Fig. 12.1. Schematic diagram of air flow in the ventilation, heating and air conditioning system: 1 – windshield blower deflectors; 2 – air flow distribution flaps to the windshield deflectors and instrument panel deflectors; 3 – instrument panel deflectors; 4 – air ducts for heating the driver"s and passengers" footwells; 5 – air flow distribution flap to the instrument panel deflectors and heating air ducts for the driver and passenger footwells; 6 – heater radiator; 7 – cabin air filter; 8 – air recirculation system damper; 9 – air intake box; 10 – air intake in the car interior; 11 – fan impeller; 12 – fan electric motor; 13 – air conditioner evaporator; 14 - drainage hole for condensate drainage; 15 – temperature regulator flap; 16 – heating and air conditioning system unit housing
The car is equipped with a liquid type heater.
The heater radiator is connected to the engine cooling system by two hoses running in the engine compartment. The radiator is placed in a plastic casing of the climate control unit, installed under the central part of the instrument panel.
Main components of the heater (Fig. 12.1):
– heat exchanger (radiator) 6 of the heater, designed to heat the air entering the passenger compartment with the heat of the engine cooling liquid;
– fan (air blower) 11. Electric motor 12 of the fan with excitation from permanent magnets, providing regulated supply of outside air to the heater and air conditioner flaps.
To obtain different values of the rotation speed of fan B, an electronic control unit A is installed in the power supply circuit of the electric motor; – valve 15 of the air temperature regulator entering the passenger compartment from the heater.
The amount of air passing through the heater heat exchanger and outside air bypassing the heat exchanger depends on the change in its position; – flaps 2 for distributing air coming from the heater through air ducts into the passenger compartment or for blowing the windshield.
The heat exchanger (radiator) can be accessed from the right side of the climate control unit. The heat exchanger can be removed and installed without removing the climate control unit housing.
When removing a factory-installed heat exchanger, the coolant supply lines must be sawed through. When replacing, a heat exchanger with separate, removable coolant supply lines is installed.