Diag/ system not cooling properly, freezing up. Arrived and found system is a bit low on r22 refrigerant. Added 2 lb r22 to get system cooling properly, pressures now at 70/220 with 9° superheat and 20° temperature split across evaporator coil. Due to age (1996) and condition of the system I highly recommend replacing the existing equipment. Sent proposal to customer’s email at this time.