Refrigerant System Charge

Refer to "A/C Data Table" in the "A/C System Servicing" section for refrigerant capacities.

Fig. 4 A/C system charging (Typical):

CHARGING WITH 14 OUNCE CANS

Never use cans to charge into high pressure side of system (compressor discharge port) or into system at high temperature, as high system pressure transferred into charging can may cause it to explode.

1. Attach center hose from manifold gauge set to refrigerant dispensing manifold. Turn refrigerant manifold valves completely counterclockwise to open fully, and remove protective caps from refrigerant manifold.
2. Screw refrigerant cans into manifold, ensuring gasket is in place and in good condition. Torque can and manifold nuts to 6-8 ft. lbs.
3. Turn refrigerant manifold valves clockwise to puncture cans, and close manifold valves.
4. Loosen charging hose at gauge set manifold and turn a refrigerant valve counterclockwise to release refrigerant and purge air from charging hose. When refrigerant gas escapes from loose connection, retighten hose.
5. Fully open all refrigerant manifold valves being used and place refrigerant cans into pan of hot water at 125 °F. to aid transfer of refrigerant gas. Place water pan and refrigerant cans on scale and note weight. Do not heat refrigerant cans over 125 °F. as they may explode.
6. Connect jumper wire across terminals of cycling clutch switch connector located near "H" valve, if equipped, so that compressor clutch will remain engaged.
7. Start engine and set controls to A/C low blower position. Low pressure cut-out switch will prevent clutch from engaging until refrigerant is added to system. If clutch does engage, replace switch before continuing.
8. Charge through suction side of system by slowly opening suction manifold valve. Adjust valve so charging pressure does not exceed 50 psig.
9. Adjust engine speed to fast idle of 1400 RPM.
10. After specified refrigerant charge has entered system, close gauge set manifold valves, refrigerant manifold valves, and reconnect wiring.

CHARGING WITH BULK REFRIGERANT SUPPLY

Only a charging bottle may be used to charge liquid refrigerant through the compressor discharge muffler. Never charge with liquid through compressor inlet or suction line ports, as damage to compressor is likely to occur. Do not run compressor while adding liquid refrigerant.

1. Warm charging bottle in pan of 125 °F. water. Do not heat R-12 with a torch, as it may explode.
2. Loosen charging hose at gauge set manifold and slowly open refrigerant supply valve until refrigerant has purged air from hose. Retighten the hose.
3. Place refrigerant container upside down on scale and note weight.
4. Open refrigerant supply valve and compressor discharge gauge valve to charge system. When scale indicates proper amount of charge has entered system, close valves.

If required amount of refrigerant does not enter system, close compressor discharge valve on manifold gauge set. Turn charging bottle right side up so gas, not liquid, will enter system. Start engine and set A/C control in A/C position. Slowly open suction line valve on manifold gauge set. The compressor will draw refrigerant into system. Charging line valve should be set so suction pressure does not exceed 50 psig.