Repaired an old Trane air conditioner. Diagnosed a malfunctioning contactor using a multimeter. Removed the faulty contactor and replaced it with a new Trane OEM part. Inspected the condenser coils and cleaned them with coil cleaner. Verified refrigerant levels using a manifold gauge set and found them within the optimal range. Tested the system to ensure proper cooling performance and efficient operation. Conducted a final inspection to confirm all components were functioning correctly before leaving the site.