This episode of the HVAC school podcast is made possible by our sponsors, the carrier, corporation, testo and rector seal. I want to remind you that my favorite set of digital gauges - and this has been true for many years - is the testo 550, just what you get for. What you pay and the quality of the product is really unmatched and that's been true for many years, and I'm gon na highly suggest that you look at the testo 550, if you're in the market, for a digital manifold and the best way to do. That is to go to true tech tools, com and, if you're interested in purchasing it use the offer code or coupon code.

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My shelf products like true blue thread, sealant, which truly is a better thread sealant than a lot of the other brands that you're going to see out there there's some there's some brands that are also blue thread sealants, and I prefer true blue to those products. It more than anything else, I want to thank carrier, testo and rector seal for partnering, with this new wave of making technician, training free to every technician and apprentice out there. Who's interested in pursuing the trade like I've said many times before. What we produce is for professionals or those who are interested in getting into the trade.

It's not low enough fruit that a homeowner could use this information. We are doing this for those in the trade to help fill the skills gap and take those who are new in the trade or maybe even those who are experienced and have forgotten some things get them the skills, get them the knowledge that are really gon na Help them this is not a replacement for doing the hands-on work, but companies like testo carrier and rector Co who get the direction that the industry is going and if partnered with us, they get it, and I really appreciate it. Okay, thank you for listening to the hvac school podcast. I am brian, and today's episode is about brazing and hvac are pipe fitting.

When i can talk about soldering today, there is a case being made for some products for soldering and hvac are, but today we're not talking about that, and although some of this will apply, we are talking specifically about brazing, but before we do anything else before we Go any further with brazing, I do need to talk about safety and there are some. You know. I don't talk a lot about safety here. Cuz, there's a lot of training out there.

That's that does a better job. I tend to focus more on the technical, but in in this subject, brazing safety is totally central to the to the whole endeavor, and so the first thing is: whenever you're gon na be working with equipment that creates fire. You want to make sure that you know your. You know your gear, and so, if you, if you get a new set of gear, you want to make sure that you read all the all the instructions and you understand it really.

Well, I'm not going to talk about the very basics of how to use a regulator, for example, so you want to know those things and you want to make sure that your hoses are in really good condition. You know have any cracks or anything that's been crushed or damaged on your hoses are under regulator, so you don't want to have a regulator that the dial is falling off. You know I see this all the time, so the first step is just to make sure that your gear is in really good condition and that you understand it, you you understand how it works, and you know exactly what you're doing. That's the first thing.

So don't pick up a box acetylene torch kit, which is by the way. What we're talking about here primarily is ox acetylene. There are other setups, but that's primarily. What I'm going to be talking about here is the most common which is ox acetylene.

So you need to make sure that you know what you're doing before you get started with this. The next thing is make sure that you have safety glasses on when you're, braising or soldering, so have your safety glasses in place that cover not just in front of your eyes but around the edges generally is a good idea as well for most most basic brazing And HVAC are and then also make sure that you're running gloves, protect your hands, protect your arms just make sure that everything is well covered whenever you're going to be brazing, it's a good idea to have some damp rags near you in case. Something were to ever get out of hand and say you burn yourself, for some reason have some have some rags there or if you need to handle something quickly, you having some rags is always a good idea, damp, rags and and also as we're gon na talk About later, you want to be able to make sure that you're not gon na damage whatever it is, that you're braising near so just having some damper act, handy and maybe even a little bit of water is a good idea and then, in addition to that, you Want to have a fire extinguisher handy so anytime, really no matter what you're working on there's always the possibility something could catch on fire, especially when you're inside a space you want to have a fire extinguisher handy. Obviously, I'm not talking about cases where a fire spotter is necessary, that's a whole nother whole another deal and in some cases that may be the case, so you do need to think about the application.

You know: where are you working? What are the conditions around you and make sure that you're that you're, following all the best practices related to the situation, that you're bracing and but in general, if you're, working at a typical residential environment or like commercial environment, you really just need to make sure that You have a fire extinguisher, you have in your proper safety gear. You understand, you were you're brazing rig and make sure that it's in great condition before we get started and have some wet rags, and maybe some water handy as well. You also want to make sure that you have if you're gon na use, you know channel locks or something to handle some fittings. You want to make sure that all of that's ready anything you're gon na need to hand to do the handling you have that all ready and in place one other consideration is just make sure that if there is a fire system or smoke detection systems or those Sorts of things that you've taken into account where they are and what your you know, how you're going to deal with the with the situation.

If you have a you know fire sprinkler system. Obviously you have to be super careful. You have to make sure that you're not going to trigger a fire sprinkler system or an ansel system, or something like that. I, when you're working in commercial environments, so it will be very, very careful.

