Hey thanks for watching this video is another in our series of epa prep videos, and to be clear when i do these. This is just a quick introduction. This is not going to cover everything, but it gives you some of the common things that come up on the epa exam as well as just some general good information that may not be on the exam, but are good things for you to know. If you want to be fully prepared for the epa exam, then i suggest that you go to esco or to mainstream engineering.

Epatest.Com is the mainstream engineering site and escogroup.org. Those organizations will help you get certified. Also rses is another good organization that will help you get prepared for your epa exam. But this is, you know a little extra just to help you get prepared, we're talking specifically about type 1 certification type.

1 certification is relating to certification to be able to handle refrigerants charge, recover anything associated with the refrigerants in the refrigerant cycle of systems that contain less than five pounds and are manufactured charged and hermetically sealed in a factory. So some common examples of this would be refrigerators and freezers, small ones or small package units or window units. Those would all be some some common applications. Also, maybe vending machines would fall under this category systems that are factory charged and sealed and they contain less than five pounds of refrigerant.

So the first thing um there's this there's this kind of caveat within the epa regulations, because a lot of this changed on november 15. 1993. That's a a date for you to remember! If you're working with recovery equipment so equipment, that's designed to pull the refrigerant out of the system that was built before november 15, 1993, then you're only required to remove 80 or the equipment is needs to be capable of removing 80 of the system refrigerant. Now that may show up on the exam.

So it's something that's important for you to know. From a practical standpoint, i doubt any of you are using recovery equipment that was manufactured before that date, which means that the system needs to be capable of removing 90 of the refrigerant. From a even more practical standpoint, when you are connecting a recovery machine to a piece of equipment that is a kind of a typical high pressure, medium pressure type of refrigerant, then you really want to pull it to at least atmospheric pressure valve it off and make Sure that it doesn't rise above atmospheric pressure before you open it up for servicing, just a practical standard um that most of us follow in the field. Another thing to know from a date, standpoint november 5th 1993 equipment that was manufactured after that date is required to have a processed up process.

Stub or processed stubs are little stubs that you can then use to access the system with say a piercing tool or with a crimping, a crimp off tool that you then cut the top off and you put a schrader stub in place. I never recommend that you leave a piercing type valve in place, regardless of the type of refrigerant you have in the system, because those piercing type valves do tend to leak, but you can use a piercing type valve in order to get access to the system refrigerant. So that it can be recovered again, you can also use in many cases those process stubs. You can pinch them off, you can put a port in and then you can kind of round them back out in order to recover the charge.

Another really big distinction that i always want to make is that there are cases and not all cases, but in some cases you can retrofit one refrigerant to another refrigerant. You can change from one refrigerant to another refrigerant. This does not mean you are allowed to top off one refrigerant with a different type. So let's say you have a system.

That's got some 134a in it. You can't go in with some new modern, uh hydrocarbon or one two, three four or something like that. You can't go in on top of that existing charge. You have to remove all of the existing refrigerant and then recharge with the new refrigerant in small appliances.

You're generally going to be weighing in that charge, so you can't top off, and systems are not drop-ins in the sense that you can't take a refrigerant and drop it in on another, and you can't field mick, for example. R410A is a common refrigerant. That's a mixture of two refrigerants, but you can't take r32 and r125 and field mix them in order to create r410a. That's not allowable.

It has to be certified in this jug as the refrigerant that it's designed to be that end refrigerant. Another thing to keep in mind is sometimes you'll run into old refrigerators, things that have been in service for a really long time and they may contain refrigerants, such as ammonia, sulfur dioxide, methyl chloride, methyl formate when you run into these types of old refrigerants sort of This first generation of refrigerants that are can be toxic and corrosive. You do not want to use typical recovery equipment with those refrigerants, so in those cases you want to stop, you want to have a conversation with somebody who has some experience with these refrigerants, rather than just proceeding and recovering them. Like usual, another thing to watch out for is a lot of new small self-contained equipment contained hydrocarbon, refrigerants hydrocarbon refrigerants are refrigerants, such as propane or isobutane, r290.

Being probably the most common. Many vending machines and small refrigerators, especially for the commercial sector, are coming pre-charged. You have to be extra careful because you can't just use a torch on a system like that without making sure that it is fully removed. Now, as it relates to this, this is not a course on hydrocarbons.

