Section III. Operation Under Usual Conditions

TM 5-4120-364-13

Section III. Operation Under Usual Conditions

2-3.

GENERAL.

a . T h e instructions in this section are for the information and guidance of

personnel responsible for the operation of the air conditioner.

b . The operator must know how to perform every operation of which the air

c o n d i t i o n e r is capable. This section gives instructions on starting and stopping the

air conditioner, basic motions of the air conditioner, and on coordinating basic

m o t i o n s to perform specific tasks for which the equipment is designed.

c . Although the air conditioner is normally used for mechanically cooling

t h e control space automatically, it may also be used to ventilate only. Care should

b e taken to insure that doors to the conditioned space close with a good seal against

t h e ambient (outside) air. frequent door opening will impose an abnormal load on the

a i r c o n d i t i o n i n g uni t , p r e v e n t i n g no r m a l on an d o f f cy c l e s .

d . The operator must be observant at all times, particularly concerning un-

u s u a l sounds that would indicate malfunctioning of the air conditioner. When unusual

s o u n d s occur, stop operation and report to organizational maintenance.

2-4.

OPERATION.

Starting.

( 1 ) R e f e r t o paragraph 2-2 and perform the daily preventive maintenance

c h e c k s and services.

(2) Refer to figure 2-1 and start the air conditioner.

( 3 ) The coolest setting of the thermostat should correspond to a temp-

erature of approximately 60F (18C) in the conditioned air space. After several

h o u r s of operation at this setting, the thermostat may be set back from the extreme

c o o l i n g position to attain whatever temperature above 60F (18C) is desired in the

conditioned air space.

( 4 ) For operation when the unit is equipped with an external thermostat,

turn the selector switch to "EXTERNAL CONTROL" and the temperature will be controll-

e d by the setting of the external thermostate.

( 5 ) F o r v e n t i l a t i o n o n l y , t u r n t h e s e l e c t o r switch to "VENTILATION". In

this mode, only the evaporator fans will operate.

R e f e r to figure 2-1 and turn the s e l e c t o r switch to "OFF".

Stopping.

Section IV. Operation Under Unusual C o n d i t i o n s

2-5.

OPERATION IN EXTREME COLD.

a. The air conditioner is designed to operate on the ceding cycle without

f o r m i n g frost or ice on the evaporator coil at an ambient ( o u t s i d e ) t e m p e r a t u r e a s

l o w as 60F (18C).

2-3