WEBVTT - Air Conditioners 0:00:00.280 --> 0:00:02.960 Brought to you by the reinvented two thousand twelve Camray. 0:00:03.160 --> 0:00:08.880 It's ready. Are you get in touch with technology? With 0:00:09.000 --> 0:00:17.760 tech Stuff from how stuff works dot com. Hello again, everyone, 0:00:17.760 --> 0:00:20.040 Welcome to tech Stuff. My name is Chris Poette and 0:00:20.040 --> 0:00:22.880 I'm an editor at how stuff works dot com. Sitting 0:00:22.920 --> 0:00:27.240 across from me is usual is senior writer Jonathan Strickland Hottown, 0:00:27.440 --> 0:00:30.040 Summer in the city, back in my neck, getting dirty 0:00:30.080 --> 0:00:34.880 and gritty. That was an interesting choice for this episode. 0:00:34.880 --> 0:00:36.920 A little love and spoonful for you guys out there. 0:00:37.000 --> 0:00:40.120 All right. Then, we actually have a little bit of 0:00:40.159 --> 0:00:42.680 business to get to before we jump right into the topic, 0:00:42.760 --> 0:00:51.560 and that is some listener mail. This listener mail comes 0:00:51.560 --> 0:00:54.360 from Ted, and Ted says, I'm a regular listener of 0:00:54.360 --> 0:00:56.840 the podcast and it's been great to listen to on 0:00:56.920 --> 0:00:59.040 my commute to and from my co op this summer. 0:00:59.280 --> 0:01:02.360 I'd like to hear about how air conditioning HVAC units work. 0:01:02.560 --> 0:01:04.440 We design and build them, among other things that my 0:01:04.480 --> 0:01:06.880 co op company, and after helping to put one together 0:01:06.920 --> 0:01:09.119 and tested, I'm still not clear on how it works. 0:01:09.280 --> 0:01:11.840 I would also appreciate an episode about how capacitors work 0:01:11.840 --> 0:01:13.959 in circuits. As a supplement to the article on the 0:01:13.959 --> 0:01:16.559 How Stuff Works site. Lastly, could you talk about Google 0:01:16.560 --> 0:01:18.679 Plus as well as Windows eight. Thanks a lot, keep 0:01:18.720 --> 0:01:21.399 up the good work and good jokes. Ted, Well, Ted, 0:01:21.560 --> 0:01:24.119 We're gonna talk about air conditioners today. But stick around 0:01:24.120 --> 0:01:26.760 because right after we record this, we're recording our episode 0:01:26.800 --> 0:01:29.600 about Google Plus. Yeah, because you know, a couple of 0:01:29.600 --> 0:01:31.399 people have asked for that. Yeah, you'll like a couple, 0:01:31.480 --> 0:01:34.560 I mean, you know. And I plan on scheduling the 0:01:34.600 --> 0:01:38.880 Google Plus episode to publish immediately after this one. So 0:01:39.040 --> 0:01:41.399 if this published on a Monday, look for it on Wednesday. 0:01:41.440 --> 0:01:43.880 If it published on Wednesday, look for it next Monday. 0:01:43.920 --> 0:01:45.920 All right then, because I don't have the calendar in 0:01:45.920 --> 0:01:48.440 front of me. But we're gonna talk about air conditioning units. 0:01:48.480 --> 0:01:50.520 We're not actually gonna talk about h VAC units today. 0:01:50.520 --> 0:01:53.400 We're just gonna talk about air conditioners because there's a 0:01:53.440 --> 0:01:55.400 bit to them. Yeah, there's a bit to them. And 0:01:55.480 --> 0:01:59.040 it's also we in Atlanta right now are in the 0:01:59.040 --> 0:02:01.960 middle of a pretty nasty heat wave. It actually kind 0:02:02.040 --> 0:02:04.520 of broke a little bit. We we have a little 0:02:04.520 --> 0:02:06.920 bit of a break in it right now. It's today, Yeah, 0:02:06.920 --> 0:02:08.920 it's in the it's just it's only in the upper 0:02:09.000 --> 0:02:12.000 eighties with a heat index in the mid nineties today. Yeah, 0:02:12.240 --> 0:02:14.440 but recently we had a heat index over a hundred 0:02:14.440 --> 0:02:17.880 and seven degrees and really high humidity. So in Atlanta 0:02:17.960 --> 0:02:20.519 that was pretty miserable, and a lot of the United 0:02:20.520 --> 0:02:22.320 States has been going through the same thing. This is, 0:02:22.360 --> 0:02:24.960 of course the summer of two thousand eleven from for 0:02:25.040 --> 0:02:27.600 all of you people who are from the future. Uh 0:02:28.000 --> 0:02:32.040 So we thought, you know what, we really appreciate air conditioning, 0:02:32.120 --> 0:02:36.720 