One system a/c repair and tune up complete. Changed filter. Found water in drain pan caused by improperly constructed drain line. Did a quick reconstruction for drain line to drain properly. Found evaporator coil to be rusty and corroded. Did a leak search and found a leak in the evaporator coil. Refrigerant pressures are okay at this time but evaporator coil is actively leaking. There is no water safety on system to shut it off as a safety in the event of water in the drain pan. Voltage absorption system is running weak. Due to age and condition of system, recommend upgrading system to a more reliable, more efficient system. System is cooling at this time. Added leak sealer to system (not guaranteed) and replaced voltage absorption system