Hey thanks for watching this video. This is a much requested topic and it is a little bit of a maybe a dry topic. It's not the most technical, but it's a really good place to start for those of you who want to get into the HVAC industry, because in order to pass the EPA 608 exam, which is the federal exam that everyone who works in our industry has to pass. You have to become EPA certified to work with refrigerants.

That's what that certification allows you to do legally, and this exam does cover some things that are sort of ubiquitous. You got to know it in order to do what we do now. First thing to know about the 608 exam: just because you pass it, that does not mean that you are capable of working on equipment and it doesn't even mean that you're legally allowed to work on equipment in most states. You have to either work for a licensed contractor, or you have to have some sort of additional certification, but the EPA 6:08 is the only National exam that relates specifically to the handling of refrigerants.

There are some other types of exams: there's the EPA motor vehicle exam called the 609, but for what we talked about in our industry, that's sort of typical unitary duct lists window units, all the type of equipment we work on the 608 exam is the one that Applies and to start with, there's four different sections to that exam. There's core and you have to pass core if you're going to move on to any of the others. So you can't get any of the other certifications unless you pass core there's type 1, which is small appliances containing under 5 pounds. There's type 2, which covers most of the equipment that we work on and sort of the residential in commercial industry would be high pressure and medium pressure appliances and then there's type 3, which is low pressure appliances, which are generally going to be large centrifugal chillers.

That's the most common application for those, so for most of us type 2 is the most important. I would suggest that you will at least get type 1 and type 2 for most of the industry, and it doesn't hurt to get Universal and Universal is. When you have the core type, 1 type, 2 and type 3, you would be considered to be 608 universal. Certified now, once you get your certification once it's good for your entire life.

Basically, what you're saying is that you know what the regulations are and you're going to continue to keep up with them, because they do change. The regulations can't change and we saw some new rulings come down in 2018. That have then been changing a little bit sense, but just because you take it once that doesn't mean that you're not obligated to keep up with the new rule changes as they do change. It's always possible that the rules could change and they could make you recertify.

But to date they have not made us recertify, since the epa 6:08 came out in 1994, so 1994 is when you had to start taking this exam, and since that time there has not been any recertification requirements. It's once for all in order to be able to handle and purchase refrigerant, you should not be able to go down to a local supply house and purchase refrigerants unless you have an EPA 608 certification again depending on the type of refrigerant it is. There were some new rulings that included HFCS and that and now that since been changed, there's a lot of these rules that are in flux, I'm not gon na focus so much on the rulings that are in flux right now that are changing. We're gon na focus.

More on the things that are not changing and help prepare you to pass the 608 now we're starting with part 1 of core here, which is basically just an introduction to the 608 and some of the main things that you need to know. In order to pass 608, but one of the first things you need to know is where you can find more comprehensive resources. This is just a youtube video, some of the most comprehensive resources you will find are from ESCO, so you can find the ESCO website online. A lot of the local supply houses who give the EPA exam or schools are going to be using the ESCO test and the ESCO prep material, which are some of the best out there and then also mainstream engineering or quick products.

That's another site that you can go to that's EPA test comm and you can find a proctor and take the exam through that site, as well as get some great prep materials. So those are the two that I would recommend there may be some others out there. Rses also is a good source, so that's our SES org as well, but let's get started with some basics. The main thing that you're going to be able to do when you get an EPA license, is you, or at least federally allowed to handle and purchase refrigerants and systems containing refrigerants.

So what is a refrigerant? A refrigerant is a substance or a compound that is designed to change state and carry heat around. I mean that's the easiest way to think about it. It changes from liquid to vapor vapor to liquid and it moves heat from one place to another. We've talked about it before you need to know the basic four components of the refrigerant cycle.

That is the compressor which we call the pressure increase or the condenser, which we call the heat rejector. The metering device, which I call the pressure, drop or pressure decrease er and the evaporator, which we call the heat absorber and, just very simply, you have a line that goes in between the compressor and the condenser. That is the discharge line and that is filled with hot gas inside the condenser. It changes state from a fully vapor to a full liquid before it heads to the metering device once it gets to the metering device.

The pressure is decreased so that the refrigerant and then begins to boil and the evaporator boil or evaporate. So now it's changing state from liquid to vapor and then the line in between the evaporator and the compressor is fully vapor again. So both lines going in and out of the compressor are fully vapor. It's a hot gas discharge line going out of the compressor.

It's a cool suction line, going into the compressor. That's the basic return cycle just because you know that doesn't mean that you're capable of working on an air conditioner, but it is one of the first places that we like to start. So I suggest, if you don't know the refrigerant cycle and the common lines, specifically the liquid line, the suction line and the discharge line and where they connect start there and memorize that just memorize. It know the different states of the refrigerant in each of the lines and what each of the four main components do if you're new to the industry, if you're in school, you're studying for your EPA exam - and you don't have that down pat start with that, the Next thing that you want to do is you want to understand pressure and temperature relationships, so you need to be able to read a pressure temperature chart and it's very simple to plot, but when you see a PT chart you're going to have a refrigerant, so you Need to be able to locate the refrigerant you'll, see a pressure and the temperatures have a relationship and the only time that those pressures and temperatures correlate is when there is liquid and vapor present.

