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The far-reaching effects of air conditioning

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Re: The far-reaching effects of air conditioning

#161

Post by klipt »

Declanomous wrote: post #149
pavlov wrote: post #56

Earlier quoted context omitted.

Japan is further ahead, as they have optimized this with a decade-old policy called "Cool Biz". To save energy and money by reducing AC, office workers are allowed to wear more casual clothing in the summer: https://qz.com/465327/ditch-the-tie-and-reduce-the-ac-japans...

I wish we had that rule. My last 3 jobs have been in historical buildings. One didn't have AC, and the other two have barely had functional AC. My desk reaches about 80 degrees once the weather is over 65, and it won't drop below that until the fall. In order to make our AC more efficient they "weather sealed" the windows, which mostly involved gluing them shut. So now I can't open the window when it's cooler outside…

> Most of the women don't mind because they can wear light dresses and slip on shoes.

That's a classic example of female privilege: https://sindeloke.wordpress.com/2010/01/13/37/

(If the AC is too cool it's male privilege instead)

Re: The far-reaching effects of air conditioning

#162

Post by cr0sh »

rudedogg wrote: post #143

I live in an area where evaporative coolers are effective. I hate setting it up every year, and was looking into central air. When researching I learned about how efficient evaporative coolers are, and it gave me more appreciation for them. https://en.wikipedia.org/wiki/Evaporative_cooler : * Estimated cost of operation is 1/8 that of refrigerated air conditioning It's really interesting to think about the advantages…

> I wonder if the efficiency of the new design is lower than the traditional centrifugal fan design?

It depends. They each have their pros and cons:

https://en.wikipedia.org/wiki/Centrifugal_fan

http://www.pelonistechnologies.com/blog/axial-vs.-centrifuga... (might be somewhat biased)

https://en.wikipedia.org/wiki/Fan_(machine)

Unfortunately I couldn't find anything on axial fan efficiency or whatnot, compared to centrifugal fans. In general, though, if I had to pick one I'd go with the centrifugal fan for cooling purposes; they seem to move air much better than axial fans.

They do make direct-drive centrifugal fans, but I am not sure if they exist in large versions for home cooling systems. They are made for use in computers, as well as for smaller (but still large) units like blowers for drying and for things like "air curtains" and smaller blowers for small air-conditioning systems.

Re: The far-reaching effects of air conditioning

#163

Post by LeifCarrotson »

tunap wrote: post #128
LeifCarrotson wrote: post #105

Earlier quoted context omitted.

> 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 compe…

As to your 2nd point, go find your indoor blower(furnace closet for split system or outside in a package unit), pull the power supply , then open and take a look inside at the blower wheel. Unless the unit is a less than a year old you will will clearly observe why health risks do exist. If you need more proof see the evap coil & the primordial sludge in the condensate tray/drain. When finished, reassemble, plug powe…

I clean out my evap coils and condenser coils annually, and replace my filter twice a year (for efficiency, not for health). I'm well aware of the dust that my filter removes, which makes my indoor air cleaner than outdoor air. My allergen-sensitive wife proves experimentally that it has a strong positive effect for a couple weeks every spring and fall. And I'm aware of the crud that develops in the condensate tray. There's little crud in my central air system, but when I used a window AC in an apartment and the unit wasn't leveled properly it got pretty bad.

More generally, though, the presence of unattractive substances does not imply a health risk. My yard is, in the most basic sense, an enormous pile of dust, plus a few organics that grow and decay into dust. My home happens to be a few hundred meters from a lovely trout stream, and that stream and its floodplain contain more life from bacteria to algae to fish than any primordial sludge ever had. Neither are dangerous.

Re: The far-reaching effects of air conditioning

#164

Post by LeifCarrotson »

nerdshoe wrote: post #112
LeifCarrotson wrote: post #105

Earlier quoted context omitted.

> 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 compe…

Legionnaire's disease thrives in air conditioners https://en.wikipedia.org/wiki/Legionnaires%27_disease

There's little risk of disease (Specifically, Legionnaires') from residential air-cooled A/C systems. The risk is typically from industrial air conditioning systems which use a water-based heat exchanger between a radiator system on the roof and the condenser. The water in this system is kept warm. The water in the condensate tray of a typical AC is cold and continually drained, so the disease doesn't propagate well.

Re: The far-reaching effects of air conditioning

#165

Post by Declanomous »

klipt wrote: post #161
Declanomous wrote: post #149

Earlier quoted context omitted.

I wish we had that rule. My last 3 jobs have been in historical buildings. One didn't have AC, and the other two have barely had functional AC. My desk reaches about 80 degrees once the weather is over 65, and it won't drop below that until the fall. In order to make our AC more efficient they "weather sealed" the windows, which mostly involved gluing them shut. So now I can't open the window when it's cooler outside…

> Most of the women don't mind because they can wear light dresses and slip on shoes. That's a classic example of female privilege: https://sindeloke.wordpress.com/2010/01/13/37/ (If the AC is too cool it's male privilege instead)

That article was far more sensible and pertinent than I was expecting. Especially relevant, given the fact that a couple weeks ago one of my coworkers was wearing a jacket while I was sweating though my clothes.