And if you have those sorts of considerations, you want to be very diligent to talk to the customer and make sure that you take all of the proper precautions which I'm not going to go through. What all of those are right here. But you need to make sure that you're paying attention even a residence just regular smoke, alarms, you're gon na want to make sure that you have those address so either covered, or maybe the one closest to where you're going to be working removed temporarily and have a Conversation with the customer, letting them know that there's always the possibility that it may go off and in those cases you want to make sure that you, you are well protecting the space. So if your gon na be working over carpet or something it's a good idea to put down some, you know metal, sheeting or the panel of the unit or something anywhere that there could be any possible solder, drips or anything like that.

You just have to really really think about the space that you're gon na, be working in and and be extra careful to make sure that you're protecting protecting that space. Another thing that I think I need to state that is not directly related to brazing, but it is the idea of uh none sweating, something so of heating up a fitting and pulling it apart in general. That's just a really bad idea. You only should you should only unswept something if it's an absolute must, because, anytime, you unswept a fitting and there's always the possibility that pressure is building up.

Even if you have the, if you have the system open and so the way it can escape. There's always some pressure build-up at the act, the actual point of heating and then also the oil will often catch fire. The refrigerant will catch fire when you when you pull it apart, so I generally recommend not unswept and then also whenever you on sweat. Let's say you're on sweating near a dryer or something of that nature.

You can often release moisture into the system by doing that, so in general, it's better to cut things out of the system than it is to unswept. If you do need to unset, just make sure to take extra careful precautions that when it comes apart, if oil does catch on fire, it's not going to damage something grip on something damaged, wires burn you! You know all those sorts of things just make sure that you're in a really good position, well-ventilated also, obviously phosgene gas - is a major consideration. The burning of refrigerant that lets off poisonous phosgene gas and so unswayed is always something to be really really careful of forests. But even even when you're braising, something in you can have these types of conditions that can occur.

So you always want to make sure that the system is open to atmosphere, so that pressure can be relieved to atmosphere which goes into what we're going to talk about and a little bit about the flowing of nitrogen while braising. So once you know your gear and you have everything set up and your and you've got your safety gear on, and you know the space that you're in and you make sure that you've taken all the proper precautions now it's time to actually think about what are Some of the best braising practices the actual doing of the work, so the first thing is in to me. This is probably one of the most important factors is that whenever you're working with copper lines, you know refrigerant lines. You want to make sure that you're keeping stuff out of them, and so some of these practices that we're going to talk about or whether it's you know using flux which today we're not going to talk a lot about that.

But if you were to use flux or if you're, reaming out copper, you know deburring the copper. These are all opportunities for stuff to fall in the pipe. So, whenever you're doing with copper, you need to make sure that you're not letting stuff and get into the tubing. So this is an example.

You know an example would be if you're, if you're, using sand, cloth or Emery cloth to clean the copper, that's a important practice, something that you should be doing. But when you do that, are you letting those little pieces of the copper fall into the tubing? Are you letting that dust get into the tubing, so you have to be really thoughtful about that and when you're reaming and deburring copper, you want to make sure that you're holding it upside down to ensure that those little pieces of copper aren't falling into the pipe Which is something that I want to address. You know I'm a big fan of reading and deburring, so using an actual reaming tool. Reaming up the inside of all of your copper tubing left, you cut it that helps make sure that you're running the full diameter and it also leaves a smooth edge so that that way, you're not creating turbulence in the lines or, if you're, creating flare fittings.

For example, it helps you make a proper flare, so that's an important thing to do, but if, in doing so you drop some copper shavings in the tubing, it would have been better that you didn't do it in the first place and the same thing is true Of cleaning the copper with Emery cloth or sand cloth, it's important to do, but if, in the process of doing it, you're being sloppy and not careful and you're, contaminating the copper you're getting solid contaminants in the copper, it would have been better that you didn't do It in the first place, so whenever you're prepping your copper prepping fittings using flunks, reaming and deburring your copper, you want to make sure that you're being really careful to not get anything in it, and I see a lot of guys who will you know kind of Blow in it and or do those sorts of things well, I mean that that's not a technical way of doing that. Besides the fact that you know blowing in copper with your breath and spittle isn't the best practice, so it's better to make sure that you don't get it in there in the first place and one of the easiest ways to do that is when you're, when you're Reaming deburring cleaning to hold the copper with the open end pointed down so that nothing gets into it, but when it comes to preparing copper or and we're talking, copper to copper here, which is really what I'm gon na focus on we're gon na do a whole Separate this is a basics: podcast we're talking the basics of brazing, so we're thinking, copper to copper. Here you want to make sure that you prep the copper in such a way that it's clean and then it's very tight. So you we've probably all seen situations where a technician will take a suction line and insert it into a condenser and that condenser suction lines too large and so they'll take it and they'll just pinch it down and solder it you don't raise it.

