There are several formulas of A/C stop leak products on the market today. While some work very well, others can cause serious damage to an a/c system and refrigerant recovery machines. Leak stop products that you should be cautious of are any stop leak product that is a two-part or a two-step application and any product that reacts to moisture. All a/c systems contain a certain degree of moisture so introducing any products that reacts when moisture is detected or have hardening traits can cause irreversible damage to your a/c system, your service equipment and your tools. Aerosol leak stop products that contain dye and retail between $4.00- $7.00 work well for small o’ring leaks which usually take a few months to leak down.There are two leak stop products that WILL NOT harm any of your a/c system components or service equipment: Kwik Seal by FJC and Red Angel by Universal Products. Both Kwik Seal and Red Angel have proven to seal most leaks within 15 minutes. How do you determine if Kwik Seal or Red Angel will work on your leak? Your a/c system must hold 5” of vacuum for 25 minutes or 15” of vacuum for 5 minutes. If you don’t have a vacuum pump, this is equivalent to a system that leaks out in about 4 days. Kwik Seal and Red Angel work on all types of leaks: Condensers, evaporators, hose connections, gaskets, o’rings, valve cores and seals.
