RAM 2013 CHASSIS CAB 3500 Owner's Manual page 247

Bi-Level Mode
Air is directed through the panel and floor outlets.
NOTE: There is a difference in temperature (in
any conditions other than full cold or full hot), between
the upper and lower outlets for added comfort. The
warmer air goes to the floor outlets. This feature gives
improved comfort during sunny but cool conditions.
Floor Mode
Air is directed through the floor outlets with a
small amount through the defrost and side win-
dow demist outlets.
UNDERSTANDING YOUR INSTRUMENT PANEL 245
Mix Mode
Air is directed through the floor, defrost and side
window demist outlets. This setting works best in
cold or snowy conditions that require extra heat at
the windshield. This setting is good for maintaining
comfort, while reducing moisture on the windshield.
Defrost Mode
Air is directed through the windshield and side
window demist outlets. Use the DEFROST mode
with maximum blower and warm temperature settings
for best windshield and side window defrosting.
NOTE: The air conditioning compressor operates in MIX
and DEFROST, or a blend of these modes even if the A/C
button is not pressed. This dehumidifies the air to help
dry the windshield. To improve fuel economy, use these
modes only when necessary.
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