You don't want to do that. You want it to be a nice tight fit and if you need to use bushings or reducers in order to get it a nice tight, fit all the way down, then then do that all right in some cases have I used different diameters of copper in order To create my own field reducers and maybe a swedge tool in order to make those reducers sure and that's okay. But you want to make sure that it's being reduced all the way down and that your reaming deburring and cleaning the copper at every stage. So that way, you've got nice tight, clean fits with everything, all the birds, so you don't have that little edge and the inside that creates turbulence and the refrigerant, because really what we want to have is we want to make sure that we have a really good Seal we've, you know we're really making sure that we're sealing it well when we braise, and that also the inside diameter of that copper isn't compromised.

And what can happen - and I saw this one time with a compressor. Somebody took a compressor and they installed a discharge line that was smaller and they attempt to just bridge that difference in size. So you had the the female fitting on the compressor and you had small diameter, a copper discharge line going in and they just attempt a bridge and what happened is that is the solder was pulled in to that. The the rod was pulled in to that fitting and it actually blocked the discharge line partially, which caused all sorts of weird hard to diagnose problems, because the compressor wasn't producing the capacity that it should.

It was overheating and so on and so forth. So you don't want to create bridges with solder or brazing rod. That's not that's not what you want to do. You want to make sure that you have nice tight, fit all the way around and keeping some various size of reducers and fittings and different sized tubing of copper and having a good quality swedge tool on your truck.

I recommend a lever or a hydraulics wedge. It's gon na be a really good step, a nice way to be able to create reducers when you need them as well as making sure that you have a good reaming tool. The reaming tool that i like is the one that you actually insert into the line and you kind of spin it around it's, not that it's not the triangle ones that you see on the typical tubing cutters, those I I don't have great luck with, but the Ones that have the handle, and then it's got like the little scythe looking. You know curved blade on it that you actually twist around in the in the pipe in the tubing.

I've had really good luck with those, so once you get all of your all of your tubing fit very tight and it's nice and clean it's been cleaned properly. What I generally do when I clean it, is I'll use a sand, cloth and Emery like a mesh Emery cloth clean it real, well and then use a and then use a dry microfiber rag to clean off any of the dust. That's gotten on it before I fit it together. That's a nice way of doing that, but once I get everything kind of all together now the next phase before I start to actually setup my my torch kit for brazing is going to be to start flowing nitrogen, but before I even flow nitrogen, I need to Purge with nitrogen, which is an important step that sometimes gets missed, because when you've had a system, that's open to atmosphere, you not only need to flow nitrogen through it, but you need to initially get all of the air all the atmosphere refrigerant out of it.

So that that way, it's only nitrogen going through so the best way to do that is to just hook up a nitrogen regulator. I like the western enterprises regulator. It actually has a separate test, which is high-pressure purge, which is like a medium pressure and then a it says: BRZ, which means braze, so that you can. You can just easily use that regulator and go between those three.

But the point is you really want to just make sure you've flown some nitrogen through it at a decent rate? You know pushing some nitrogen through that entire system and then making sure that you're kind of flushing everything out before you start flowing nitrogen at the very low pressure. When I say pushing everything out it's to get all the atmosphere, all the air out displace all the refrigerant, that's in the system as much as possible. So that way, you know you just have nitrogen in the system. Now some people have asked.

How do you know what is enough? Well, I mean there's not really a good typical way of doing that. You just you just do it, for you know three, four, five six seconds on an average situation if you've got a like a long commercial job where you've got long runs of line that you've done and you fit them all together and now you're going to be Flowing nitrogen well, then you're going to want to do it while so that way, you make sure that now what's flowing through those lines is nitrogen. You know you can overthink these things. It's it's a big of a deal.

You just want to make sure that you're displacing the air, moisture and refrigerant that's in that system and then replacing that with nitrogen once you're then ready to braise. That's when you put it on the flow setting and so on the western enterprises regulator. That's the BRZ! Setting, if you don't have a fancy regulator, then you have two options. You can use a secondary regulator, which you know well makes the secondary regulator there's a lot of different companies that make it, which is an actual flow regulator and a regulator like that.

A secondary regulator, it doesn't use psi, it uses CF, h or sometimes it'll, say s. Cf H, which stands for cubic feet per hour or standard cubic feet per hour, essentially means the same thing. So it's very very low flow rates. It's not a pressure reading.

It's a flow reading, and so it flows a very, very small amount, and if you don't have one of those fancy regulators don't worry, you can use your regular nitrogen regulator, but you just want it to put out so little that you barely even it barely even Shows that on the gauge, so what you do is you just you turn the dial out on your regulator and you start to turn it in because, as you turn it in that's what increases the pressure you turn it in until you can just barely feel or Hear a whisper of pressure coming out the other end, the outlet side. You always have to leave one and open on the far side when you're flowing nitrogen. So if you're putting it in one side, you have to leave it open so then flow out. The other side, and so, if you just place it up to your ear, you can just hear just a whisper coming out.

