TM 9-4120-371-14
An overheat thermostat located near the heating elements will turn them off if the
temperature in the heater compartment reaches an excessive level.
In the HI HEAT mode, six heaters are activated. Three are thermostatically controlled. Three operate all of the
time.
a. Turn mode selector switch to HI HEAT.
b. Turn Temperature control thermostat knob as far as it will go in the INCREASE (warmer) position.
c. When room or enclosure temperature reaches the desired level, slowly turn the Temperature control
thermostat knob toward DECREASE. Make small adjustments until desired temperature is maintained
automatically.
NOTE
Should unit continue to produce too much heat with Temperature control thermostat
knob adjusted toward the decrease setting, switch to LO HEAT
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.
