TM 9-4120-407-14
SECTION IV OPERATION UNDER UNUSUAL CONDITIONS
2-10. GENERAL. The Model F36T-MPI Air Conditioner is designed to operate normally within a wide
range of climatic conditions. However, some extreme conditions require special operating and servicing
procedures to prevent overloading and excessive wear on the equipment.
2-11. OPERATION IN INCLEMENT WEATHER.
a . Operation In Extreme Heat. The air conditioner is designed to operate in temperatures up to 120 F
(49 C). Extra care should be taken to minimize the cooling load when operating in extremely high
temperatures. Some of the steps that may be taken are:
(1) Check all openings in the enclosure, especially doors and windows, to be sure they are tightly
closed. Limit in and out traffic, if possible.
(2) When appropriate, use shades or awnings to shut out direct rays of the sun.
(3) When possible, limit the use of electric lights and other heat producing equipment.
(4) Limit the amount of hot, outside air introduced through the fresh air damper to that essential for
ventilation.
(5) Clean filter, mist eliminator, and coils more frequently.
Do not disturb electrical wiring that has been exposed to extremely
low temperatures. Both the wire and insulation become brittle when
cold and are easily broken.
b. Operation In Extreme Cold. The air conditioner is designed to operate in the HEAT mode at
temperatures down to -50 F (-45 C) and in the COOL mode at outside temperatures down to 45 F (7 C).
Extra care should be taken to minimize the heating load when operating in extremely low temperatures.
Some of the steps that may be taken are:
(1) Check all openings in the enclosure, especially doors and windows, to be sure they are tightly
closed. Limit in and out traffic, if possible.
(2) Open shades and awnings to permit entry of direct rays of the sun, if appropriate.
(3) Limit the amount of cold, outside air introduced through the fresh air damper to that essential for
ventilation.
NOTE
Weather stripping, the installation of storm doors, and windows, if
appropriate, and insulation of surfaces exposed to the outside is
recommended when operation at extremely low temperatures for
extended periods is anticipated.
(a) Before attempting to start the air conditioner in the COOL mode or when fresh air is being
used during the HEAT mode, be sure that fabric cover is rolled up and all exposed air openings
are clear of ice and snow. Be sure that fresh air damper (door) is operating freely.
(b) If air conditioner is not being used or is being used in the HEAT mode without fresh air, close
(roll down) and secure the fabric cover.
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