That's how much nitrogen you want to flow! You want it to be just enough so that it is moving through the lines, but not so much that it's going to blow out your joints now the challenge comes because, depending on where your ports are, you know it depends on what type of what type of Bracing job you're doing if it's a typical, you know just installing a line set on a new piece of equipment. That's a piece of cake! You just work around in a circle and you get back to the other port and you're done, and it works just fine. But if you're doing say something like a reversing valve or a compressor, it can get a little more tricky to figure out how to flow a nitrogen, because you don't have an easy way to do that in some cases, and so what you can do is you Can flow all the way till the very last joint and if you can't flow in the last joint just right up to the last second make put the joint together and then shut off your flow. There's not gon na be any air to speak of in the system and that's okay, if you shut it off on the very very last joint, it's not gon na hurt anything.

Someone wants to argue with me about it. Fine, but trust me. It's not gon na be a problem, so in some cases you know you can flow all the way to the last one, but in general, if you're doing a line set on a new system, you can flow all the way around. You just have to kind of think about where you're starting and where you're finishing, but it does always have to be open.

You always want to make sure that the circuit it can relieve pressure. You don't want it to be a closed system because then, as you start to heat it up it pressurizes. So you want to leave a port open somewhere and flow to that port. If at all possible, again depends on the system depends on the application, and you know it's gon na vary slightly, but in, but you want to start by purging it with nitrogen.

So that way, it's full of nitrogen and then flow all the way until you you just can't possibly flow anymore, but that flow is generally two to three SCH, which is just a whisper of a flow and having a actual flow gauge like a like a you Know weld or using the western enterprises regulated that has that built right in just makes it easier to set that, and if you look at a you know, weld regulator or a lot of the other regulators that have been used for years and welding and brazing. You usually they'll have a little floating ball and basically you just want to barely float that ball once you have actually purged nitrogen, so the whole system's full of nitrogen. All you need is just a tiny, tiny, tiny amount of flow. So if that's all, you need to remember 2 to 5 SC, F, H or if you don't have one just flow it so that you can barely barely hear it, and you can generally do this with most nitrogen regulators.

It just takes a very steady hand, and - and sometimes you just want to get the pressure too high, because then it's gon na be difficult to braze. It's your joints aren't gon na hold, so you want to, you know flow as little nitrogen, as you can displace the oxygen. I think you get the point at this point. So now comes the question of how you actually set up your torches, and this is an area that technicians do not put nearly enough thought into.

So it's important that you look at your torch manufacturer specifications are many of you gon na. Do that you're - probably not gon na listen to me, but I'm gon na strongly suggest that you understand your torch manufacturer specifications not just for the torch but for the different types of tips, because if you read the specs for the tips, they're gon na tell you A lot about what those tips are designed for and a lot of you are using the wrong tip for the job. Essentially, what you should be doing is, depending on the science job, you should be going for a larger tip for a larger job, smaller tip for smaller job. But many of you don't do that.

You actually just adjust your flame to a more aggressive flame. If you have larger copper and a less aggressive flame, if you have smaller copper, it's not the best way of doing that, because really you're not supposed to be setting the output pressures at the handle of your torch at also, if you're adjusting the knobs on your Torch actually at the handle, that's not the way that you should be setting the flame by and large, and I understand that it's not practical that we're always going to set it at the regulator. But in general you want to set it up at the regulator and that setting is going to be a minimum of three oxygen. Three psi oxygen: three psi acetylene up to seven psi: oxygen; 7, psi settlin, but the two numbers should always be the same for brazing.

So those of you who are taught like me, 711 - don't do that do the same number. Manufacturers of brazing equipment will essentially always tell you that you should use the same pressure for oxygen, the same pressure for a settlement and then, when you light it they're gon na recommend that you light by opening the acetylene a little bit lighting it and then opening Your oxygen yeah it does, it create a little bit of crates and bunnies sure, but it decreases the chances that you're gon na have some flash back into the actual torch itself. It's just a safer way of doing it. I know a lot of you aren't gon na listen to me about that, but that is the technically correct way is to light the acetylene first and then, when you shut it off, shut off the oxygen first and then shut off the acetylene again, I know some Of you won't do that because of the little carbon flurries that you get, but that is the safest way of turning them on and shutting them off.

So then, what you're? What you're doing essentially is. If you have a larger tip, then that's producing more heat and again you're setting this actually at your regulator, you're not sitting in at the actual at the knobs. I know so many guys who just turn those those t-handles in on their regulators to put out maximum pressure, and that's not the right way to do that. They should start off with them turned out not so they fall out but turned out until they're loose, and then they turn on the tank knobs and then they just regulate at the handles.

I'm telling you that's a bad practice, so set your regulators and then, when you're done every time, loosen them up a little bit and then shut off your tanks and that's gon na be the safest way to store it and it's gon na be the best way. All around for your the longevity of your torches and also to get the the proper heat. So what it comes down to is you're gon na need to have a couple different torch tips, so you're gon na want to be in the practice of switching torch tips. When you're going to large commercial versus small - and I obviously I know that when you're, you know braising in a liquid line versus a suction line, and is it practical that you're gon na switch tips in between those two? No so you're gon na want to use something that works for both, and I understand that.

