How to Patch an Aluminum Coil w/ AlloySol

In this video, we show how to patch an aluminum coil with Solderweld's AlloySol rod and flux. We use it to repair a leak in an aluminum coil as well as on a U-bend.
Leaks in aluminum coils are quite common in evaporators and condensers. Although replacement is common in those cases, we can also patch the aluminum coils by soldering them for temporary solutions or even permanent repairs.
You start off by cleaning the aluminum and purging the coil with nitrogen. Even though you may not work at temperatures high enough to promote carbon buildup inside the aluminum coils, it's still a good idea to flow nitrogen while soldering. Then, you make a hole in the coil (to replicate a rubout). You can pull the fins away from the area gently with a flat-head screwdriver or a small set of pliers.
It is possible to use an oxyacetylene torch with a soft flame for soldering, but it's probably going to be easier to use a small tip on an air-acetylene torch. (We use a #3 tip.)
AlloySol is a low-temperature rod best used for soldering aluminum instead of brazing. (AlloyBraze also works, but you'll have the be very careful with it, as it's meant to be used with higher temperatures.) We use AlloySol by heating up the end of the rod, putting flux on the rod, heating the work area, melting flux onto the work area, and continuing to heat the flux until it goes clear. The flux will cover and then open up the hole; when the hole opens up, it's time to apply the rod until it's melted. Some of the fins may melt away during the process; that is normal and will generally be fine for temporary fixes while waiting for a replacement coil.
Patching aluminum can be a permanent solution for leaks on U-bends. For patching U-bends, the soldering procedure is quite similar to the coil soldering procedure. Heat up the rod, dip it in flux, heat the base material, and apply the flux until it melts into the hole and opens it. When you apply the rod, it should go onto the hole like a little blob. Keep applying heat until you have a smooth finish. You can even use a wire brush after the U-bend cools if you want a nice, shiny finish.
Out patches passed the bubble and standing pressure tests.
Read all the tech tips, take the quizzes, and find our handy calculators at www.hvacrschoo...

[@NorCal-refrigeration]

Good video👍👍

[@L8NiteCoffeeSips]

What’s up cousin

[@mattluongo7763]

You make it look easy, like you said it's easy when you know how. I consider myself generally good at brazing but patching aluminum is not easy. I wish my company would invest in more products like what you have here. I've made some successful aluminum patches before with different rods but have also failed some too. My company has us use high temp epoxy with a heat gun, have had some hold and others not. Quick tip for epoxy products is to pull vacuum while applying it. I found it helps. Do you have an opinion on epoxy products and have you tried any? Thanks for the video.

[@L8NiteCoffeeSips]

Question for you, maestro. Could you also use a solder called “ChannelFlux” along with propane or mapp gas instead of oxyacetylene?

[@vernonroach918]

Thanks for the video....I have done a couple, like the product, but its melting point, even being low, is still too high for refrigerator or freezer evaporators that someone has taken a sharp object to, trying to defrost it....It can still be done, but blowing a hole in the evaporator is just seconds past the melting of the solder...I think the type of flux should be mentioned too.

[@blancoazcracker365]

i was told a long time ago by an old tech to sand where your going to cut first then you wont get the sanded off stuff into the pipe and also always sand back away from the joint and the coupling itself to get it shiny and will accept heat quicker as the oxidation will reflect heat and not absorb it as quicky,to this day is my practice

[@9873459872134234]

that is correct

[@crpth1]

Absolutely correct assessment. That's exactly how to do it. Curiously to clean a normal wound should be done similarly. Meaning always move away from the wound. So contaminants, dirt and debris won't come into the damaged/wounded area. ;-)

[@blancoazcracker365]

you dont need to keep the adjoining joints cool to avoid them coming apart?

[@robertnikstein1873]

This is a skill ...not to get compensated...wish my boss could grasp that...I'm ready to pull an " office space"....

[@alexzapata692]

Thank you. Great demonstration and presentation to go along.

[@johnnyprotalk3352]

Thanks for video I never braze aluminum and wanted to learn.

[@gene-khvacr]

Good workshop on the aluminum weld thanks for sharing 😎👍😁

[@borshardsd]

Ty always for the videos and I'm years late but man that camera shake when you are asking us to look =b No complaints and great content.

[@sandymitchell8182]

does it hold for awhile?? I punched a hole in my A/C unit outside my house, ( long and stupid story) trying to find someone to do this and refill with freon as all mine came out :). I'm wondering is this a temporary fix? or will this be good once its done? anyone can answer if you have a idea

[@gwp1ohio]

I have a small hole, HVAC tech said not possible to fix, need to buy new coil

[@97Napkins]

There all possible to fix but not practical for most residential units. Once there is a hole in an old coil the integrity off it is gone. You may fix the leak and fill back up... spending lot and then another occurs or that one opens up again. It's best to replace it with new coil and have a 10 year part warranty and full 1 year or more labor warranty. 😎

[@gwp1ohio]

@@97Napkins I got a professional to fix it, knock on aluminum.... Been a year so far so good.