So let's talk about how air conditioners work. Yeah, I actually, uh, 0:02:36.760 --> 0:02:40.040 I actually am very grateful for the air conditioning, especially 0:02:40.080 --> 0:02:43.560 this last week. But um. The the answer to to 0:02:43.639 --> 0:02:46.680 the question though, how air conditioners work is sort of 0:02:47.360 --> 0:02:49.400 It's not an easy one because there are different kinds 0:02:49.400 --> 0:02:53.880 of air conditioning. Yeah. Yeah, it's all based on heat exchange, 0:02:54.040 --> 0:02:57.000 but the method of heat exchange differs from one to 0:02:57.080 --> 0:02:59.560 the other, although I would say the majority of them 0:03:00.400 --> 0:03:03.920 use the refrigerant method of heat exchange, where you're compressing 0:03:03.960 --> 0:03:08.600 a liquid and then you are allowing it to boil off. Um. 0:03:08.960 --> 0:03:11.800 But that's a pretty complex issue. Did you want to 0:03:11.840 --> 0:03:14.360 talk about the other types really quickly or should I 0:03:14.400 --> 0:03:17.480 just launch into a science lesson. Well, I think it 0:03:17.560 --> 0:03:19.320 might be a good idea to go ahead and talk 0:03:19.320 --> 0:03:21.799 about the type of air conditioning that most of us use, 0:03:21.840 --> 0:03:24.280 and then maybe look at some of the others. Um. 0:03:24.400 --> 0:03:26.799 I do want to mention a name that is familiar 0:03:26.840 --> 0:03:28.000 to a lot of us, at least here in the 0:03:28.040 --> 0:03:31.920 United States. That would be Willis Carrier. You might say, 0:03:32.040 --> 0:03:33.880 you know, I don't know who that is, Like, oh, wait, 0:03:34.280 --> 0:03:37.480 Carrier made air conditioners. Well he Uh, this was in 0:03:37.520 --> 0:03:41.320 the early twentieth century, so really the modern electrical air conditioner. 0:03:41.360 --> 0:03:45.440 Of course, electricity not being that prevalent until um, you know, 0:03:45.480 --> 0:03:49.800 the late eight hundreds, early nineteen hundreds. UM. Carrier lived 0:03:49.800 --> 0:03:52.720 in Buffalo, New York in the United States, and UM 0:03:52.960 --> 0:03:55.840 he came up with the idea of the do point control, 0:03:56.080 --> 0:04:00.120 which is an air conditioning UH system that basically the 0:04:00.960 --> 0:04:05.240 UH had to do with UH the saturation of cool 0:04:05.360 --> 0:04:08.840 air and UH which you know loses moisture through condensation. 0:04:09.000 --> 0:04:12.040 And that's your science lesson, isn't it. Yeah. Yeah, we're 0:04:12.040 --> 0:04:20.559 gonna have to talk about the relationship between pressure, temperature, liquids, gases, UH, 0:04:20.640 --> 0:04:24.000 and and the It's important to understand this this basic 0:04:24.080 --> 0:04:26.520 level of science in order to really get a grip 0:04:26.560 --> 0:04:29.360 on what an air conditioner is doing, because otherwise I 0:04:29.600 --> 0:04:31.400 could talk about what an air conditioner is doing, but 0:04:31.440 --> 0:04:34.120 you would say, well, why does that work? I know 0:04:34.200 --> 0:04:36.279 how it works, but why does it work? Yeah, we 0:04:36.320 --> 0:04:39.320 do have an article on the side about that, of course. Yeah. 0:04:39.480 --> 0:04:42.120 Actually we have a great article on how air conditioners work, 0:04:42.160 --> 0:04:43.960 and that one was written by Marshall Brain, who was 0:04:44.000 --> 0:04:46.280 the founder of how stuff works dot com. So this 0:04:46.360 --> 0:04:48.560 is it's one of our flagship articles. If you really 0:04:48.560 --> 0:04:51.720 want to see some good animations and illustrations about it, 0:04:51.760 --> 0:04:55.160 I recommend checking that out. But we're gonna talk first 0:04:55.200 --> 0:05:00.599 about well, some basic matter. So we know that matter 0:05:00.720 --> 0:05:03.800 is made up of teeny tiny particles, Yes, you know, 0:05:03.880 --> 0:05:08.800 atoms and molecules. Right, So with solids, this these particles 0:05:08.839 --> 0:05:13.239 are they're not really truly stationary. Okay, these are particles 0:05:13.279 --> 0:05:16.080 are always moving, but in in solids, they're not moving 0:05:16.080 --> 0:05:19.000 a lot, right, Yeah, they're packed closely together. Yeah, they're 0:05:19.080 --> 0:05:21.960 very very dense, and that's why we think of them 0:05:22.000 --> 0:05:26.080 as solid and liquids, not that dense and liquids. Uh, 0:05:26.160 --> 0:05:28.800 they are these particles are allowed to move around, and 0:05:28.839 --> 0:05:31.200 they move around in a more or less random fashion. 