TM 9-4120-404-14
2-8. OPERATION IN VENT MODE. (No Heating or Cooling Needed).
NOTE
The fabric cover must be rolled up and secured if fresh air damper (door) is to be
opened. When using fresh air for ventilation, a window, door, or vent should be
opened. If the room or enclosure is tightly closed, an over pressure will build up
and decrease the volume of fresh air drawn in.
a. Turn mode selector switch to VENT.
b. Adjust fresh air damper to desired setting. The unit can be operated in the VENT mode with the fresh air damper
(door) closed, open, or partially open.
c. Adjust louvers to suit.
NOTE
To pull in maximum of fresh (outside) air, close conditioned air inlet louvers.
2-9. OPERATION IN HEAT MODE. In the HEAT mode six thermostatically controlled heaters are activated. To operate
the unit in HEAT mode perform the following steps.
a. Turn mode selector switch to HEAT.
b. Turn temperature control thermostat knob as far as it will go in the WARM position.
c. When room or enclosure temperature reaches the desired level, slowly turn the temperature control thermostat
knob toward COOL. Heating will stop when you reach the approximate room temperature. Further adjustment can be
made by turning the temperature control thermostat knob slightly toward WARM or COOL until desired temperature is
controlled automatically.
NOTE
An overheat thermostat located near the heating elements will turn them off if the
temperature in the heater compartment reaches an excessive level.
NOTE
Fresh (outside) air cannot be introduced with fabric cover down. Close damper.
d. Adjust fresh air damper (door) to desired setting. It is normally better to keep the fresh air damper slightly open.
Damper should be closed during very cold weather and during fast warmup periods.
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