INDICATORS. - TM-5-4120-384-140039

TM5-4120-384-14

2-3.

INDICATORS.

(See

fig.

The refrigerant sight glass is the only visual indicator

incorporated in the air conditioner.

The refrigerant sight glass

has a small chamber with a glass window through which the

refrigerant condition can be observed.

It is installed in the

liquid refrigerant line downstream from the condenser coil.

Liquid

refrigerant actually flows through the sight glass chamber only

during cooling cycles when the air conditioner is in operation in

The unit must be operated approximately 15 minutes

the COOL mode.

at maximum cooling prior to checking condition of refrigerant at

sight glass.

The sight glass is equipped with a center indicator

that is moisture sensitive. Dry refrigerant is indicated by the color green, which changes

to chartreuse when the moisture content becomes undesirable, and to yellow when the

level becomes unacceptable. Excessive moisture in the refrigerant may damage or possibly

destroy the compressor. If the liquid refrigerant observed in the sight glass has a milky

appearance, or if frequent bubbles appear, the volume of refrigerant is low and the system

should be charged. Moisture or low charge indications should be reported to direct support

maintenance for appropriate refrigeration system action.

Do not operate the air conditioner in the COOL mode

if the refrigerant color has reached the yellow band

or if numerous bubbles appear in the sight glass.

COOL mode operation may be continued with the

refrigerant color in the chartreuse band or with only

an occasional bubble appearing in the window, but the

sight glass should be rechecked after each four hours

of operation to insure that the condition has not become worse. Damage to

the equipment may result if Personnel fail to observe precautions.

Change 1

2-5