0:05:31.760 --> 0:05:33.800 For all we know, it could be a very orderly fashion. 0:05:33.880 --> 0:05:36.640 But it's so orderly, it's like such a complex system 0:05:36.640 --> 0:05:39.159 that we're unable to understand it. So to us, we 0:05:39.240 --> 0:05:41.600 might as well say random. Yeah, well, there's one molecule 0:05:41.600 --> 0:05:44.640 on the side, going okay, keeping keeping mindone, if you 0:05:44.720 --> 0:05:46.720 if you look really closely, you'll see one with those 0:05:46.760 --> 0:05:49.520 little uh those little cones that air track, you know, 0:05:49.880 --> 0:05:52.240 the people on the tar mac use, and they're like, 0:05:52.320 --> 0:05:54.880 all right, coming in, go to the left. It's very 0:05:54.920 --> 0:05:57.560 hard to hold those with your electrons. Yeah, and that's 0:05:57.560 --> 0:05:59.960 why that's why you hardly ever see them. Also, it's 0:06:00.000 --> 0:06:01.760 impossible to know where they are at any one time 0:06:01.760 --> 0:06:05.800 because the uncertainty principle. Uh wow, we're getting really kind 0:06:05.800 --> 0:06:08.480 of crazy with our humor today. So anyway, all right, 0:06:08.520 --> 0:06:11.760 let's let's get serious. So in liquid, these particles move 0:06:11.800 --> 0:06:15.080 around more or less randomly, and some of these particles 0:06:15.120 --> 0:06:18.839 are moving around with with enough energy to break free 0:06:19.040 --> 0:06:23.000 of the surface of that liquid, so they will actually 0:06:23.080 --> 0:06:27.960 become a particle that is in a vapor above that liquid, right, 0:06:28.279 --> 0:06:31.039 all right, like water that evaporates and turns into water 0:06:31.120 --> 0:06:33.520 vapor sort of. But I mean more like water that's 0:06:33.560 --> 0:06:36.880 boiling off. But yes, um, yeah, so the I was 0:06:36.880 --> 0:06:39.640 trying to go for an image that people could Yes, yes, 0:06:39.760 --> 0:06:43.040 very much, very much. So. So the way the way 0:06:43.080 --> 0:06:44.680 you would get one of these particles to do that, 0:06:44.720 --> 0:06:46.760 To get enough energy to break freeze, you have to 0:06:46.800 --> 0:06:51.240 add energy into the system, right. So you when you 0:06:51.279 --> 0:06:55.159 add energy into the system, these particles get more well, 0:06:55.360 --> 0:06:57.360 they get more energy, they start moving around more, and 0:06:57.400 --> 0:06:59.679 then they have they may have enough energy to break 0:06:59.680 --> 0:07:03.320 free from the surface. So if you add heat, that's 0:07:03.360 --> 0:07:06.159 a form of energy, like the boiling water. Right, So 0:07:06.200 --> 0:07:08.919 if you start adding heat to a liquid, more of 0:07:08.920 --> 0:07:12.520 these particles will gain energy and be able to escape 0:07:12.720 --> 0:07:16.360 the surface of that liquid. If you get enough vapor 0:07:16.560 --> 0:07:22.560 so that it actually equals the atmospheric pressure that's on 0:07:22.640 --> 0:07:25.960 top of that liquid, that's when you hit the boiling point. Okay, 0:07:26.000 --> 0:07:28.840 all right, So let's say you've got a pot of 0:07:28.840 --> 0:07:33.520 water at sea level. All right, Now, boiling temperature for 0:07:33.560 --> 0:07:35.160 a pot of water at sea level is two d 0:07:35.280 --> 0:07:37.160 and twelve degrees. Now, what that means is that when 0:07:37.160 --> 0:07:39.840 the water reaches two h twelve degrees, the particles in 0:07:39.840 --> 0:07:42.880 that water have enough energy to escape the surface of 0:07:42.920 --> 0:07:47.600 the water, and the vapor pressure is equal to atmospheric pressure, 0:07:47.640 --> 0:07:50.160 the water will boil and the water will not get 0:07:50.200 --> 0:07:52.800 any warmer than two twelve degrees. You could have that 0:07:52.840 --> 0:07:55.880 fire pumped up