Performed routine AC maintenance on a Carrier Performance 16 unit. Began by cleaning the condenser coils to remove any dirt and debris that could impede airflow. Checked the refrigerant levels and adjusted them to the manufacturer's specifications. Inspected the electrical connections and tightened any loose wires. Lubricated the fan motor and ensured the thermostat was calibrated correctly. After completing the maintenance, tested the system to confirm efficient operation and optimal cooling performance. The unit is now running smoothly.