OPERATION IN EXTREME COLD.

TM 5-4120-384-14

OPERATION IN EXTREME COLD.

2-12.

wiring that

has b e e n

electrical

not

disturb

Both the wire

exposed to extremely low temperatures.

and i n s u l a t i o n b e c o m e b r i t t l e w h e n c o l d a n d a r e

easily broken.

The air conditioner is designed to operate in temperatures down to 50 F

(-45 C). E x t r a c a r e should be taken to minimize the heating load when

Some of the steps that may be

operating in extremely low temperatures.

taken are:

Check all openings in the enclosure, especially doors and windows,

to be sure they are tightly closed. Limit in and out traffic, if possible.

entry of direct rays of the sun,

Open shades and awnings to permit

if appropriate.

c . Limit the amount of cold, outside air

introduced

through

the

fresh

air damper to that needed for ventilation

NOTE

Weatherstripping, the installation of storm doors and

windows (if appropriate), and insulation of surfaces

e x p o s e d t o t h e o u t s i d e i s recommended when operation

at extremely low temperatures for extended periods is

anticipated.

Before attempting to start the unit in the COOL mode or when fresh

air is being used during the HEAT mode, be sure that cover is rolled up and

all exposed air openings are clear of ice and snow.

When the unit is to be used at low temperatures in the COOL mode,

the low refrigerant pressure cutout switch must be jumpered.

Contact

organizational maintenance. (See para 4-38.)

Be sure that all

dampers

are

operating

freely.

unit

not being used or is being used in the HEAT

mode

without fresh air,

close (roll down) and secure the fabric cover.

OPERATION IN DUSTY OR SANDY CONDITIONS.

2-13.

NOTE

Maintenance

Services

Prevent i v e

Checks

and

Unit

( P M C S ) should b e p e r f o r m e d a t

daily intervals.

can s e r i o u s l y reduce t h e

and s a n d y c o n d i t i o n s

Dusty

General.

mist

conditioner by clogging the air filter,

efficiency of the air

This will cause a restriction in the volume of

and coils.

eliminator,

Change 3

2-16