Last year at the yearly maintenance for my ac unit they discovered that my unit was leaking refrigerant. They added stop leak and added the refrigerant that had leaked, they did warn me that the work performed did not guarantee that my unit would not leak but they would reimburse me for half of the cost so I went ahead and had the work done. My unit worked for the rest of the season but this year when they came out again is was leaking. I decided it was time to purchase a new unit. Everything was great and as always the men are always working and cheerful and nice. I think Ill be happy with the new quieter unit.