AC clean and tune. Used refrigerant sniffer to test indoor coil for possible refrigerant leaks, found none. Cycled system. Checked and cleaned electrical compartment. Found contactor worn. Tested compressor, came back in the normal range, but it is getting weak. Used coil cleaner on condenser coil. Hooked up gauges and tested pressures and temperatures. Found system slightly low on R- 22 refrigerant. Indoor coil temperature is 42, sub cooling is 23, temp split is 19. Average life of this unit is 14 years, this system is 24+ years old and showing signs of ware, due to age, efficiency, and cost to repair, second opinion is recommended. Future failure is expected. Job complete.