Our handbook is pretty terrible to both sexes though. There's two full pages on how women should do their makeup. It can basically be summed up as "You need to wear makeup, but don't look like a whore." So, at least I don't have to deal with that.

Honestly, I wouldn't complain if it didn't affect my work, but when it gets this hot I get dizzy unless I drink water like it is going out of style, which means I have to get up to fill my water and relieve myself. And even then I can barely concentrate.

I still blame the dress code more than anything. I'm comfortable to above 90 degrees or so if I'm wearing shorts and a lightweight tee. Slacks, leather shoes and a long sleeve shirt are not suitable much above 75 as far as I'm concerned.

Re: The far-reaching effects of air conditioning

#166

Post by Declanomous »

dalbasal wrote: post #159
Declanomous wrote: post #149

Earlier quoted context omitted.

I wish we had that rule. My last 3 jobs have been in historical buildings. One didn't have AC, and the other two have barely had functional AC. My desk reaches about 80 degrees once the weather is over 65, and it won't drop below that until the fall. In order to make our AC more efficient they "weather sealed" the windows, which mostly involved gluing them shut. So now I can't open the window when it's cooler outside…

You shouldn't have left Ireland.

Welcome to the continental climate, where it gets very cold in the winter and very hot and humid in the summer.

Re: The far-reaching effects of air conditioning

#167

Post by SeoxyS »

Hydraulix989 wrote: post #19
SeoxyS wrote: post #15

Earlier quoted context omitted.

I went to HK in the middle of hottest times (Aug 1st) last year and it was absolutely brutal. But then again, the entire city really grew out of nowhere during the past century, so it kind of grew in tandem with air conditioning. HK is one of those places that's absolutely amazing as a city, and has some of the worst weather on earth (crazy humidity all the time, insane heat in summer, crazy rains and typhoons all th…

I really liked the weather there when I went in December.

And I really liked the air quality when I was in Beijing two weeks ago. But that was a fluke. Most of the times, things aren't as rosy.

Re: The far-reaching effects of air conditioning

#168

Post by LeifCarrotson »

hueving wrote: post #69
ishi wrote: post #8

The downside of air conditioned homes is that houses are now built with very little regard to insulation and intelligent use of the sun (to warm the house at winter) and the wind (to cool it during summertime). My house has a large, paper-thin southern wall and during the summer it gets so hot that it radiates heat into the house at night. So I have to air-condition my bedroom at night. And the windows are stupidly d…

Where was your house built where energy wasn't a concern? In the US, nearly all regions will get a cold winter or a really hot summer and nobody likes $300/mo utility bills so efficiency is still a concern.

It's not where, but when. I worked with a very knowledgeable realtor a few years ago when buying my house. He described (and we observed) a series of trends.

Older houses (in my area, that's early 1900s, laugh away you European readers) were built with huge beams of old-growth timber by careful craftsmen (sometimes in the Craftsman style, sometimes colonial or victorian). Houses this old typically had antique plumbing and electrical service, which needed (or now really need) upgrades, and they also will likely need window and/or siding replacement. During these repairs and remodels, smart homeowners and contractors also upgrade the energy efficiency, and there's a very strong skeleton on which to do so.

Shortly after WWII, there was a lumber shortage. You can drive around and identify the neighborhoods which were constructed in the late 40s and early 50s because the eaves only project a few inches out from the walls. These were built as fast and cheaply as possible. But for a while, energy - especially for heat - was cheap, so they kept building them.

Since then, energy has become variously more and less expensive, and manufacturing/construction techniques have produced cycles of lower quality cookie-cutter cost-optimized goods and higher-quality standardized, well engineered construction. We're riding high on an efficiency swing right now, to the point of absurdities like homes so well air-sealed between Tyvek, caulk, and air-tight electrical fixtures that you're required to install an air vent to the outdoors in the furnace room to prevent negative pressure problems.

Re: The far-reaching effects of air conditioning

#169

Post by antisthenes »

Declanomous wrote: post #165
klipt wrote: post #161

Earlier quoted context omitted.

> Most of the women don't mind because they can wear light dresses and slip on shoes. That's a classic example of female privilege: https://sindeloke.wordpress.com/2010/01/13/37/ (If the AC is too cool it's male privilege instead)

That article was far more sensible and pertinent than I was expecting. Especially relevant, given the fact that a couple weeks ago one of my coworkers was wearing a jacket while I was sweating though my clothes. Our handbook is pretty terrible to both sexes though. There's two full pages on how women should do their makeup. It can basically be summed up as "You need to wear makeup, but don't look like a whore." So, a…

> I'm comfortable to above 90 degrees

Consider yourself lucky.

I am not comfortable in temperatures above 80 in any clothing bar undergarments, especially not if you want me to be productive cognitively in any way.

And if you add humidity on top of that, it essentially reduces me to a vegetable, unable to do anything but take short naps and cold showers every few hours.

Re: The far-reaching effects of air conditioning

#170

Post by sqeaky »

ZeroGravitas wrote: post #89
eBombzor wrote: post #25

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…

They may have the issue of only having one thermostat for the whole building. They then have to balance the demands of the people in the coldest part of the building and those in the warmest part of the building. If the system isn't well designed, those could be tricky to reconcile.

I would argue that if there isn't one thermostat per section or even per room, that the building is poorly designed.
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