Brazing Techniques

This video is a Kalos Services training class about basic Brazing Techniques. The class was primarily aimed at commercial pipefitters and is the first in a series of classes.
The words "brazing" and "soldering" are sometimes used interchangeably, but soldering really occurs at temperatures below 840 degrees Fahrenheit, and brazing occurs at temperatures above 840 degrees. We may end up brazing or soldering when joining or repairing metal tubing; to join metal tubing, we need to heat the base material to the point where it's hot enough to melt a brazing alloy and draw it into the joint via capillary action. Some technicians are afraid to burn through the pipe and end up not heating the joint enough to draw the alloy in, especially if they mistake cupric oxide formation for a burnt pipe. Repairing requires us to create strong bonds over leaks by patching them and requires a different technique from joining.
Copper-to-copper brazing is one of the most common and straightforward pipefitting tasks, as it uses a phosphorus-based alloy and does not require a separate flux. You cannot use phosphorus-bearing rods when brazing or soldering copper with dissimilar metals, as different base metals have different properties. Each metal will have different compatible alloys and fluxes, conductivity, and melting points. Copper has high thermal conductivity (relative to other metals) and a melting point of around 1950 degrees Fahrenheit.
Alloys are filler metals, and we want to pick ones that are appropriate for the base metal(s) and as ductile as possible; alloys with higher silver content tend to be more ductile than ones with lower silver content. Flux helps the alloy flow and also keeps oxides from forming on the base metal.
Oxides form on the base metal when oxygen combines with the base metal; in copper, temperatures above 900 degrees allow oxygen to combine with copper and form a black scaly substance called cupric oxide. These oxides make it difficult to create a good joint, and oxides inside the tubing can come off the tubing with POE oil, which makes the oxides clog filters and screens. Along with using an appropriate flux, purging the system with nitrogen before brazing and flowing nitrogen while brazing are the best practices to prevent oxides from forming in the tubing. Nitrogen displaces oxygen before brazing and keeps it out while you're brazing.
To be safe while brazing and soldering, we need to keep a fire extinguisher handy at all times, keep the work area clean, and wear proper PPE (including safety glasses of an appropriate shade). Oiling regulator threads can also increase the risk of combustion, and it should never be done.
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[@luiscardona9608]

Gotta love the free school lesson.

[@MR-backup]

Unfortunately this is one is doomed to become an archive; zoomlock is the future :\

[@eugeneeugene3313]

Wow, just wow. The guy is super professional!

[@armaletalia3254]

Always appreciate free knowledge. Thank you.

[@keithjordan5688]

I’m always learning something new. I’ve been brazing for around two years now and didn’t know you can braze dissimilar metals.

[@MegaManGabe]

I’m just starting my career in HVAC, and these videos are very helpful. So thank you!👍🏼

[@courtney2878]

Wish I found this lesson 3 days ago as I just finished my first brazing project. Insanely satisfying process lol.

[@salehfarman9054]

This guy is super professional! Thank you so much

[@jproper]

I'm a 10 year tech and just popped in to see the tips. Good video as always🤘

[@gsmboutiqueable]

Thanks for sharing your experience with us!!!

[@dr00andrew]

Brazing is easily the most satisfying part of the job. Nothing like getting a nice clean joint all the way around with a nice crown filling in the edge. Ive also found that placing an inspection mirror underneath the suction line service valve while brazing ensures you fill the entire joint the 1st time around. Since you cant see underneath when brazing, the mirror allows you to see you have filled in the area you cannot see with your eyes. Then you can move around and get the spots you can see

[@La2venida]

What tip size you use and pressures

[@winstagram1785]

Great tip!

[@AlbertFrederickLarun]

Brian always gets me motivated to crush HVACR!

[@ApartmentMaintenancePro]

Love this stuff Bryan !

[@samuelg3586]

Outstanding class brother

[@mikelsbug817]

This is very informative. Thank you

[@SoullessProductions]

As an appliance tech dealing with refrigeration this helps. Was an Auto mechanic for years then went appliance and have to deal with refrigeration. I was doing things and never really understood why until i watched this video.

[@dioncurtiscurtis3188]

My supervisor must have called about a few of us 😂

[@youngjedi5599]

I know right. He seemed pissed.