But you want to kind of think about this. So that way, you're using appropriate heat, because appropriate heat control is a huge part of making sure that you're gon na get a good seal without burning through a copper tubing. Especially for those of you who are new and aren't really used to the two brazing. And so just know, you know your tips, know your torches a lot of times.

The tip manufacturers will actually tell you what their desired psi setting is on the oxygen acetylene tanks, so by all means follow what they tell you. But if you're gon na make adjustments make them at the regulator instead of at the torch handles, are some of you still going to make a small adjustments at the torch handles? I'm sure you will I understand, but in general you want to make those adjustments at the regulator. Another question that comes up is, you know: there are different types of regulators even and so in general you want regulators 15, psi delivery. Regulators are generally what we use for our work.

That's the right regulator, because we don't really need more than 15 psi output, and this is always safer to use something. That's gon na limit its output to the job that needs to be done. So, in general, a 15 psi delivery. Regulators is a good practice for of your average HVAC.

Our service technician to have another thing to mention that is sort of a pet peeve of mine is guys using Crescent wrenches or channel locks or anything other than a refrigeration. Wrench or a dedicated wrench for opening their tanks, so what I suggest is just keep a refrigeration wrench on your tanks and so, if you're gon na open and close them. Obviously, you know in most cases your oxygen or since a most cases been a lot of your oxygen will have a regular handle, but your acetylene will have a stem for opening and closing and that stem. If you use channel locks or any sort of two sided pliers, you're gon na run, you're gon na run the risk of breaking it off and I've seen a lot of guys do that so use a refrigeration, wrench or a dedicated wrench.

For that purpose. Also, one of my other pet peeves is guys who use a nine-minute. I know a lot of you you're gon na you're gon na hate me for this, but guys who use cigarette lighters to light their torches instead of using a proper striker. A striker is designed for lighting torches.

A cigarette lighter your fingers are very close to the outlet of that torch strikers are inexpensive. Keep a few extra in your truck, keep a few extra in your torch kit, but just use a striker for pete's sake. It's designed for the purpose they work right and it's a lot more. In my opinion, it's a lot safe, there's a lot less likely you're gon na burn your hands and easier to handle as well.

I mean you're, not gon na use a cigarette lighter. If you have gloves on so, if you're raising like you should be with gloves, then you're not gon na, be able use a cigarette lighter anyway. So just get a striker. You Strykers there, that's a it's better! It's the way to go so once you know you have the right tip and you set your you set your regulators to the to the proper pressure, so three and three or five and five or seven and seven generally, five and five is probably the most common.

Once you get that all set now you're just time to go ahead and light your torches and, like I've, mentioned the proper way of doing that is to open the acetylene first halfway light. It then open your oxygen and then get them both open until you have the proper flame balance, which should be a neutral flame, and so the way to know that you have a neutral flame. If you look - and this is we're looking at photos - are actually doing it as a better way to do it. But if you want to look up, the two different types of a flame are actually there's three different types of flame, there's, a neutral flame which is the flame we want to use in most cases, there's a carbonizing flame which is more acetylene than oxygen.

And that's going to be you're gon na have like a secondary tip, so you're gon na have that you're gon na have the flame tip and then you're gon na have another kind of tip that fans out beyond that. And then you have an oxidizing flame, which is you go to neutral and then you keep adding more oxygen. So some photos will kind of show you the difference in of neutral and an oxidizing. But it takes a lot of experience to tell the difference between an oxidizing flame and a neutral flame, which is why a lot of Tech's end up braising with an oxidizing flame, which is bad and oxidizing flame, has poor wedding properties.

And so what will happen? Is it makes it more difficult to braise properly with a with a oxidizing flame? So what you do is, is you start with a carbonizing flame, so you start with more acetylene, and then you slowly set in your oxygen until that second tip just barely disappears, or maybe just a little bit of that second tip still appears again hard to describe On radio, just look up the difference between an oxidizing, a neutral and carbonizing flame, and the main thing you want to know is a little bit of carbonizing is okay: neutral is even better. That's like a dead, perfect flame oxidizing is bad. The reason why carbonizing is better than neutral in some cases is that it just proves that you're definitely not oxidizing, because oxidizing equals not good. Another thing to mention, and again I'm talking about aux acetylene brazing here, but another thing to mention is what makes brazing different than soldering so just quickly anything above 800 degrees Fahrenheit is considered brazing, anything below 800 degrees.

Fahrenheit is considered soldering. We still call its solder a lot of cases, so we'll call it. You know silver, solder or blue board, we'll call it braze rod, but sometimes we'll still call the actual raw solder just commonly, but just because you're, using something that someone calls solder doesn't make it soldering. It's the temperature that makes it soldering versus brazing and the techniques are different for the two, but just don't get don't get too hung up on it being called solder versus brazing rod, because you're gon na hear those things interchangeably said in the trade.

