CHARGING THE REFRIGERATION SYSTEM (Continued)

TM 5-4120-359-14

After the system has been satisfactorily evacuated. it must be fully charged with Refrigerant-22.

CAUTION

Never introduce liquid refrigerant into the low pressure (suction) service valve.

NOTE

The system must be evacuated before charging. Use only Refrigerant-22 to charge

the unit. If available, use recycled refrigerant.

a. Check that the hose from the low pressure service valve is connected to the compound gage side of the charging

manifold. The hose from the high pressure service valve should be connected to the pressure gage side of the charging

manifold.

b. Connect the center hose from the charging manifold to a well charged drum of Refrigerant-22.

Loosen the hose connections to the two air conditioner service valves slightly.

d. Open the two charging manifold valves.

e. Open the Refrigerant-22 drum valve slightly to allow a small amount of refrigerant to purge air from the hoses.

Tighten the hose connections at the air conditioner service valves.

f. Close the low pressure (suction) charging manifold valve. Never introduce liquid refrigerant into the low pressure

(suction) service valve.

g. Position the Refrigerant-22 drum so that liquid will be used for charging. (Some drums must be inverted and

some are equipped with a selector valve.)

h. Using accurate scales, measure and record the weight of the Refrigerant-22 drum.

Open the Refrigerant-22 drum valve.

j. Open the high pressure service valve on the air conditioner. Allow liquid refrigerant to enter the system until the

drum weight has decreased by 6 pounds (2.93 Kg) or until system pressure has equalized.

Close the refrigerant drum valve and the high pressure (discharge) manifold valve.

Connect air conditioner to a remote control module assembly.

m. Connect power.

n. Turn air conditioner on and operate in the COOL mode with the TEMPERATURE CONTROL set at the maximum

COOLER position.

o. If the 6 pound (2.93 kg full charge was obtained, skip steps p through s. If the system pressure equalized prior to

obtaining a full charge of 6 pounds (2.93 kg) proceed with step p.

p. Switch the refrigerant drum to the gas only position.

q. Be sure that the refrigerant drum has been switched to the gas position and open the refrigeration drum valve, the

low (suction) pressure charging manifold valve and the low (suction) pressure service valve on the air conditioner.

r. Monitor the weight of the refrigerant drum as the air conditioner compressor pulls additional refrigerant gas into

the system until the full 6 pound (2.93 kg) charge is obtained. When the system is fully charged, immediately close the

refrigerant drum valve and the air conditioner low pressure service valve.

4-34 Change 4