All right, so I'm gon na show you how to make a patch in an aluminum coil, and this is actually gon na, be the first time that I even attempt to do this within the finstock on a coil. But I don't see any reason why it should be difficult using the alloys, all rod and the alloys all flux from solder weld which comes in their new kit. That has all the different Sauter's that you're going to need. Soldering and brazing alloys that you're going to need for air conditioning refrigeration application, but I want to show you from a real practical standpoint.

We do get holes inside of aluminum coils from time to time, both of operators and condensers microchannel coils are made of aluminum and in a lot of cases, we need to make a patch whether it's just to get a temporary operation or whether it's because we want To make a permanent repair - and I'm gon na show you how to do this with this rod, it's very easy, but the technique is a little different than what you're probably used to all right. So the first thing I'm gon na do here is: we need to pull a nitrogen through this coil in order to keep carbon from building up when we are brazing when I am working with the alloys, all you're, probably not going to get hot enough for you To actually build up any carbon, I still like to do it as just a habit, because when you purge nitrogen through and then you flow it, it just helps displace anything from coming into the system. It's gon na make it less likely that you get contaminants in the system just a good practice. I know a lot of people say you don't need to do it and I understand that.

But the first thing I need to do is cut this off. So that way I can actually flow through, because you can't pressurize with nitrogen a neat little trick is you can use either? One of these cut brushes like I've, got here on a drill or you can use a round brush to clean up top or makes it a lot quicker. I've seen guys do this before, but Eric Meli. Does it all the time - and it is actually really nice - cut a piece of copper on a compressor cut, a line dryer or whatever you're gon na cut out it's just nice to pre clean it.

So that way, when you cut it, you're all ready to go and it's a heck of a lot easier than the using Emery cloth fan cloth. Whatever you want to call it there, you go cut this off cut it out, as my mother used. To always tell me he's yelling at me just kidding my mother would never yell at me. I wouldn't be nice.

That's cut in half now we're gon na. Take our nitrogen and we're going to flow it through this coil. Whenever I flow a nitrogen, I just want to make sure that it's coming out the other end at a very slow rate, where you can just hear it when you put it up against your ear. I'm actually in this case, because we got a decent amount of volume here, I'm gon na purge through I'm gon na put it up into the purge zone.

First, it's going through the metering device still, so it's a we're gon na put it back into the flowing nitrogen zone. Yep barely here come on out. Okay, now we're good shape. Alright.

So now I'm gon na make a hole in the coil which is gon na. Try to replicate a rub out, which you know it's tricky to do, but I'm just gon na take an awl wack it into one of these tubes. I mean I've done it on the you bends. I've done it all over the place on these coils, but we're gon na just do one right here.

Right in the center of the coil got a little piece there. So there's a lot of different ways. You can go about getting the fins away from here and in some cases, guys will just say, melt them away, but they can kind of get in the way a little bit. So I like to take either a flat blade, screwdriver and needlenose pliers and just kind of work them away from the area that we're gon na be working just a little bit.

So there's our hole all right, so you can do this with an ox acetylene torch. You just have to you know, use a really soft flame and hold it back aways. I prefer to use a small tip on a turbo torch air acetylene. This is a number 3 tip, and this is about perfect for what we're gon na be doing here.

I'm using the alloy saw product on this alloy saw is a low-temperature rod and it works best on thin. Aluminum alloy braze also works, but you have to be a lot more careful in the thin aluminum. It's more likely that you could man. I have an accident on your hands and burn through it.

So with this strategy, is we heat up the end of the rod? If we put a little flux on it, we heat up the work area. We melt the flux onto the work area, we keep heating it until we see that flux go clear and then it will first at first the flux will cover the hole and then it will open and once it opens up, then it's time for me to start Applying rod - and I just keep my heat on it until I get my rod, melted and then I back off. That's it it's a low enough temperature that, as long as I don't do anything stupid, I should be able to do it. Just fine.

I've done lots of aluminum cans, it's all about heat control like most things and I've used a lot of different aluminum rods over the years, and this is the one that I've been the most successful with all right. Another thing to keep in mind so we've got our air acetylene torch. A lot of guys have asked me about this. As they've watched these videos, I really like both I've used ox acetylene.

My whole career air acetylene is great because it's so simple, you don't have to think about it. When you light it, you just open it up and you hit the self-lighting now. One thing to keep in mind is - and this is a mistake - the guys make you want to make sure that this is really snapped in and you don't really want to modulate the heat you modulate the heat by choosing the tip more than anything else. So I see a lot of guys trying to modulate the heat you can burn back down into the tip and then that becomes dangerous.

