1.3 Ventilation, Heating, and Air Conditioning

Ventilation is by a flow-through system. Fresh air enters the car at the air intake in the right side of the plenum chamber in the body cowl. Interior air exits through vents located in the side trim panels of the luggage compartment. A three-speed fresh air blower assists air flow.

A blend heating system is used for faster reaction and less fluctuation in passenger compartment temperature levels. In a blend system, coolant always flows through the heater core. Temperature is regulated by a blending door which controls the amount of air that passes through the heater core before it enters the passenger compartment. Two other doors control the flow of air to the windshield and the passenger compartment. See Fig. 1-1.

Cars with air conditioning also use a blend system. Fresh air is first cooled and dehumidified by the evaporator. A portion of the air can then be directed by the blending door through the heater core to maintain the desired temperature. In very hot conditions the interior air can be recirculated for maximum cooling.