Auxiliary Climate Control

An optional auxiliary air conditioning and heating system is available on the Windstar vehicles. The system is a one-piece unit that is located on the left hand side of the vehicle between the side windows and the floorpan, behind the rear wheel well. The auxiliary air conditioning and heating system is also equipped with an auxiliary control, mounted over the right sliding door.

All of the auxiliary A/C-heater system components are accessed from the inside of the vehicle.

Air Distribution
The vehicle has a vertical duct that supplies air to the integral headliner air conditioning duct. Air is supplied to the passengers through four adjustable registers. The heater floor duct is located on the left side in front of the left rear wheel well and directs airflow through the floor register into the passenger compartment.

System Airflow
The Auxiliary Climate Control feature provides a rear climate control system with a multi-speed blower, temperature blend, and three modes: floor, overhead and a split between the two. The system can be controlled by the driver using the main climate control head or by the rear passengers using the auxiliary climate control when the front control is set to give the rear control command.

^ The A/C-heater temperature blend and mode is controlled by the rear auxiliary temperature control head so that when the auxiliary control head is in the warm temperature range, the airflow is at full floor and when the auxiliary control head is in the cool temperature range, the airflow is at full overhead and when the aux control head is in a mid temperature range, the airflow is split between the floor and overhead.
^ When the main climate control assembly is in any position except OFF and the rear blower switch is in any position except REAR CTL, the front climate control head has control over both Systems.
^ The front A/C temperature control operates in the same fashion as the rear temperature control. When the temperature is at full heat the airflow is at full floor. When the temperature is at full cool the airflow is at full overhead, and when the temperature is in the mid-range the airflow is split between the floor and overhead.

Blower Motor
The auxiliary air conditioning and heating assembly contains a blower motor. It is controlled by the heater blower motor switch on the front or rear auxiliary A/C control.

Control Assembly
The auxiliary A/C-heater system has a climate control assembly, mounted in the headliner in the rear of the vehicle over the right sliding door. This control assembly has the same settings as the A/C-heater blower switches located on the main A/C control. These switches allow the auxiliary blower motor to be operated independently of the main blower motor. By placing the main heater blower motor switch in the REAR CTL position, the auxiliary blower motor can then be controlled from the rear climate control panel.

Heater Core
The auxiliary A/C system uses a rear-mounted heater core which operates in the same manner as the front-mounted heater core.

A/C Evaporator Core
The auxiliary A/C system uses a rear-mounted A/C evaporator core which operates in the same manner as the front-mounted A/C evaporator core.







Thermostatic Expansion Valve
An A/C evaporator expansion valve regulates the flow of refrigerant into the auxiliary A/C evaporator core. It is also the dividing point in the system between low- and high-pressure sides.

The temperature sensing bulb measures the temperature of the refrigerant in the suction line and transmits it to the A/C evaporator expansion valve. This temperature variation regulates the refrigerant flow to the auxiliary A/C evaporator core.

^ When the bulb senses a high temperature, the A/C evaporator expansion valve opens and provides refrigerant through the auxiliary A/C evaporator core.
^ When the bulb senses a low temperature, the A/C evaporator expansion valve starts closing to shut off the refrigerant to the auxiliary A/C evaporator core.