SERVICING REFRIGERANT SYSTEM. (cont)

TM 5-4120-369-14

6-3.

SERVICING REFRIGERANT SYSTEM -Continued.

(5) Charging the System - Continued.

NOTE

Whenever available, use recycled refrigerant for charging the

refrigeration system.

Remove service valve access cover. Remove valve caps and loosely connect charging manifold

Step 1.

service lines to air conditioner charging valves. Attach line from refrigerant drum to manifold.

Step 2.

Open refrigerant drum valve and manifold valves and purge air both from manifold and service

lines. Tighten service line connections at charging valves and close low side valve on charging

manifold.

Step 3.

Position refrigerant drum upside down on a scale. Open air conditioner high pressure charging

valve and charge system until scale indicates a full charge, then close both high pressure charg-

ing valve and drum valve. Disconnect charging lines unless, due to pressure qualization in drum

and air conditioner system, a full charge is not measured, then proceed to step 4.

Step 4.

Position refrigerant drum upright on scale with lines connected for gas charging. If the weight or

refrigerant to fully charge the system is known, operate air conditioner with controls set for

maximum cooling. Open refrigerant drum valve, low pressure charging valve, and low side

manifold valve. Continue operation until the system is fully charged, then close valves. Stop air

conditioner operation and disconnect charging lines.

To add refrigerant to system with low charge as indicated by bubbles in liquid sight indicator:

Step 5.

with refrigerant drum upright, connect lines for gas charging through low side manifold valve.

Purge charging lines by loosely connecting line at drum valve and slightly opening air condi-

tioner charging valves. Tighten line at drum valve. Operate air conditioner with controls set for

maximum cooling. Open refrigerant drum valve, low side manifold valve, and low pressure

charging valve on air conditioner. Continue operation until bubbles no longer appear in sight

indicator. Then close low pressure charging valve on air conditioner. Repeat charging if bubbles

reappear in sight indicator. When bubbles do not reappear after 15 minutes of operation, the

system is fully charged. Close charging valves and disconnect lines.

6-4.

REPAIRING REFRIGERANT LEAKS.

Locate leak (paragraph 5-6).

Discharge system (paragraph 6-3), repair leak, and recharge system (paragraph 6-3).

NOTE

If soldering is necessary on any part of the system, a constant

purge of dry nitrogen must be fed through the system being sol-

dered to prevent scale formation within the system.

6-5.

DECONTAMINATION.

General. The compressor is a hermetically sealed unit and cannot be repaired. An inoperative compressor is

usually due to a mechanical failure or motor burnout. If the compressor is mechanically frozen or sustains a motor burnout, it

must be replaced. A compressor failure generates high temperature causing a breakdown of oil, refrigerant and motor

insulation. with the resulting formation of acid, moisture, and sludge. These products are extremely corrosive and must be

flushed from the system or repeated burnouts will occur.

Change 2

6-5