At the same time, that's what we call saturated. So the refrigerant is saturated, liquid and vapor is present at the same time. So we'll start with something very simple: like r22, a really common refrigerant that was used for many years at 40. Degrees r22 has a pressure of sixty eight point.

Five and all that means is that when r22 is at sixty eight point five psi and there is liquid and vapor present at the same place. At the same time, it will be 40 degrees or you could say the opposite if it is 40 degrees in liquid and vapor are present at the same place. At the same time, what we call saturated that it will be at sixty eight point, five psi and the times that we see refrigerant in its saturated form, are in the evaporator in the condenser and the evaporator. That's where it is changing state from liquid to vapor and in condenser.

That's where it's changing state from vapor to liquid, and so those will be saturated at those various points. So those are terms that you want to know. You want to know what a PT chart is that stands for a pressure temperature chart. You need to know how to read it, find your refrigerant, find the pressures and temperatures and go across and be able to plot that, and you need to know the term saturated and you need to know your basic components.

That is a place that I would start for almost everyone to help you get started. If you don't have a PT chart, you can look one up easily online or you can use the refrigerant slider app from Danfoss and it does the same thing. It just allows you to do it on an app either Android or iPhone, and we use that a lot at my company. A couple other terms that you need to know are: CF c, HC, f, c, hf c hf, o n HC.

So you need to know what those mean and again we're gon na move, a lot of words around, but one of the first things that you have to identify is this molecule called chlorine chlorine. You know we know it in our swimming pools, but it's especially harmful when it makes its way into the stratospheric ozone. Now quick disclaimer. Whenever I talk about these things, people will want to argue with me about politics and about the ozone layer and all this stuff.

I'm just telling you what the EPA has in its literature in order to get you to prepare for this exam. We're not arguing politics here. So please don't give me those comments, I'm just here to help you prepare for the EPA exam, so chlorine when it makes it into the stratospheric ozone, can break down ozone or o3 molecules, which then exposes the earth to more ultraviolet radiation. So ultraviolet radiation is caused by chlorine, making it into the stratospheric ozone and breaking down.

Oh three molecules: we've been discussing this problem all the way since the 80s, and what we found out is that refrigerants have something called an O DP or ozone depletion potential. So you're gon na see that a lot ODP means ozone depletion, potential and refrigerants that carry chlorine have an O, DP or ozone depletion potential for refrigerants that do not have chlorine. They do not have an ozone depletion potential, but that doesn't mean that they don't have a GW P or a global warming potential which is due to greenhouse gas. So those are different things.

But when we talk about CFCs and HCFCs, those both have chlorine, because CFC stands for chlorine, fluorine and carbon chlorine. Fluorine and carbon HCFC stands for hydrogen chlorine. Fluorine carbon CFCs, common ones back in the day where r12 used to be used in cars and a lot of different systems and our 11 used to be used in chillers. Those were both CFCs and those were completely banned.

A long time ago there was a phase-out if you remember, when cars went from r12 to 134a. That was many years ago nowadays. What we saw most recently was a transition away from HCFCs, hydrogen fluorine chlorine, carbon to HFCS, hydrogen fluorine carbon. So, if you think of it, this way getting rid of the chlorine, gets rid of the ozone depletion potential.

That's when the chlorine molecules make it up to the stratospheric ozone breakdown, the ozone layer by breaking down the o3 and exposing the earth to additional ultraviolet rays. These are the sorts of questions that will come up on the test nowadays, two of the other types of refrigerants that we're talking about a lot are hf, o s or hydro, fluorine olefins. I think I said that right, a hydro, fluorine, olefins and then H, C's, which are hydrocarbons and so HF OS are the newer ones that you see in cars like 1, 2, 3, 4 YF would be a common one that we see now in cars and then Hydrocarbons are flammable refrigerants, and many of them are natural, so propane would be a hydrocarbon or isobutane would be a hydrocarbon advantages of hydrocarbons. Is that they'd have a zero ozone depletion potential because they don't contain chlorine and they have a very low global warming potential, but they are flammable.

So that is a challenge that they face. So you will want to know some of the common refrigerants. So we'll talk about this a little bit more in the next episode of this. You want to know some of the common refrigerants that we've seen in our industry for a long time, r11 and r12 being some of the earliest, at least in this sort of second generation of refrigerants.

We had a first generation a long time ago. A lot of them were poisonous and toxic, and so we went to the second generation in which our 11 and our 12 were popular, but those are ozone depleting because they contain chlorine. Those are CFCs. Then we went into sort of the r22 era.

