Refrigerant Drum Method

Charging the System:

REFRIGERANT DRUM METHOD

A. The evacuation procedure will specify 711-737 mm (28- to 29-inches) of mercury at sea level. For each 304.8 mm (1,000 ft.) above sea level, lower the specifications 25.4 mm (one inch) of vacuum. At 1,524 mm (5,000 feet) of elevation only 584.2-609.6 mm (23- to 24-inches) of mercury (vacuum) is required.

B. If the prescribed (vacuum) cannot be reached, close the vacuum control valve, shut off the pump and look for a leak at the connections or the pump.

3. When the gage reaches the prescribed vacuum, the system is evacuated. Close the high side gage set valve and turn OFF the vacuum pump.

4. Watch the low side gage to be sure vacuum holds for five minutes. If the vacuum holds disconnect the vacuum hose at the gage set and then proceed to charging.

5. If the vacuum does not hold for five minutes, charge the system with 0.227 kg (8 oz.) Refrigerant-12 and leak check. Discharge the system again and repair any leaks. Repeat the evacuation procedure.