Repair Aluminum Air Conditioning and Radiators with Super Alloy 5

How to Repair an Aluminum Air Conditioning Return Loop with Super Alloy 5 Aluminum Rod and Flux Repair Kit

Today we are going to repair an aluminum air conditioning return loop.   If you need to repair aluminum air conditioner lines–be it for the home, car, heavy machinery, marine etc., Super Alloy 5 is the go-to brazing rod for thousands of US air conditioning shops.

To demonstrate the repair technique, we poked a hole in an air conditioning return loop to show how quick and easy this permanent repair can be.

Using a propane torch with a trigger start tip, we broadly heat the return loop to bring it to proper working temperature. 

Next, apply the heat to the end of the rod and dip it into the flux to adhere the flux to the rod.  If the flux does not adhere to the rod, just re-heat the rod and repeat.  Notice we preheat the tube for a few seconds prior to brazing.

Finally, melt the flux with the torch and apply it to the tube. Allow the flux to clean and prime the aluminum and then melt the rod while continuing to heat the aluminum.

This is a metal to metal repair; 30,000 psi. Stronger than any plastic or epoxy; and this is a permanent repair.

Our unique flux is essential for sealing the air conditioner and, of course, it was also able to remove years of contaminants–oil, grease and dirt.

Now that is a perfect repair.

You don’t know how many times I’ve heard, “Where were they before I bought this expensive MIG or TIG machine that I don’t know how to use? And you even did better with a hand torch! “



  • While it is not necessary to pre-clean the aluminum before making the repair, a clean part will  decrease the amount of flux needed.
  • Notice the technique: As soon as the rod began to flow, the heat is removed very quickly to avoid overheating the base metal.
  • Turn down the oxygen when working on thin aluminum parts.


NotePlease observe all AWS Safety & Health Guidelines when using Muggy Weld products.