[@HermanMeyers-k4x]

Small wet rags around each tube on evap coul and on txv's pull caps and scrader cores out. Rap driers close to drier body. Make sure flame never hits the txv power head . Always braze the suction first. Purging is good on new hard drawn pipe if you can't put 5 psi of nitrogen purge with nitrogen and use the vac pump. You will use alot of vac pump oil. Old line sets have to be flushed with rx11 or liquid flush. Use lots of nitrogen with l liquid. Use clean up driers if it's a bad burn. Acid way works also. Cut flare off and braze. Prevents headaches. On flares on mini splits you can cut flares of at the evaporator and swag with one braze joint. Flow nitrogen. Through. I always use 400 psi or more for pressure for leaks. Flare at a mini splits I use leak lock from high side chemicals at the condenser. Only rubbing alcohol can take this off. You do that at the caps to. Most techs won't know this and this stop the leaks on top of service valves and brass caps. So leak detection can only be needed at the evap return bends or the flare on a bleed externally equalize txv. Last would be at the condenser rubbing on the bottom of the pan. A coils that are old or slant have sheet metal and not aluminum. Some installers will not pull the new coil out of the case to make sure nothing is rubbing. That will cost you time and material. A little of arm flex or cork tape will fix that. Always use wet rags on plastic drain pans or condenser pads. Good vacuum of 1000 microns will make your system super dry and absorb refrigerant alot more easy!!!!! When in doubt on long Refrigeration lines use another vac pump on evap coil were sollonids valves and txv's are 1000 microns no less. This will make the competition die. If you need or don't need use leak sealer from Refrigeration supply distribution from ???? Will only bullet proof the system even better!!!!!

[@imteyazsiddiqie8186]

Very good lessons 👍

[@fixitmekanik412]

great video, thanks for sharing!

[@abdulhvac2395]

Thank you very informative

[@yorkrojas1452]

Thanks a Million!!

[@Shawn_RHVAC]

Work with Mr. Taylor on a job site issue. Guy is amazingly smart. Lol. Great guy, great team Kalos has and love all the videos you offer. Any chance you have any training on Novar systems.

[@Badtxv]

I wish I could've gone to this 😢

[@abdulfattahkarimi8982]

Great, video. Thanks for free teach. I have a question. Some body soldering HVAC lines with Staybrite 8 and says it is stronger, cleaner and faster than cooper brazing. Do you think is it the right way and stronger than cooper to cooper brazing?

[@davetysdal5442]

Wondering about the legality of S 8 also. Looks like it's frowned upon in residential HVAC? 10,600 psi pressure rating on the SDS. Harris says it's OK for refrigeration.

[@hvacinstalacije1985]

Regards from Bosnia :)

[@26212269]

Awesome 👏👏👌👍

[@scottjones7279]

And when is part 2?

[@Elisummit845]

Finally got something to add to my telegram channel 🤣. Thanks Bryan

[@jaymz0074]

Man good stuff

[@Shawn_RHVAC]

Are you going t on moist the remainder of the class??

[@wagnergitirana]

Very informative video. Now, what do you think of the use of RLS fittings and the cordless tool ? I tend to compare the plumbing PEX fittings from Uponor and the expansion Milwaukee cordless toll as well. My question is : is the RLS jawkit8 tool along with its copper fittings a permanent substitute of brazing torch ? I’m talking about exclusively for residential applications. I will start HVAC school soon here and I want to focus on residential only. Your input will be really appreciated. I’m a new subscriber here . Thank you !

[@winstagram1785]

Short answer - they are a game changer for multiple reasons and so far seem to work great, but nobody knows the real world lifespan of the gaskets. The biggest difference in HVAC vs Plumbing is our pressures and temps fluctuate. The biggest resistance to this is the fact that a properly done soldered joint is 100% going to last. I think the time saving and risk reduction is worth it and would use press fittings exclusively if I was a tech. -A certified factory support rep and trainer for 5 manufacturers.

[@lostcause4517]

Matthew Taylor is the man! I wish Walmart would of been able to keep him 😒lol

[@jasonthurston799]

Doesn't brazing's extreme heat alter the properties of the copper and weaken it. Like it anneals if it wasn't already annealed? I've been hearing that soldering creates stronger joints when you use the right kind of solder.

[@mikafoxx2717]

Maybe, but never is it the annealed copper bursting that causes leaks, it's cracking or rubbing through or some such.

[@HVACRTECH-83]

Shouldnt have any issues using 15 with flux on cop to brass

[@andrewd762]

Can you use CO² as a purge gas instead of nitrogen when brazing refrigeration pipework? Thanks for the videos, I've found them very informative.

