hasn't taken off like central heating has. It seems to me that the economy of scale would work really well with cold just as it does with heat.

In the US, centralized AC is the norm in the numerous suburban houses. Newer apartment buildings in cities have centralized AC and window units are usually only used in older buildings.

You are speaking centralized as in having one central unit for the building, are you not? I am speaking about having a big company, usually city-run, making the cool in a huge plant and then pump it out (in insulated pipes) to the rest of the city/town.

The heat version of it is very common here in Sweden (for towns bigger than, say, 10k people) and it is a lot more efficient (and therefore, cheaper) than having heating units in the different buildings. We even have bigger data centers selling their spare heat from their cooling back to the heating systems.

Re: The far-reaching effects of air conditioning

#105
post #103

Let's not forget about health and the breeding ground for pathogens and bacteria that AC's are. I used to get really bad colds and coughs during summer, when the AC's went on. I now carry a spray that puts bacteria in the air that displace other bacteria and no colds and coughs anymore. But that's not mainstream. There's probably a lot of sick people out there, thanks to AC.

> I now carry a spray that puts bacteria in the air that displace other bacteria and no colds and coughs anymore. But that's not mainstream.

No, it's not, I've never heard of it! I'm pretty skeptical of new medical claims, though, and I'm curious about this description. From my limited understanding, don't think the bacteria in air are like a bathtub full of objects that take up space, or like an ecosystem that compete for resources and reach an equilibrium: it's more like an ocean full of fish, where spraying more fish into the water aren't going to do much about the existing sharks. Can you provide a link or description of this product?

> There's probably a lot of sick people out there, thanks to AC.

This is also a claim I find surprising. Air conditioners are ubiquitous around here in the summer, but I've never heard of a health risk from them. I'm aware that the cheap window units can develop condensation puddles if improperly installed (I cleaned one out in my old apartment that was disgusting), but the typical business has central air and I thought it actually improved the microbial situation by dehumidifying the air. Citations for this claim?

Re: The far-reaching effects of air conditioning

#106

Earlier quoted context omitted.

Decreasing the AC doesn't mean people will start sweating themselves. 75 - 78 F is perfect but most buildings for some reason turn their ACs all the way down to the 60s. For athletic centers, of course it makes sense. But in big open libraries, lecture halls, places with little activity in general, it's awful. It's especially bad for your health if you live in a hot region like southern California since your body has…

I suspect it very much depends what you are used to - I probably think of 15C as "comfortable" and 25C inside would be sweltering. Having said that I'm in Scotland - the other day we had heavy rain and it was 8C which is weather we could get at any time of the year!

Wow. I think of 15C as "comfortable if I'm outside doing stuff and wearing long sleeves", but inside, it's "put the heat on (to 18C) and put on a sweater". 25C inside is what we set the air conditioning to in the summer at night so it's easier to go to sleep, but in the day, 26.5 is fine. This is in the southeastern US, and I've converted all temperatures from how I normally think of them in F.

Also, my workplace keeps inside air conditioning much cooler than I would, around 20C, which is uncomfortably cold when I'm dressed for the summer weather (ranges from 27C to 38C).

Re: The far-reaching effects of air conditioning

#107
post #99

Low-tech magazine has an article on how useful ceiling fans are: http://www.lowtechmagazine.com/2014/09/circulating-fans-air-... . They don't pollute nearly as much and work remarkably well. I live in Manhattan, which gets hot and humid in the summer, and basically never turn on my air conditioning even though I pay for my share of the building's central air conditioning. I don't need it and prefer not to cause the p…

Here in the South, ceiling fans will let you keep your AC on 80F and still be comfortable. High ceilings help, too, but they're not as common as they used to be.

Re: The far-reaching effects of air conditioning

#108
post #80

Earlier quoted context omitted.

It sounds very weird. If the space is closed, the AC makes the air dryer, so sweating should be minimal on these low temperatures (dampness is hell). Are you sitting next to a window that is blasting its rays over your body? Is the building badly designed? Are you protected by a layer of fat cells? Sweating at 24-26C without sunlight blasting at you is very anomalous. Lowering the AC to 20C or below is such an insane…

I don't disagree with you but I'm not sure all your questions are reasonable/respectful. Here are a few examples from my situation. The AC in Japan has two settings--one is cool and one is "dry" for dehumidify. The cool setting does not dry the air (or if so, ever so slightly). We have high humidity so 26 degrees can feel hot indoors. There are some seats in the office that are close enough to have the sunlight hit t…

> The AC in Japan has two settings--one is cool and one is "dry" for dehumidify. The cool setting does not dry the air (or if so, ever so slightly). We have high humidity so 26 degrees can feel hot indoors.

I'm curious how this works. In America, we have only one setting, and it does both. The indoor air is 23 degrees or so (22 in busy offices, 25 in frugal/environmentally conscious homes...28 would be considered oppressive heat, no matter the humidity). But the evaporator coils in the air handler should be cooled to about 5 degrees in a properly functioning air conditioner. If the air is humid when it cools on these coils, it drops below the dew point, and humidity condenses out of the air to be drained out of the building. If the AC is properly sized, it keeps the air indoors comfortably dehumidified (if too large, it will cool a small amount of air by a lot, and run too infrequently to dehumidify; if too small, the air temperature will not drop enough to cause condensation).

We also have dehumidifiers, which are practically identical to air conditioners but have the condenser coils in the same machine to warm the air back up before it exits (and to simplify construction/improve efficiency). These actually add a bit of heat to the room, but do dry out the air. Typically, these are only used when a home doesn't have an air conditioner.

Re: The far-reaching effects of air conditioning

#109
post #103

Let's not forget about health and the breeding ground for pathogens and bacteria that AC's are. I used to get really bad colds and coughs during summer, when the AC's went on. I now carry a spray that puts bacteria in the air that displace other bacteria and no colds and coughs anymore. But that's not mainstream. There's probably a lot of sick people out there, thanks to AC.

That's a problem with your AC unit's poor antibacterial filtration and your home's filters. Filters should be replaced every few months, if not monthly. There's also UV lamps that can be installed in AC's, or units that come with them, to sterilize the coil and air.

Re: The far-reaching effects of air conditioning

#110

Wow, it has to be 35c/95f before it is hot. Living in Australia on one mine site the daily temperature was 45c/113f at night 32 c/90f Amazing how you get used to the temperature. Joys of working in a desert in Summertime. Never use air conditioning no good for my health. And yes termites are pretty smart in keeping things cool

Humidity plays a huge role in this. In dry climates, it can be 30-40c without too much problem, you just need to hydrate a lot. If it's humid, then even 25c can be very uncomfortable.
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