Just know that you need to take extra care. If you have hydrocarbon refrigerants in place and also you don't field mix hydrocarbons like any other refrigerant, hydrocarbons can be vented in many cases, because they're natural, and so that is allowable in many cases. But even then you want to make sure that it's vented in a safe area and it's a good practice to chase it with some nitrogen once you're done, venting it to ensure that you don't have any residual, also just be really cognizant of where you're venting to So that way, you don't potentially create a flame or have those fumes associated with those hydrocarbon refrigerants. Another thing: when you open a system and you find that it has zero psi, you put a saddle valve on it and you find that it has zero psi.

Don't hook a piece of recovery equipment to it because you're likely going to pull air in from the outside. So if you connect to one of these small appliances and you're at zero psi, that's all you need to do. You don't need to worry about any of those residual vapors that are inside there, potentially, because in putting a recovery machine on that you're going to be likely to pull more atmosphere into that system and make the situation worse whenever you're working with nitrogen. This comes up a lot in type 1.

Prep just know that whenever you're using nitrogen, you always need to use a nitrogen regulator specifically designed for nitrogen. So it drops that pressure down nitrogen comes under very high pressure. You would never want to use full tank pressure when working with nitrogen also keep in mind when working with refrigerants that contain chlorine, cfcs and hcfcs. That would be like your old r12s r22s r11s.

When they have chlorine, when they're exposed to a flame, they can create something called phosgene gas and phosgene gas is toxic. It's really nasty you'll know it when you smell it, but when you're working in with those types of refrigerants, you have to make sure that you've recovered as much refrigerant as you can and then also purge some nitrogen through to ensure that you're not going to have Phosgene gas, also just as a general practice when i'm talking about things like purging nitrogen, you never want to work on a system with a flame that is under pressure. You can be flowing nitrogen, which is the best practice to make sure that you don't build up carbon inside the system, but you never work on a pressurized system. You never you apply a torch to a pressurized system.

Again, there's a lot in this test about different types of recovery machines and that's sort of standard that november 15th. 1993. There is a lot of changes that occurred there and then there's a lot of there's a lot of talk about self-contained recovery devices which are the ones that we're used to they're, designed to pull refrigerant out of the system or system-dependent recovery devices. And that means that they rely on primarily the compressor in order to get the refrigerant out of the system.

And we all know that you can hook up to the high side of a system and allow it to run. As long as you have an operating compressor - and you can get some of that refrigerant out in modern terms when we're talking about recovery equipment, we're pretty much always talking about self-contained recovery equipment. Finally, practice really good safety whenever you're working on a small appliance like any appliance, make sure that you're wearing safety gear gloves goggles and also keep in mind that refrigerants are heavier than air and they do settle, which means that they can displace oxygen. And it can be dangerous now again with smaller appliances, it's going to be less likely that you're going to experience this because they contain less refrigerant.

But if you're in a very small contained space, then you are at risk. If there is a venting situation where refrigerant has has vented another thing to mention quickly, the term de minimis comes up a lot. We're going to talk about this in some of the other segments as well. The minimus just means that some losses that occur while a technician has is making a good faith effort to connect and disconnect from the system for the purpose of recovery and charging or unintentional venting.

That occurs because things happen, compressor blows. The terminal the system leaks, the epa does not restrict those sorts of leakages as long as it's not an intentional venting event where you are not taking proper practices, and now you vented, because you've done something literally wrong or intentionally vented in most cases, for a technician Doing their job hooking up gauges, you know you have that little bit of refrigerant that's lost or a little bit in a hose. That's all considered to be de minimis. Now they do have a standard.

The epa does have the standard about low loss fittings being attached to recovery equipment. So, specifically, the recovery equipment does need to have low loss fittings in place, but that's not necessarily true for things like you know your probes that you're connecting and disconnecting from the system as a just best practice whenever you're working with systems that have smaller charges. You really don't want to use uh gauges that have hoses manifolds that could potentially hold a lot of refrigerant in the hoses use, probes and small t's or very small six-inch hoses in order to access the system. So that way it reduces your loss all right.

So that's it for type one. We cover a lot more in the core seg section of this series, which is part one and part two core part, one core part: two, the next video is going to be on type 2, which is actually probably the most common type of equipment that we work On in the field and residential and commercial, and so we're going to cover a little bit more there, but it's going to be good for you to watch these in sequence, start with core and work our way through, because we cover a lot of things. That would be in these other segments, in course, so terms like hcfc, hfc, cfc and a lot of those other sorts of you know acronyms and dates that may be important on the exam again just as a reminder, this video is only to be used as a Supplement just to maybe help you remember some things uh at the last minute you know or just a quick refresher. This is not a replacement for a complete epa study guide, which you can find from organizations like esko, rses or mainstream engineering.

Hope you found that helpful. We'll catch you in the next video you.