2011 Chevrolet Express 1500 Cargo Owner's Manual - Page 214

8-8 Climate Controls Be sure to keep the area under the front seats clear of any objects so that the air inside of the vehicle can circulate effectively. For information on how to use the main climate control system, see Climate Control Systems on page 8‑1. For information on ventilation, see Air Vents on page 8‑8. Air Delivery Mode Control: Turn clockwise or counterclockwise to change the direction of the airflow in the rear seating area. To change the current mode, select one of the following: Air Vents Use the outlets located near the center and on the sides of the instrument panel to change the direction of airflow. H (Vent): Air is directed to the upper outlets, with some directed to the floor outlets. 2 (Floor): Air is directed to the floor outlets. Operation Tips . Clear away any ice, snow or leaves from the air inlets at the base of the windshield that may block the flow of air into the vehicle. Use of non-GM approved hood deflectors may adversely affect the performance of the system. Keep the path under the front seats clear of objects to help circulate the air inside of the vehicle more effectively. . .