How to Fix a Leak in an Aluminum Coil

Aluminum coils provide heat transfer for home heating and cooling systems. When an aluminum coil has a leak, your heating or cooling system won't work as well. You may notice that your air conditioning stays on but the house doesn't cool off. By using an epoxy sealant, you can quickly repair the leak. Look for an epoxy sealant that is NSF approved if you're fixing a leak on a potable water line, and seek professional help if the hole is larger than 1/8 inch.

Locating and fixing an aluminum coil can save you money.

Step 1

Locate the leak. If the aluminum coil has a visible puncture in it, you won't have to use a leak detector, but if you don't see any visible damage to the aluminum coil, use an infrared leak detector. Turn the leak detector on, and run it along the aluminum coils. The leak detector's infrared sensors pick up leaking refrigerant because the refrigerant makes a cloud around the leak that is invisible to your eyes but is like a shadow to the leak detector. It will beep rapidly when it encounters the cloud of refrigerant.

Step 2

Vacuum around the leak to remove any refrigerant that has leaked out of the aluminum coil. Use a knife or stainless steel brush to mechanically clean the area around the leak. When cleaning the area, avoid using any products that leave a residue behind because the epoxy will adhere to the remaining residue instead of the aluminum.

Step 3

Use a flame torch to heat the area adjacent to the leak. Test the sealing epoxy by touching it to the heated aluminum, but do not touch the epoxy directly to the flame or it will melt.

Step 4

Rub the sealing epoxy on the leak in the aluminum coil as soon as the epoxy begins to melt. Rub the melting epoxy thoroughly all over and around the hole.

Step 5

Put a cool wet rag on the repair to cool it quickly and to solidify the epoxy. Test the aluminum coil with the leak detector one more time to ensure that the leak is completely fixed.

Step 6

Cut off the cured end of the epoxy stick with a knife before you use it next time. You can't reuse cured epoxy.