BI-LEVEL

The blower motor circuitry is turned ON. The fan speed knob adjusts the blower speed. The A/C compressor activates and runs in order to keep the evaporator core at about 1°C (33°F).

Vacuum is supplied to the defrost and A/C valve vacuum actuator.

The valves are in the following positions:
^ The air inlet valve is in the outside air position.
^ The defrost and A/C valve is in the A/C position.
^ The heater and A/C BI-LEVEL valve is in the bi-level position.

The blower pulls outside air into the system. The air is heated or cooled. The air is then forced through the instrument panel outlets.

The temperature control circuitry activates so that the temperature knob can adjust the discharge air temperature.