During my last visit I discovered the system had no freon in the system at all. After searching the system for a leak I could not find one in the condensor or evap coil. Are search indicates the leak is in the line set. This was more then likely due to the roofers puncturing the line with a nail. This is a very common and is something I see all the time. Cheryl told me that the system was working fine up to the point where the roofers had compelted there work. At which point she called us because the system was down.