R22 was popular for a long time. It's the refrigerant. A lot of people called freon when people would say. Do you put freon in your home air conditioner? That was our 22 or even our 12.

They would call freon that was an H CFC, so it had hydrogen fluorine chlorine. Carbon still had chlorine, but it wasn't as ozone depleting. That was an H, CFC and now commonly today you will see. Hf sees those be things like r410a r134a.

Those are HFCS. Those are also beginning to be phased out because many of them have high global warming potential numbers, and nowadays we have things like 1, 2, 3, 4 YF in cars, which is an H, fo and then more Naturals, such as hydrocarbons, that we see like propane and Isobutane and then Naturals like co2, even being used as a refrigerant, so more and more different types of refrigerants coming out because of concerns with the environment. A couple other terms that I want you to know three terms that are commonly used throughout the 608 exam are recover, recycle and reclaim. So what we do in the field when we take some refrigerant, we put in a tank typical sort of technician stuff.

We are recovering refrigerant, we're removing refrigerant from the system. We are not allowed to vent that refrigerant. That's again, that's a very basic EPA, 6:08 stuff for anything for all of the regulated refrigerants, which would be your HFCS or CFCs. Your HCFCs or HF OS you're not allowed to vent those refrigerants.

The only ones that you are a lot of n time generally are going to be Naturals like co2, like propane. Those are the only ones that you can release into the atmosphere, so we have to capture those in the field, and that is what we call recovery. So when you take refrigerant out of the system - and you put it into a tank that is called recovery, if we use a machine to do that, we call that active recovery because you're using the compressor from a separate machine. Those recovery machines now have to be EPA certified and we'll go over some of the additional rules and some of the next segments of this series, the modern day all the equipment you're going to see.

Nowadays, those recovery machines are there to pool refrigerant out of the system and to put it in a tank. When you fill a tank, you are not to fill a tank with more than 80 percent liquid. So that's just an overall rule we'll go in some future episodes about how to know exactly when you reach 80 %, but you need to make sure that you do not fill them more than 80 % and that will on the core part of the exam. So watch out for that, the next thing that will sometimes be referenced is recycling.

Now recycling you will sometimes see in the automotive industry, and that is where, when they pull it out, they actually clean it. By running. It's usually several passes through a line, filter, dryer, and then they will return it. So recycling is the process of intentionally cleaning the refrigerant in the field or helping to remove some of the contaminants in the regular HVAC industry.

We don't do that very often, but that's what recycling is and then reclaiming refrigerant is when it is sent back, and it is processed fully at a at a facility and made pure enough that it can be brought back and resold into the field when you recover Refrigerant in the field, so it's let's say I as a technician, take some refrigerant put it in a tank. I can't now take that refrigerant and sell it to somebody else. In fact, I can't even give it to anybody else who is not the same owner in the same facility, so I could take it within a facility say it was an apartment complex and it was the same owner. I could potentially use that refrigerant within that owners.

Same facility, but I couldn't take it and sell it to somebody else, even at a discount or even for free, because that comes up quite a bit. That's not legal, but you can send it back to a facility to be purified in the reclaiming process. And then it can be returned now, a lot of times. People will use those three terms recover, recycle and reclaim as if they're the same, and they are not and that's important to know when you're taking your 608 exam.

The final thing I want to talk about is flammability and the toxicity of refrigerants. This is a pretty easy one to understand a refrigerants refrigerants that, where the letter starts with an A is a refrigerant that is non-toxic. If it starts with a B, then it is toxic. The vast majority of refrigerants that we work on are non-toxic.

Ammonia would be an example of a refrigerant that's used in process, refrigeration or in ice rinks, and that is a B refrigerant being a toxic refrigerant. Then we have a 1 which is non-toxic non-flammable or B 1, which would be toxic non flammable, so a 1 is non, flammable 2 would be somewhat flammable there kind of in between, and then 3 would be. Very flammable so propane, for example, would be a three refrigerant because it's very flammable. So again we have very few B refrigerants that you're, typically going to work on you will see.

Some are 123 are, 717, are 30, have some toxicity to them, but in the a category you have a ones which have no flame propagation, a 2l which has slightly more than a one. So it does have some flammability, but it's not as much as in a 2 and then a 3 which would have very high flammability, like our 290, also known as propane. So if you think a one being least flammable a three being most so goes a 1 a 2 L, a 2 a 3 all right. So that's it start with understanding the basics of the refrigerant circuit.

Understand the difference between recovery, recycling and reclaiming understand some of the basic refrigerant terms: CFC HCFC, HFC, h, fo, +, HC refrigerants and then understand the number letter. Flammability toxicity chart just a little bit. That's a good start if you're studying for the exam make sure that you're reading the booklets from again, whoever you know your instructor or whatever, but also you can find them by getting the booklet from s co or mainstream epi test comm is a really good source. I take some practice exams.

That's another really good thing to do before you get ready to take the EPA exam so we'll catch you on the next one. In the meantime, keep studying.