[@HVACRTECH-83]

Co2,although you can get dry c02, it's much more expensive than nitrogen which is why we use it instead.

[@HVACRTECH-83]

So, yes you can lol but I'd save c02 for the keggerator. Stick to nitrogen for brazing

[@MR-backup]

How did you exponent your "2" like that?

[@andrewd762]

@@MR-backup I stuck my finger on the number 2 and held it. I then get several options like ² and ⅔ and ⅖ for example. I'm using the gboard keyboard thing on Android so it might differ for you.

[@andrewd762]

@@HVACRTECH-83 The reason I was interested in using CO² instead of nitrogen is that CO² is stored as liquid when it's in a cylinder whereas nitrogen is just compressed gas so you get a lot of CO² in a very small cylinder which means it's more portable. To carry the same quantity of nitrogen you need a bigger heavier cylinder. I just wasn't sure if using CO² would result in an inferior braze or weld joint.

[@davetysdal5442]

Wondering about brazing safety also, so you don't start fires in houses while brazing. Dangerous? ACR pro press much safer, but $$$$.

[@mauriceshumock1869]

I do residential appliance repair and perhaps it’s a different ball game but I’ve never seen anyone run nitrogen when doing any brazing or soldering. They don’t even mention it at the manufacturer trainings. Now I wonder if the oil we work with doesn’t cause any issues if we don’t run nitrogen because no one in this industry ever talks about it where I’m at. We mostly work on R134A and R600A. The capillary tubes may be smaller so I also assumed we don’t do it because maybe it will bubble the joint. I’ve also been doing it without running nitrogen for about 5 years and never had any problems that I’m aware of. I’d appreciate an opinion if you have one on that.

[@whitesheatingairappliancer7101]

How are you brazing aluminum to steel or copper to steel?

[@mauriceshumock1869]

@@whitesheatingairappliancer7101 I’ve never seen a aluminum to steel connection but I tried it once for fun and what worked for me was Multisol from solderweld. It’s tough for me to use but it also works for steel to copper. I only use multi sol if I don’t wanna apply too much heat. My go to for steel to copper is Sil Sol 56 and for aluminum to copper pipe connections I would only use Al-Cop braze. All from solderweld and they are all easy to use except MultiSol, at least for me

[@mauriceshumock1869]

@@whitesheatingairappliancer7101 steel to copper was difficult for me for a long time but I recommend that you try Sil Sol 56. You heat up the copper a little bit and then focus the heat on the steel next to the joint until the steel is red hot, it should melt in around the joint perfectly. It never leaks for me if I do exactly that and let it cool down by itself without putting a wet rag on it. And to be honest, I’ll let even put Stay Silv brazing flux on the joint before brazing. It’s unnecessary but it works better for me.

[@EarlHayward]

Are you running oxy-acetylene or just acetylene? I use oxy-acetylene and a higher silver alloy and do the joint quick, so that might be the reason (if not oil)… I think gthose running air acetylene, with say a TurboTorch tip (probably oversized), are placing a lot of heat all at once causing much more oxidation inside…

[@mauriceshumock1869]

@@EarlHayward I just use acetylene with a fairly small tip. The connections I make are smaller. The only other issue I’ve had is actually focusing the too much on the steel and under heating the copper. I’ve also had best results with the high silver flux coated rod. If I heat and clean it properly the joint comes out a shiny silver all the way around indicating that it’s unlikely to leak. With these joints I avoid cooling them off quickly. Just about every time I’ve done that it ended up leaking, sometimes it would take 15 min for the micro bubbles to form.

[@HVACRTECH-83]

I think we all got what you meant at the end,lol, but in case anyone didnt know, oxygen is not mostly what our air is made up of, its only about 21 % of our atmosphere. Nitrogen is most of what we breathe at around 78% then the rest is c02,argon,neon

[@lifjimbo7251]

He said Nitrogen is mostly what's in our air lol

[@luke9129]

❤❤❤

[@mox2766]

2nd year.... and work with guys 10+ years in the trade... and all these guys do is put caps and they get mad at me because i focus on penetration...

[@KoshYTGC]

I did this in grade 7

[@HermanMeyers-k4x]

This isn't just HVAC only my friend

[@conqwiztadore2213]

Wow I learned more in 15 minutes than the 32 hour course I had to do for med gas. Just kidding, (only a little)