One of the weak points in such a long running unit is the run capacitor. If the compressor fails to run (kick in), the run cap is a good suspect. It's the 2" x 4" cylinder inside the unit near the middle top. The value is: 30 + 7.5 MFD 370 Volt, available here: http://www.carbonbrush.com/runcapacitorsround370.htm . The fan wire(s) connect to the terminal marked "FAN" or "F" (Sometimes GREEN), compressor to "HERN" or "H" (Sometimes WHITE), commons to "C" (Sometimes BLACK). God's Blessings in your endeavor.