as high as it's gonna go, but 0:07:55.960 --> 0:07:58.480 the water temperature will be two hwelve degrees as it's 0:07:58.480 --> 0:08:01.480 boiling off. Now, once the water is boiled off, if 0:08:01.480 --> 0:08:03.720 you have a thermometer in that pot, the thermometer is 0:08:03.720 --> 0:08:06.800 gonna skyrocket, you know, at that point. But the temperature 0:08:06.840 --> 0:08:08.760 the water itself will remain to her and twelve because 0:08:08.800 --> 0:08:13.720 it's actually converting from liquid into gas. So that boiling 0:08:13.760 --> 0:08:16.840 point is in is important to remember. It's it's when, 0:08:16.960 --> 0:08:19.920 like I said, when the pressure of that vapor has 0:08:20.040 --> 0:08:23.880 uh equaled the atmospheric pressure of the environment around it. 0:08:23.960 --> 0:08:27.760 So if you change the atmospheric pressure around that liquid, 0:08:28.000 --> 0:08:32.200 you change the boiling point. So if if the pressure 0:08:32.440 --> 0:08:35.280 is if there's less pressure then it would be at 0:08:35.360 --> 0:08:38.280 sea level, then it's going to take a lower temperature 0:08:38.320 --> 0:08:41.920 to make that water boil. If there is more pressure 0:08:42.120 --> 0:08:44.760 then there is at sea level, then it's going to 0:08:44.800 --> 0:08:49.080 take a higher temperature to make that water boil. All right, 0:08:49.120 --> 0:08:51.760 So let's say that we have put a lid on 0:08:51.880 --> 0:08:54.360 top of that pot. Okay, by putting the lid on 0:08:54.400 --> 0:08:56.960 top of that pot, we have decreased the air pressure 0:08:57.520 --> 0:09:00.280 or the atmospheric pressure on that liquid, so the water 0:09:00.320 --> 0:09:03.880 will boil faster. All right. If you take the lid off, 0:09:03.920 --> 0:09:07.560 then you have just increased the atmospheric pressure. Because now 0:09:07.679 --> 0:09:10.440 more air is actually pressing down that liquid. It's going 0:09:10.679 --> 0:09:15.160 to actually increase the boiling point to its normal boiling 0:09:15.200 --> 0:09:19.079 point at that particular environment. So now we've talked about 0:09:19.120 --> 0:09:24.080 how you have increased pressure, you've increased the temperature of 0:09:24.120 --> 0:09:27.679 the boiling point. Now that's the basics for what we're 0:09:27.679 --> 0:09:31.040 going to talk about with air conditioners. Because air conditioners 0:09:31.040 --> 0:09:34.640 are at least the typical ones you find in houses 0:09:34.679 --> 0:09:41.240 and buildings, use pressure to use to create a pressurized 0:09:41.280 --> 0:09:45.000 liquid that then turns into a depressurized gas. And it's 0:09:45.000 --> 0:09:47.880 a closed loop system. And the liquid in this case 0:09:48.000 --> 0:09:51.720 is a refrigerant, right, so it tends to be some 0:09:51.800 --> 0:09:56.880 sort of of of material that has a boiling point 0:09:57.360 --> 0:09:59.920 that is pretty low. Like it doesn't it's not a 0:10:00.080 --> 0:10:04.480 very high temperature in other words, in normal conditions, normal 0:10:04.520 --> 0:10:08.600 being like in everyday atmospheric conditions that would be a gas. Right. 0:10:09.840 --> 0:10:12.800 So in the one of the common ones we talked 0:10:12.800 --> 0:10:15.320 about is free on, which at this point is more 0:10:15.360 --> 0:10:18.760 or less a generic term, kind of like Xerox or Kleenex. 0:10:18.760 --> 0:10:20.960 Would you know those companies would argue they are not 0:10:21.000 --> 0:10:24.280 generic terms. Yes, they would argue. Their lawyers would argue, yes, certainly. 