So you just make sure that it's in place you open it up an hour, we're cooking with gas as they say so. The first thing that I do is I heat up the tip just a little bit and I get some of my flux here. You can see. I got flux now, I'm gon na keep the heat the area just a little bit.

Now the flux is gon na run into the hole all right so now the hole. Now, if you look at the hole, the hole is covered up, the hole is completely covered up with flux. Currently so now I'm gon na go back in and I'm going to melt that flux and now I'm not going to back back off until I get it done and you can see the fins are starting to melt away a little bit. That's okay opened up a little bit now, I'm not melting my rod onto the work area.

That's got all the rod I need now. I'm gon na add a little bit more flux to it. I'm not quite happy with my work there at the bottom and that's okay. Gon na add a little bit more all right, so we've been flowing nitrogen.

This whole time come on in take a look now: we've got a decent-sized hole in the fins here and a lot of people would say why would you ever do that? But in a lot of cases, I've got to get this coil sealed in order to get some of the air conditioning, especially true in commercial applications and residential applications. You would do it again to get somebody through the night that sort of thing, but a more practical application would be if you had a rub out on a u-bend or on one of these tubes and I'll show you that as well right now. But you can certainly do it in a coil like this we're going to pressure test both and bubble it here in a little bit so that you can see the effect of that and make sure that it is holding under 500 psi in nitrogen. But now we're going to go ahead and make a hole on one of these.

You bends all right, so we do need to once it cools off. You need to clean it off with a little bit of water. I've got a little tub of water here and a brush, and that certainly isn't pretty, but you can see how it's an exact color match for the aluminum and it definitely covered that hole and, like I said, will pressure test it inside of a coil. It's never gon na be a pretty patch.

It's just sort of a nature of the beast, but I'll show you what it looks like on a rub out here. The first thing to know is I made this hole with an awl, and so an awl is gon na push material into that you Bend. If I were to cut this open, you would see that material going in, but one nice thing about this solder is it does kind of make a nice even patch on the top. It doesn't pull in and get into the joint, which is important if you're trying to patch a rub out a lot of people would say it's better to cut that part out and start over on a u-bend aluminum coil, that's not really practical.

So this is really a great option for that. So the first thing I'm gon na do is I'm gon na turn on my torch again, I'm using a turbo torch. It's gon na heat up the rod. Again, you can use ox acetylene just use a small flame heat up.

The rod get a nice bit of flux, heat up the base material. Again, this hasn't been pre-cleared put the flux on it, so it melts into the hole. Now I'm gon na keep the heat on it and that hole is gon na open up and the flux is gon na go clear once that goes clear, then I know it's okay for me to start applying my rod and it's gon na go on like a Little glob, I don't need to move my rod all around it's gon na go on a little glob. I can back it up a little bit.

There we go now. I just keep it on there until it smooths out, and I get a nice finished piece there. We go. That's it.

If you look right here: you're gon na notice, the color looks kind of weird, and that throws a lot of guys off. It gets an even when it cools off. It turns whitish, but once you clean that off you'll notice that it's underneath it's the exact same color as the base material. So you really can't distinguish what is the solder and what is the base material and you do need to clean it off with a little bit of water and a wire brush like I'm doing here, because that flux is slightly corrosive and it couldn't hit it up.

If you want to get real fancy and you wan na make it look real pretty, can you take a wire brush and work it, but I've done a whole bunch of these. You can grind this stuff. I mean it's, it's just it's just as strong as a base metal, it's not stronger and it makes an amazing amazing bond. So there you have it now.

All we got to do is pressurize it up and I'll show you that it holds pressure with a little bit of big blue alright. So there you have it now. We just got to put it under a little bit of pressure test it with some soap bubbles. So I can show you for sure that everything held up alright, so you see, we've got it set in 500, psi take a little bit of big blue, see we get no no bubbles at all.

A nice seal down here. Take a look at this one. Real close, and that is at 500 psi and you can see we worked really close to the factory joints, which is also great but alloy salt because of the low melting temperature you're, not gon na compromise the factory joints as long as you're careful really really works. Great does the job exactly like you would expect it to, and it looks beautiful when it's done so that's its soldering using alloy, saw on an aluminum coil.

We did kind of a quick and dirty repair on the inside of the coil, and then we also showed you how to do it on a u-bend with flowing nitrogen and then pressurizing afterwards and testing with big blue thanks for watching we'll talk to you next time. You.