TM 9-2320-360-10
2-15.1. VENTILATOR OPERATION
(1) Set blower fan switch (1) high (H), medium (M), or low (L) speed.
(2) Turn recirculate/fresh air knob (2) counter-clockwise to unlock.
NOTE
Recirculate fresh air control knob should remain in recirculate
position when operating HET tractor in dusty conditions.
(3) Pull control knob (2) out to add fresh outside air into cab.
(4) Push control knob (2) in to recirculate air inside cab.
(5) Turn recirculate/fresh air knob (2) clockwise to lock in position.
(6) Adjust air flow rate and direction with louvers (3) and (4).
(7) Turn blower fan switch (1) to OFF position when ventilator operation is not desired.
Change 1 2-146.1