0:10:24.400 --> 0:10:27.600 But but people use effectively use them, right right, So, 0:10:27.720 --> 0:10:29.880 like I said, I'm going to xerox this, you're you 0:10:30.000 --> 0:10:31.920 talk about, you're making a copy of it, or I'm 0:10:31.960 --> 0:10:34.040 going to Google this. In that case, you may be 0:10:34.080 --> 0:10:36.240 actually using Google, or you may just be using some 0:10:36.280 --> 0:10:39.240 search engine. Kind of the same thing. When people talk 0:10:39.240 --> 0:10:42.360 about free on, unless they're spit talking about the specific 0:10:42.559 --> 0:10:46.760 uh refrigerant, it's more or less just refrigerants in general. Yeah, 0:10:46.760 --> 0:10:50.600 based on my experience recently, I haven't seen the actual 0:10:50.880 --> 0:10:54.080 product free on in quite some time. I think for 0:10:54.480 --> 0:11:00.439 concerns of cfcslora flora carbons. Yes, Um, so I that 0:11:00.440 --> 0:11:03.520 that these days, I don't think free on is used 0:11:03.600 --> 0:11:05.640 very much, if at all, at least not in the 0:11:05.720 --> 0:11:08.800 United States. Um. Of course I could be wrong, but 0:11:09.520 --> 0:11:13.120 there are other refrigerants too, so right, so what an 0:11:13.120 --> 0:11:16.080 air cons what an air condissuer does, is it? It 0:11:16.160 --> 0:11:19.760 pressurizes this refrigerant in one section. Think of think of 0:11:19.800 --> 0:11:23.040 the air conditioner as a closed loop system that has 0:11:23.080 --> 0:11:26.520 a low pressure section and a high pressure section. All right, 0:11:26.840 --> 0:11:30.160 the and the guardians of this, you know, the two 0:11:30.240 --> 0:11:33.480 elements that that separate the low pressure from the high 0:11:33.520 --> 0:11:36.520 pressure are a compressor on one end of the loop 0:11:37.440 --> 0:11:40.559 and a valve on the other end of the loop 0:11:40.600 --> 0:11:43.400 and expansion valve on the other end of the loop. 0:11:43.720 --> 0:11:47.000 These two act as the gateway that keep the pressure 0:11:47.080 --> 0:11:50.920 high on one side and low on the other. All right, 0:11:51.720 --> 0:11:54.480 And it's hot on one side and cool on the other, yes, exactly. 0:11:54.480 --> 0:11:59.200 Because as we pressurize the the refrigerant, the temperature of 0:11:59.280 --> 0:12:04.640 that refrigerant goes up, all right. So the refrigerant, normally 0:12:04.720 --> 0:12:08.080 at at room temperature, would be a gas. You use 0:12:08.280 --> 0:12:11.720 the compressor to compress this gas to a point where 0:12:11.720 --> 0:12:14.040 it's very very dense, and then you run it through 0:12:14.200 --> 0:12:19.439 a series of coils that allow the the this high 0:12:19.480 --> 0:12:22.880 temperature pressurized gas to give off a lot of heat. 0:12:23.480 --> 0:12:27.280 The heat escapes into the ambient. Uh well, that the 0:12:27.400 --> 0:12:30.400 environmental atmosphere. So what the atmosphere has to be of 0:12:30.440 --> 0:12:34.600 a cooler temperature than the the pressurized gas. Right For, 0:12:34.679 --> 0:12:36.480 in order for heat to transfer, it has to go 0:12:36.520 --> 0:12:38.520 from high heat to low heat. You can't have something 0:12:38.559 --> 0:12:41.199 go low heat to high heat. So, in other words, 0:12:41.240 --> 0:12:43.960 if I were to turn on my air conditioner and 0:12:44.000 --> 0:12:48.400 I happened to be in an incredibly hot environment, let's 0:12:48.440 --> 0:12:51.360 say that for argument's sake, it's a hundred and sixty 0:12:51.360 --> 0:12:56.280 degrees outside and my pressurized refrigerant only gets up to 0:12:56.320 --> 0:12:58.800 a temperature of a hundred and forty degrees, that air 0:12:58.840 --> 0:13:01.640 conditioner is not going to work because you are not 0:13:01.720 --> 0:13:05.520 going to have any heat exchange from the actually I'll 0:13:05.559 --> 0:13:07.800 have the wrong sort of heat exchange, but you're not 0:13:07.840 --> 0:13:10.960 gonna have any heat released from the refrigerant into the 0:13:10.960 --> 0:13:13.880 atmosphere because the atmosphere is actually warmer than the refrigerant 0:13:14.080 --> 0:13:18.280 even at its pressurized state. All right, So you've got 0:13:18.320 --> 0:13:23.000 these coils that this heated gas, this compressed heated gas 0:13:23.120 --> 0:13:25.640 is moving through. As it moves through the coils and 0:13:25.679 --> 0:13:28.800 starts to release heat into the atmosphere, that means the 0:13:28.840 --> 0:13:34.240 gas cools. Well. As gas cools, it condenses, and this 0:13:34.320 --> 0:13:38.000 is the process where a gas converts back into a liquid. 0:13:38.480 --> 0:13:41.439 Now it's going to be at a liquid at a 0:13:41.520 --> 0:13:45.040 higher temperature than normally would be because it's under pressure. 