[@97Napkins]

@@gwp1ohio congrats... hope all is well for this summer. #Change your filter. 😉

[@nunyabusiness6746]

500psi, do you have to suit up into bomb disposal gear ?

[@HVACRat]

How is this different than Hi-Alloy 129 or Super Alloy 5? Or is it just another product along the same vein?

[@brianphillips4115]

what flux are you using?

[@daviddelgado475]

This is called............skills.

[@dbzssj4678]

Is there a reason propane and butane are not used in HVAC? They burn hot enough.

[@gracida6]

butane is a bastard gas

[@frankmashione139]

Thanks for the demonstration

[@stevee7774]

I’m having nightmares of the tube collapsing as I heat it.... I swear it looked like that U tube almost started glowing. 😱

[@schmitty99]

Great video thank you!

[@Alex-yk6he]

Cool. I have been using a mapp gas because it burns cooler

[@johnnyprotalk3352]

What kind of flux?

[@DW-vl2wi]

What flux was used?

[@adamarcadegames]

It's a product also made by solder weld It turns clear at 600°, when you're ready to lay the rod it might come with the kit....

[@scooterbikeslead9005]

Great Video!

[@HVACS]

Glad you enjoyed it

[@jamminwrenches860]

Had a pinhole on the inside of a u-bend. I almost melted a big hole but saved it.

[@ebfsystem]

Can some one post a link where I can buy this rod please

[@DonBallew]

good stuffs. Great product, awesome company

[@donnierobertson3088]

Great job

[@Jack_The_Biker]

What nitrogen manifold is that?

[@HVACS]

Will be answering everybody's concerns in Q/A video

[@TheCajun337]

victor reinz

[@richardselby1711]

If you put that much heat on a micro-channel coil it will go away in an instant. The wall thickness isn’t thick enough on a micro-channel.

[@JuanTodoli]

Cool brazing.

[@palamidi13]

these are GOOD videos!!

[@frankevans588]

now that was a really good class

[@nathanielreid4967]

[@kiddsheppard]

kit part # ?

[@robertlyman9789]

They never show this stuff when they are in a 130 degree cramped attic space in the dark

[@youoweme5forreadingthisnam535]

Yeah. Just replace the evap at that point ffs

[@marknagy5892]

Just use JB weld so much cheaper .

[@LLLL666]

I would had used epoxy to fix the hole.

[@LLLL666]

@@nunyabusiness6746 Yea, I hope no-one took my advise. I'm not a HVAC at all!

[@maness2112]

Coil leaks suck.

[@vernonroach918]

Yea, but on a good day, so does my priest.

[@jewdali1]

PLEASE TRY TO SPEAK A BIT SLOWER SO PEOPLE WHOSE ENGLISH IS NOT THEIR MOTHER ENGLISH CAN FOLLOW YOU . THANK YOU FOR THE VIDS

[@HVACS]

Salvador Dali please try to make your art less impressionist and more literal. What do those melting clocks mean!!! 😉

[@mrcrux213]

Salvador Dali I can tell you that Brian talks very clearly and a slow speed you will be lost. Lol😎 Tomalo por el lado amable.

[@teddybhear3766]

Learn english and you wont have that problem. Why should he change the way he communicates because some people are to lazy or stupid to learn or understand English. So maybe non english speakers having a problem following what hes saying should learn to listen faster

[@fernandocisneros8113]

QUE DIJO?? NO ENTENDER NADA

[@daddygc871]

Why give such a smart ass answer

[@BdeJJG]

"rub out"

[@MrGarcon98]

nicely done ,,,,,even from a welders point of view LOL ,,,,,,alloys are a bitch they are picky lol

[@mrcrux213]

At this point will be to replaced the coil. Just kidding

[@stevee7774]

If I tried it you definitely would have to replace it.

[@hvacman77]

Yeah just replace the coil

[@HVACS]

Sometimes that’s the best option sometimes it isn’t.

[@channelcatchaser9426]

That's a big problem with the industry.....no one wants to fix anything just replace it

[@channelcatchaser9426]

@@scottgrinnell3909 I feel ya

[@tonyrichards2017]

@@channelcatchaser9426 it's not worth it lets say you send 3 to 4 hr repairing old coil $$$$$$ then it leaks in a new spot who pays for it you. No good deed goes unpunished new coil about the same time

[@channelcatchaser9426]

@@tonyrichards2017 i completely understand but on the other hand skill is lost if trade practices are not practiced.