But you do want to think about it, specifically what rod you are using, and so, if you're, using copper to copper, you're gon na see a few different rods commonly used. You're gon na see the cheapest rod is foz, copper, which is just made of copper and phosphorus, and compared to copper, are brazing. The phosphorus acts like the fluxing agent, if you will, and so Fonts copper does work, but it has a higher melting. It's it's just not as high quality.

The best bet is to use either 5 % silver. A common brand would be SIL, plus 5, so 5, 10 or so fast 15. We generally use 10 %, and that's then those numbers are the percentage of silver. That's in the solder, so it still has phosphorous copper and it also has silver and that's a that's a common product to use when doing for cop to copper.

If you're gon na go from copper to brass or or you're gon na go from copper to steel, then you want to use a higher silver solder product. In general I like to use a cell fluxing, so a flux core product or a flux coated product. That's high silver, that's designed for that purpose and, like all things in this business, it's best to just read it's best to know the products that you're using and know what suits a particular job. So that way you use the ideal product for the job you know.

Could you potentially use so fast, 15 4 going to you, know, copper to brass yeah. You probably could but instead use higher silver and something that you know is a flux, core flux coat. It just gon na be easier for the job. Now we're not talking about flux, we're not talking about rod.

Selection, we're gon na do a whole nother episode. Hopefully I'm trying to get Harris on to talk specifically about those products. So if I just said something wrong, they're, just free of me, but the point is: is that we're talking copper to copper in general and that's where you can use phosphor, although I don't recommend it 5 % silver commonly called sylla's, 510 percent silver or 15 % Silver before you actually apply heat to the actual connections, you want to make sure to consider what you're, what you're working on. So if you have something that you want to protect like a compressor or a line dryer or especially an expansion valve with an expansion valve, you want to make sure that if the bulb is connected to the line and it's close to where you're making a joint, You want to go ahead and just remove the bulb altogether.

In most cases, the bulb is gon na, be a ways away, but just still keep heat away from the bulb. Keep heat away from the expansion valve itself keep heat away from the compressor. So you don't burn the paint, keep heat away from line dryers and mufflers and accumulators and all those things to make sure a that you're not going to damage them, but be that you're not even gon na damage. The paint.

Because if you damage the paint or the coating, then it's gon na be more prone to rust, so you want to use either wet rags or other heat trap products to keep heat away from those those devices whatever it is that you're soldering in service valves is Another example: it's always a good idea to have the Schrader's out of the system when you're brazing, so that what you don't have to worry about either damaging the Schrader's. But then also so you have full flow in and out of them, so that lee makes it easier to flow nitrogen probably mentioned that before, but get your traders out of the system. You don't want traders in when you're raising so now you've done everything properly. You've got your.

You understand your equipment, you selected the tip properly. You set the the PSI on your regulators to the proper setting. You've got everything. Nice tight and clean you've made sure to follow proper practices, so you're not getting any junk in your lines.

You've got the proper solder in your hand and you're ready to work all right. This is where you want to have some some damp rags beside you. Maybe a set of channel locks in case you have to handle something really quickly. That's hot.

I don't know just a good idea to have everything all laid out and prepared make sure that everything is protected. All around you, you've made all your considerations for anything that could catch fire. You've got your fire extinguisher right. There you've got your safety glasses on you've, got your gloves on you're ready to work.

Okay! So now here's how you actually make a proper braze joint. The first mistake most common mistake that newbies make when they're brazing. Is they don't get it hot enough because it takes it takes several seconds. You know, generally speaking, if your, if your flame is the right size for the job, it's usually gon na take six seven eight seconds to heat it up in the first place, so it gets hot enough to actually start applying the the rod to the to the Joint - and that was just an estimate on my part - I've never actually counted.

Let's, let's count see how long that takes one two, three, four, five, six yeah. I think six seconds that sounds about right and I just wanted to put you through that that board um. You listened to a podcast anyway, so clearly you have a pretty good attention span. Six seconds sounds about right before you want to start actually, even thinking about applying solder.

Now, back in the day, my instructor at trade school would say, get it deep red, so get it deep red. He would call it dark cherry red, but don't get it bright red. I don't. I don't that's not always necessary.

It depends on the type of rod that you're using, but generally, if you're using you know, 10-15 percent silver. I find that it's not necessary to get it that red generally, I think you're gon na get it that's a little too hot, but you do want to get it hot enough, so make sure that you're getting it hot enough, but where you first want to put Your flame, so if you're thinking of the tube going into a coupling, so you have the male part that is the tube and that inserts into a coupling, so we're focusing the tube here. You want the solder to be drawn into that fitting, so solder doesn't just bridge the edge. That's what a lot of new technicians do.