0:13:45.280 --> 0:13:47.360 You know, we talked about that the higher the pressure, 0:13:47.440 --> 0:13:49.400 the higher the boiling point. So once you get that 0:13:49.400 --> 0:13:53.840 temperature down below the boiling point of that pressurized substance, 0:13:54.200 --> 0:13:57.120 it condenses into a liquid. This is how we get 0:13:57.160 --> 0:14:02.079 things like liquid liquid hydrogen, with oxygen liquid nitrogen. You 0:14:02.120 --> 0:14:07.800 compress these gases to a very condensed state, compressed state, 0:14:07.840 --> 0:14:10.679 i should say, and it condenses into a liquid, and 0:14:10.840 --> 0:14:12.520 as long as you keep it under pressure, it will 0:14:12.520 --> 0:14:15.120 stay a liquid. If you release that pressure, then it 0:14:15.200 --> 0:14:19.360 immediately starts to boil off and convert into a gas. Well, 0:14:19.360 --> 0:14:22.800 that's the secret. That's the secret of the the valve 0:14:22.880 --> 0:14:25.520 at the end of this loop um the expansion valve, 0:14:25.600 --> 0:14:30.680 because once it the pressurized gas gets to the expansion valve, 0:14:31.000 --> 0:14:34.080 that's what allows it to move into the low pressure 0:14:34.160 --> 0:14:38.720 system and it immediately begins to boil off and essentially 0:14:38.720 --> 0:14:41.680 starts absorbing heat from the environment. Just as it was 0:14:41.920 --> 0:14:46.240 releasing heat when it was going through the condenser coils, 0:14:46.280 --> 0:14:50.239 now it's it's absorbing heat, which means that the surrounding 0:14:50.280 --> 0:14:53.600 air loses heat. It transfers the heat from the air 0:14:53.720 --> 0:14:58.760 into this boiling liquid that's becoming gas very very quickly, 0:14:59.400 --> 0:15:03.040 and then the surrounding air is cooled. That's the basis 0:15:03.040 --> 0:15:07.120 of an air conditioner. Yes, we can actually walk through 0:15:07.160 --> 0:15:10.440 those phases and go into more detail now, but that 0:15:10.440 --> 0:15:13.920 that's basically how it works. It's all about, really you 0:15:13.920 --> 0:15:16.120 have two closed systems. You have the closed system of 0:15:16.160 --> 0:15:18.960 the refrigerant and then you have the closed system of 0:15:19.000 --> 0:15:22.560 the air inside whatever it is you're you're cooling. Because 0:15:22.600 --> 0:15:25.640 you're not pulling air in from the outside environment and 0:15:25.640 --> 0:15:28.480 then cooling it and then pushing it into the building. 0:15:28.760 --> 0:15:31.720 You're recycling the air that's inside the building and it's 0:15:31.840 --> 0:15:35.000 cooling it through the bye bye this heat exchange method 0:15:36.640 --> 0:15:38.880 and just a little bit of h v A C. 0:15:39.160 --> 0:15:44.440 Some systems can reverse it works, and that's called a 0:15:44.480 --> 0:15:46.240 heat pump. I have one on my house, is a 0:15:46.280 --> 0:15:50.400 matter of fact um, which is very convenient. Right In 0:15:50.400 --> 0:15:53.040 that case, you're you're doing the same system, except you're 0:15:53.160 --> 0:15:57.440 you're reversing the process. Essentially, you're recycling the warm air 0:15:57.480 --> 0:15:59.920 inside your house and it's warming it instead of cool 0:16:00.080 --> 0:16:03.800 it YEA and injecting the cooler air outside from the 0:16:03.800 --> 0:16:06.760 process that actually takes place in the unit itself outside 0:16:07.240 --> 0:16:10.760 because if you've ever been outside and next to an 0:16:10.800 --> 0:16:14.520 air conditioner, you've felt you know, it blows hot air outside, 0:16:14.560 --> 0:16:17.560 So you know that, but that's not coming from inside 0:16:17.560 --> 0:16:21.640 the house. That is the result of the process, um, 0:16:21.720 --> 0:16:25.360 and the the exchange of heat. Now, UM Carrier actually 0:16:25.400 --> 0:16:28.240 came up with a system for buildings. He installed one 0:16:28.400 --> 0:16:34.320 in at Grahman's Metropolitan Theater in l a Man's Chinese Theater. Yes, 0:16:34.520 --> 0:16:38.440 I've been there, UM saw the Matrix sequel. It was terrible. 