You should have four slides (two blue and two red). The top left blue lever directs air to the windshield. The lever toward the side of the car is open and toward the center of the car is closed. The top right blue lever directs air to the drive and rear floor area. Again, center - closed, side - open. The two red levers control heat on the left side (left) and right side (right). Levers to the sides - warm, and to the center - cold. the blue levers control the volume of air and both should be open for heating.

You also have a three speed blower switch. Obviously, turn it clockwise to adjust the blower.

Remember that if you have fresh air vents above the sliding levers, opening that simply allows fresh air to come in from outside.

Lastly, make sure that your air conditioner is completely turned off and you are not using that as another blower control.

Hope that helps.

Bill