Is they keep? They don't get enough heat on and then they just keep trying to like melt bits of solder on the edge. You want the basada to be drawn into the fitting. So the first thing that you do for the first couple seconds is you get the actual pipe hot so outside of the fitting itself, so you're actually pointing the flame? If you can imagine this you're pointing the flame back at the fitting and you're and you're really focusing on the pipe through your driving heat through that pipe into the fitting and then once you actually start applying solder now you're pointing it back the other direction. So the heat is now on the actual coupling itself, so the female part - and it's pointed back at the at the actual, copper tube so and in Harris - has a lot of really good photos on this.

If you want to look up the the Harris website, you can find some photos on exactly what I'm saying, but just imagine the the tube. The tube is the male part and it's going into the female coupling. So you start by pointing it at the coupling focusing the heat on the tube that way the tube is getting hot and heat is transmitting inside that coupling. Then you start applying solder, and now you point it back the other direction, with the heat concentrated on the actual coupling to make sure that you suck as much solder as possible into that coupling itself, then once you get done, you want to, you want to do And this is some people will tell you differently, but in general I want to make sure that you have a good fill it.

That's the term that we use are a cap on the actual end of it, to make sure that you can look at that fitting and know that it's not leaking. So, where that, where that coupling covers the copper, you don't want to see any gaps or crevices around there, you want to just make sure that that's nicely coated and a cap of rod only once you know that you've pulled solder into that joint you've pulled the Brazing rod into that joint, so it's sealed the whole thing, so you seal the whole thing and then you make sure that you have a nice cap on it. Then that's when you take your you, take your mirror and you make sure that it's all nicely sealed. There's no cracks, you do all.

You always use a mirror and look at the entire fitting before you do anything else and now let it cool. Naturally, now this whole time you've been flowing, nitrogen. The very very low amounts you've been using two to two to three cfh or cubic feet per hour of nitrogen, so you've been flowing at very low rates this entire time. Now let it cool, naturally with the nitrogen flowing - that's gon na - do a much better job of preventing any carbon from building up inside the lines, because that's the reason that you do it, that's the reason you feel a nitrogen.

I didn't talk about that because we talked about this in other podcast. We've already talked about why you flow nitrogen, but that's why you do it? You do it so that you don't build up carbon inside that line, because if you look at the outside of the line, you get these nasty carbon flakes on the outside. If you don't have nitrogen flowing or some inert gas flowing through that line, then you're building up that same nasty carbon inside there, which can go, get stuck in electronic expansion valves or cap tubes or whatever else, which is all nasty stuff and there's lots of reasons. Why our our forefathers in the trade didn't used to worry about it as much as we need to now and I'm not gon na go into all those.

But it's an important thing and it's something you need to be doing as much as you possibly can. But in addition to that, let it cool with the nitrogen still flowing, don't jump straight to throw in a cold rag on it or anything. Just keep moving down the line and making more joints. Then, once you're all done, they've all cooled, the last one is sealed.

The nitrogen is shut off. That's when you do a final inspection on all of them. Make sure that everything looks nice and sealed, and now your nitrogen pressurize back up and you do a bubble test on all the fittings that you just created before you go covering them an RMI flex or anything. I've had a lot of installers.

Tell me you know: well I'm just that good. I know they're not gon na leak, pressurize it up with nitrogen, depending on the system. That's gon na dictate how much pressure you use, but pressurize it up with nitrogen to the into the safe level and bubble test. All those joints and check them all with aamir make sure that you've done you've done the right thing, because this is quite a.

This is quite a thing I mean setting this all up and flowing nitrogen and putting on your safety gear, and all this you want to get it right. The first time there's nothing worse than not getting it right, the first time and again for the newbie. The mistakes they make are not following proper safety procedures, not reading the manual further for their torches and making sure that they're using the proper tip and then ensuring that they're using enough heat to get the job done quickly. But what damage is probably more components.

You know reversing valves being the worst and in Florida we have a lot of heat pumps. So we have these reversing valves and they've got four connections on them that are really close to each other. Again. This is an episode on how to do a reversing valve.

If you've, if you're gon na go, do a reversing valve talk to an old-timer and they'll, give you some some tips to do it before you before you go jump into doing that job, expansion, valves and compressors and all and line drivers, and all these things that Can be damaged by by too much heat. It usually doesn't happen because there's too much heat one time, it's because they're on again off again in and out in and out in and out with the torches, there's no reason to be in and out with your torches. You regulate the distance between your torches and the fitting just in order to control your heat and a lot of times. You do this because you may have a little more heat than you need and so you're backing off just a little bit, because this is sort of natural like if you're, using the same type of tip and the same flame in general.

To do your liquid line and your suction line say on a new system install if you have the flame set perfectly for say a 7/8 fitting well, that same flame is gon na, be a bit too much for 3/8, so either you can alter the time. So you can just work more quickly or you want to back off a little bit to make sure that you don't overheat the fitting, because you don't want to get it as soon as you start to see a fitting or copper or anything start to turn bright Red or even cherry red, I don't think you need to get to that point. You want to back off so that you're not you're, not overheating it, but you don't want to back off completely. I see so many texts that look like they'll start to braise and then they'll like back off and think about it for a little bit and then go back in damaging.

