Your Vehicle: 2001 Ford Escort ZX2 L4-2.0L DOHC VIN 3
 
Vehicle » Heating and Air Conditioning » Description and Operation » General Information » System Operation  
 
 
  System Operation  
 

  

MAX A/C
When MAX A/C is selected:

  • The air inlet duct door is at full vacuum, closing off outside air and admitting only recirculated air.
  • The panel vent airflow door and the defrost/floor airflow door are at full vacuum, directing airflow to the A/C registers.
  • Temperature control is usually set for maximum cold but may be heated if selected.
  • Air will be picked up at the recirc opening by the blower motor. With the temperature control set for maximum cold, airflow across the A/C evaporator core will be diverted past the heater core and then directed into the passenger compartment through the instrument panel A/C registers.
  • The A/C compressor will be enabled when MAX A/C is selected.
  • The blower motor is on.

  

A/C
When A/C is selected:

  • The air inlet duct door is set at no vacuum, blocking the recirc passage and admitting outside air.
  • All other door positions are the same as described under MAX A/C.
  • Temperature setting can be changed manually.
  • The A/C compressor will be enabled when A/C is selected.
  • The blower motor is on.

  

PANEL
When VENT is selected:

  • The air inlet duct door, with no vacuum being applied, will block recirculated air and admit outside air. From there, air flows through the system to the instrument panel A/C registers.
  • The panel vent airflow door is at full vacuum to block airflow to the heater assembly floor ducts.
  • The defrost/floor airflow door is at full vacuum, closing off airflow to the windshield defroster hose nozzles.
  • The temperature setting can be changed manually to heat the air but air cannot be cooled below the outside temperature.
  • The A/C compressor will be disabled when VENT is selected.
  • The blower motor is on.

  

OFF
When OFF is selected:

  • The A/C inlet duct door is at full vacuum, closing off outside air and admitting only recirc air.
  • The panel vent airflow door is at no vacuum and the defrost/floor airflow is at full vacuum, closing off the passages to the A/C registers.
  • The blower motor and the A/C compressor are off.

  

PANEL/FLOOR
When PANEL/FLOOR is selected:

  • The air inlet duct door is set at no vacuum, blocking the recirc passage and admitting outside air.
  • The heater panel vent airflow door is in the partial vacuum position, allowing airflow to both the A/C registers and the heater assembly floor ducts.
  • The defrost/floor airflow door is at full vacuum, closing off airflow to the windshield defroster hose nozzle and directing airflow to the heater outlet floor duct.
  • The A/C compressor will be enabled when PANEL/FLOOR is selected.
  • The blower motor is on.

  

FLOOR
When FLOOR is selected:

  • The air inlet duct door is in the no vacuum position, blocking recirc air and admitting outside air.
  • The defrost/floor airflow door is in the vacuum position, closing off airflow to the windshield defroster hose nozzles.
  • The temperature control can be positioned to mix air flowing through and around the heater core to achieve the selected temperature level.
  • The panel vent airflow door is in the no vacuum position, blocking air circulation to the panel A/C registers.
  • The A/C compressor will be disabled when FLOOR is selected.
  • The blower motor is on.

  

FLOOR/DEFROST
When FLOOR/DEFROST is selected:

  • The air inlet duet door is in the no vacuum position blocking recirc air and admitting outside air.
  • The defrost/floor airflow door is in the partial vacuum position, allowing airflow to both the windshield defroster hose nozzle and the heater assembly floor ducts.
  • The panel vent airflow door is in the no vacuum position.
  • The A/C compressor will be enabled when FLOOR/DEFROST is selected to dehumidify the air and reduce windshield fogging.
  • The blower motor is on.

  

DEFROST
When DEFROST is selected:

  • The air inlet duct door is in the no vacuum position, admitting outside air.
  • Both the panel vent airflow door and the defrost/floor airflow door are in the no vacuum position so that most of the incoming air is directed to the windshield defroster hose nozzle. There is also airflow to the side window demister and hose.
  • The temperature control knob setting will determine the amount of air that is directed through the heater core and the amount that bypasses the heater core.
  • The A/C compressor will be enabled when DEFROST is selected to dehumidify the air and reduce windshield fogging.
  • The blower motor is on.