Modes

4900 dm 05.02.002

Recirculation Mode

Warning: Do not use the recirculation mode when the heater is on and the vehicle is in motion. Driving with the recirculation mode on while the heater is on may cause the windows to be obscured by moisture or ice, which could result in an accident possibly causing personal injury or property damage.

Do not use the recirculation mode for more than 20 minutes at a time because the air inside the cab may become stuffy and the windows may become obscured by moisture, which could result in an accident possibly causing personal injury or property damage.

When the mode control switch (see Fig.) is turned to the face mode using recirculating air, the air in the cab is recirculated through the heater and air conditioner system. This is the only mode that uses recirculated air. Fresh air, or outside air, is circulated through the heating and air conditioning system when any other mode is selected.

  1. Face Mode (recirculating air)

  2. Face Mode (fresh air)

  3. Bi-Level Mode

  4. Floor Mode

  5. Floor and Defrost Mode

  6. Defrost Mode

Fig. 1, Mode Control Switch Settings

The recirculation mode can be used to prevent dusty or smoky air from entering the cab, or to decrease the time required to cool or heat the cab interior during extreme outside temperature conditions. When the outside air is clear or the desired cab temperature is reached, change the mode control switch to a fresh-air mode. The recirculation mode can be used when the air conditioner is on whether the vehicle is moving or not.

Defrost Mode

The defrost mode is used to deice, defrost, or defog the windows.

Note:  When the defrost mode is on, the air conditioner is on. The air conditioner is used to dehumidify the air entering the cab and to remove the moisture from the windshield.

Note:
Document Number: 0000121423
Manual Publication Date: 2024-06-10
Topic Publication Date: 2024-06-10