Something like liquid line service valve or a suction valve is a factor of how much heat are you getting on it and then how long are you getting the heat on it? So, first of all, you know by using wet rags or some sort of heat trap, product you're, keeping it cooler. So that's an important part, but then also you want you don't want to use way more heat than you need, but you also want to make sure that you get on it quickly and get off it quickly. It's done as quickly as you can. I see guys, you know they, they use a little rod and then they take the mirror and they check, and then they use a little rod and they take a mirror and then they check it's not how that works.

You'll notice, I didn't over stay like all the techniques of holding the flame and all this, it's very simple. You start put the most of the heat on the pipe, pointing towards the fitting once it once you get to the point that solder starts to flow, then focus you eat the other direction, don't overheat any one spot and burn a hole through it. That's all you need to know really don't overthink it on big, copper. Obviously the larger the copper is, the more you have to move the flame around to distribute the heat all the way around and while you're brazing, but but you don't want to be moving the thing all over the place and inexperienced brazier is a guy who's constantly.

Moving his torch all over the place, it's just not necessary. Obviously, if you're starting over heat a section, then you move it a little bit or if it's not flowing in one section, you need to move the torch to get heat into that section so that you can flow but get in get out and get it done. And the best way to do this frankly for those of you who are new to the field, if you're apprentice or whatever just there's, no there's no replacement for getting a set of torches. Knowing your torches reading up getting all your safety equipment, getting everything ready and then just plant a bunch of pieces of copper tubing in your yard and start going to town and doing all sorts of bracing.

Any technician who talks to me and says all. I want to learn more about brazing, I'm not good at brazing. The question to ask is all right: well one, if you practiced well, I haven't had much of a chance. What do you mean you haven't and much of a chance I'll give you as many fittings and pieces of copper as you want, go home plan them in your yard, yeah that make sure to follow proper safety procedures, use glass.

You know safety, glasses and or goggles and gloves and go at it, though have you know, learn practice, that's what it takes just practice, but don't go moving your torches all over the place for no reason and don't keep going in and out on on the piece That you're working on the only reason to back off is if it's overeating I feel, like I'm saying the same thing over and over, but this is really what you need to hear if you're new to the business. So, finally, once you've applied nitrogen nitrogen pressurised bubble tested everything check everything thoroughly with a mirror mirror a flashlight are a great thing to have for checking all of your fittings make sure you don't even see any little micro bubbles. You know you're just checking everything really well now: you're ready to go ahead and pull your micronic vacuum, and while we do not use a micron gauge to check for leaks, that's not its design, it does help you check for leaks. So the final step in a properly performed brazing job is to make sure that you have no leaks.

Nitrogen is layer number two layer number one is visual inspection, nitrogen and bubbles are layer, number two and then layer number three is pulling a micron vacuum once it's all done. You valve it off at your core tools, because that's you know. We've talked about this ad nauseam if you're cool record tools connected and your micron gauge is connected to the side of your core tool, you valve those off and you make sure that it doesn't. Your vacuum doesn't keep rising and there's different reasons why vacuum can rise.

It can be moisture, it can be leaks, but you want to make sure that it doesn't continue rising above a certain decay rate again, another podcast, but that helps you ensure that your brace joints are tight. So in in final final things to go over here. Safety is very important. You want your all of your brace joints to be visually confirmable as not leaking, which means that they have a nice cap around the whole thing, but the cap is not what seals your brace joint.

What seals your braze joint is drawing solder into it, don't overheat a single spot, but that just takes looking at it. Most guys, who I see, who are poor brazzers, are nervous bracers, so they're always nervous that they're gon na burn through the copper you're, not gon na burn through the copper. If the copper is not getting red yet so you don't have to worry about that. As long as you have the proper heat you're, also gon na reduce the chances that you're gon na burn through your copper yeah if you're using a gigantic torch tip, you know and you've got it set to.

You know twenty twenty on your regulators and you're just dumping tons of gas at it and you put that trip with them a quarter-inch line. Well then, yes, of course, you can melt through it. But if you're, if you're sensible about this - and you know what you're doing you're not gon na melt through copper, most technicians don't apply enough heat flow, nitrogen, don't pressurize with nitrogen and while you're brazing make sure to purge nitrogen first before you flow to make sure That you've displaced, all the atmosphere, is possible only braze on an open system so meaning that there has to be a port open somewhere to braze. Otherwise, when you heat it's going to become pressurized, don't unswept fittings! If you can help it, because you run the risk of setting the wheel on a fire and creating a mess, always think about the space that you're working in use, proper safety equipment when you're setting your regulator set them to the same pressures generally, five and five.

But can in some cases be three and three seven and seven may be in some rare cases. Ten and ten read your manufacturer's information change tip size based on the job that you're doing you don't use the same tip for a 3/8 line that you use for a two and a quarter line or two and 3/8 line users use a separate tip for those.