Charging the A/C System

Charging A/C System:

Charging the Air Conditioner System

1. Start engine. Run until normal operating temperature is reached; keep A/C "OFF."
2. Place drum of Refrigerant-12 upside-down on a weight scale.
3. Connect center hose of manifold gage to R-12 drum nozzle (having reconnected Schrader valve tip from oil procedure).
4. Open valve on the R-12 drum and the low-side manifold gage.
5. Allow one half (0.5 lb., 1200 g) pound of refrigerant to flow into A/C system, then shut off manifold valve. The amount of refrigerant entering the system can be monitored by watching the weight of the canister-when it has decreased by one half pound, then one half pound of refrigerant has been added to the A/C system.
6. Switch A/C controls to "NORMAL" and the blower fan to "HIGH."
7. Re-open manifold valve and fully charge A/C system.

Specified Amount of Refrigerant-12:
600 to 750 b (1.3 to 1.7 lbs.).

To speed the charging process up, a large capacity fan can be used to pass air over the condenser. The R-12 will enter the system faster if condenser temperature is kept low.

8. Turn off the R-12 source valve. Run engine for 30 seconds to clear lines and gages.
9. With engine running, remove the manifold charging hoses (low-side first). Hold down valve and unscrew rapidly to avoid loss of R-12.

CAUTION: Never remove a gage line from its adapter when the line is connected to the A/C system. To disconnect a line, always remove the line adapter from the service fitting. Do not remove a charging hose from the gage set while the hose is attached to the low-side service fitting. Doing so will cause the system to discharge completely because the Schrader-type valve on the fitting is depressed. This discharge may cause personal injury due to escaping Refrigerant-12.

10. Replace protective caps on line fittings.
11. Turn off engine.
12. Check for leaks using electronic leak detector J 29547.