0:16:38.720 --> 0:16:42.920 Theater was great. It was terrible. UM. Yeah. And at 0:16:42.960 --> 0:16:47.520 that point air conditioning was used to uh feed air 0:16:48.160 --> 0:16:50.800 or take air in the ceiling and put it out 0:16:50.840 --> 0:16:52.680 at the floor level, which would be you know, useful 0:16:52.720 --> 0:16:54.480 because the hotter air would be toward the top of 0:16:54.520 --> 0:16:58.520 the room. Um. And the first fully air conditioned office building, 0:16:58.560 --> 0:17:03.440 according to Britannica, was the MILEM Building or MILAM. I 0:17:03.480 --> 0:17:06.960 don't know, it's like M I L A M in 0:17:07.000 --> 0:17:09.600 San Antonio in the United States, and that was built 0:17:09.600 --> 0:17:13.840 in the late nineteen twenties. UM. So again you know, 0:17:13.880 --> 0:17:17.199 this hasn't been forever and ever, but there uh you know, 0:17:17.359 --> 0:17:20.040 it's certainly something that we use and a lot of 0:17:20.040 --> 0:17:23.840 the buildings here down south, especially in these states. But 0:17:23.880 --> 0:17:26.119 there are many, many other types of air conditioning that 0:17:26.160 --> 0:17:28.000 have been going on for years. Do you want to 0:17:28.000 --> 0:17:29.719 get into those yet or do you want to go 0:17:29.760 --> 0:17:31.840 back and get more into the process. Let me, let 0:17:31.880 --> 0:17:34.120 me get more into the process of the typical air conditioner, 0:17:34.200 --> 0:17:36.919 because this is what's going to apply, I think to 0:17:36.920 --> 0:17:40.280 the majority of our listeners who have air conditioning. Yeah, 0:17:40.359 --> 0:17:43.160 so so, and then we can talk about the other kinds, 0:17:43.160 --> 0:17:47.480 including uh, my favorite, the swamp cooler. We'll get into that. 0:17:47.760 --> 0:17:52.719 So let's let's break this down further about the parts 0:17:52.840 --> 0:17:55.280 of an air conditioner. So you've got usually typically of 0:17:55.320 --> 0:18:00.480 an electric motor, and the electric motor you turn earns 0:18:00.560 --> 0:18:04.000 a piston. This this is a very simple compressor. This 0:18:04.080 --> 0:18:07.280 is like the simplest form of a compressor. So not 0:18:07.359 --> 0:18:09.920 all air conditioner compressors are like this, but this, this 0:18:10.000 --> 0:18:14.000 demonstrates the principle. Uh you would call this a piston 0:18:14.080 --> 0:18:17.879 compressor or a reciprocating compressor. So imagine that you have 0:18:18.080 --> 0:18:21.520 a chamber, all right, so a cylinder, let's say, and 0:18:21.600 --> 0:18:24.640 inside the cylinder you have a piston that can move 0:18:24.840 --> 0:18:28.119 up and down the chamber which is sealed, and you 0:18:28.359 --> 0:18:30.879 the electric motor makes the piston go up and down. 0:18:31.240 --> 0:18:35.160 Now at the bottom of this chamber, you have two valves. 0:18:36.160 --> 0:18:38.920 You have a an intake or suction valve that will 0:18:38.960 --> 0:18:43.359 only allow fluid to flow into the chamber through and 0:18:43.440 --> 0:18:46.240 that's that's coming in from the low pressure side of 0:18:46.280 --> 0:18:50.840 this air conditioner system, so it's pulling the the refrigerant 0:18:50.920 --> 0:18:54.600 gas into the chamber. On the other side, you have 0:18:54.840 --> 0:18:58.960 the outtake or the the discharge valve. Is trying to 0:18:59.000 --> 0:19:00.600 think of the right word for it, This charge valve 0:19:00.600 --> 0:19:02.880 would be the right word. So now this valve only 0:19:02.920 --> 0:19:05.959 allows fluid to pass out of the chamber. This pushes 0:19:05.960 --> 0:19:09.520 it into the high pressure side of the air conditioning system. 0:19:09.560 --> 0:19:11.800 So you're pulling from the low pressure pushing into the 0:19:11.840 --> 0:19:16.920 high pressure. And both of these valves are essentially spring loaded, okay, 0:19:17.040 --> 0:19:19.200 so there's a certain amount of pressure, that's a certain 0:19:19.240 --> 0:19:22.679 amount of force that's created by the spring that the 0:19:22.800 --> 0:19:24.879 system has to overcome in order for the valves to 0:19:24.960 --> 0:19:29.359 open in either case. So you've got the piston down 0:19:29.359 --> 0:19:32.560 at the bottom of this chamber, so it's down against 0:19:32.560 --> 0:19:36.600 where the valves are. The piston starts to pull up, 0:19:37.160 --> 0:19:39.640 all right. This this creates an area of low pressure, 0:19:40.080 --> 0:19:43.359 which creates suction. Now, once that force of suction is 0:19:43.400 --> 0:19:48.440 strong enough to overcome the spring force of the intake valve, 0:19:48.720 --> 0:19:52.560 that valve will open. All right. So you're you're you're 0:19:52.600 --> 0:19:55.480 pulling hard enough to overcome the force of that spring. 