I found the system low on refrigerant. I completed a complimentary refrigerant leak search on the system. I found the leak in the suction service valve. The customer signed for the repair. I ordered the part from the supply house. We will call and schedule a repair appointment when the part arrives. I recovered the refrigerant. I replaced the valve with the new one. I pressurized the system with 400psi nitrogen for 15 minutes. No leaks present. I placed the system under vacuum under 300 microns. I charged the system to manufacturer specifications. The system is working properly at this time.