0:19:55.920 --> 0:19:59.760 The valve opens, and that pulls the free on gas 0:19:59.800 --> 0:20:03.520 in to that chamber. All right. Once the piston gets 0:20:03.560 --> 0:20:06.920 to the top, it stops for a moment that allows 0:20:07.000 --> 0:20:10.240 the spring to close on the intake valve. It is 0:20:10.280 --> 0:20:13.280 now there's no more fluid coming into the chamber, and 0:20:13.320 --> 0:20:16.080 the valve itself is closed. The piston then starts to 0:20:16.920 --> 0:20:20.920 move down. This starts to compress the gas inside the 0:20:21.000 --> 0:20:23.919 chamber eventually create you know, it starts to increase the pressure. 0:20:24.040 --> 0:20:26.199 Eventually that pressure is going to be strong enough to 0:20:26.400 --> 0:20:30.359 open up the discharge valve. The discharge valve opens, and 0:20:30.400 --> 0:20:32.200 that means that the free on gets pushed into the 0:20:32.280 --> 0:20:34.800 high pressure system. You might ask, well, why is that 0:20:35.000 --> 0:20:37.520 high pressure on that system. It's because at the end 0:20:37.560 --> 0:20:42.360 of that side of the air condissuer system is that uh, 0:20:42.440 --> 0:20:46.960 that expansion valve alright, the expansion valve is sort of 0:20:47.000 --> 0:20:50.359 a bottleneck point. And because you keep pressing more and 0:20:50.400 --> 0:20:53.960 more gas into that side and the expansion valve only 0:20:54.000 --> 0:20:56.000 allows a little bit of that gas to escape at 0:20:56.000 --> 0:20:59.760 a time, the pressure increases, right all right. Actually, and 0:21:00.119 --> 0:21:02.439 at that point it's not really gas, it's liquid. But 0:21:02.440 --> 0:21:04.760 we'll get there. So you've got the piston moving, and 0:21:04.800 --> 0:21:07.159 it's moving at an incredible speed. We're talking like a 0:21:07.240 --> 0:21:11.239 thousand rpm, so a thousand repetitions per minute. So when 0:21:11.280 --> 0:21:14.600 I'm talking about this process of the piston coming up, pausing, 0:21:14.640 --> 0:21:17.560 and coming back down, it's doing that multiple times a second, 0:21:17.680 --> 0:21:22.320 something like between seventeen and twenty times a second. Uh. So, 0:21:22.520 --> 0:21:26.280 you're pulling that free on or other refrigerant through the 0:21:26.320 --> 0:21:30.400 low pressure system into that chamber into the high pressure system. 0:21:30.480 --> 0:21:34.000 The this this gas, once it gets pressurized this way, 0:21:34.080 --> 0:21:37.960 it starts to the temperature starts to climb. So now 0:21:38.000 --> 0:21:40.919 the temperature of the freon has increased, that's when it 0:21:40.960 --> 0:21:45.200 starts to move through the condenser coils, and that's when 0:21:45.200 --> 0:21:49.639 it starts to release heat to the environment. Now it 0:21:49.680 --> 0:21:52.119 may release the heat directly to the environment. This is 0:21:52.119 --> 0:21:53.440 why if you were ever to look at an air 0:21:53.440 --> 0:21:57.080 conditioner outside and you see this this series of little 0:21:57.160 --> 0:22:00.600 tubes that are kind of criss crossing, a wiggling back 0:22:00.640 --> 0:22:03.480 and forth across a large surface area. Those are the 0:22:03.520 --> 0:22:06.440 condenser coils. I think of them as metal intestines. There 0:22:06.440 --> 0:22:10.160 you go, do not touch those. They are hot. And 0:22:10.480 --> 0:22:13.040 the reason they are hot just because they're releasing heat 0:22:13.160 --> 0:22:16.040 into that into the atmosphere. If this didn't work, then 0:22:16.160 --> 0:22:20.200 air conditioners wouldn't work. So the heat starts to pull 0:22:20.240 --> 0:22:23.720