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Charging A/C System

NOTE: Manufacturer does not recommend using one-pound cans. Using a charging station will allow precise measurement of refrigerant charge. See REFRIGERANT OIL & REFRIGERANT SPECIFICATIONS tables in the A/C COMPRESSOR SERVICING article for system capacities.
NOTE: DO NOT connect high-side gauge hose to high-side service port. Perform A/C charging service through low side only.
  1. System must be evacuated before charging. With manifold gauge set connected (from evacuation procedure), start engine, but DO NOT turn on A/C. Connect refrigerant drum to hose on center connector of manifold gauge set. Invert refrigerant drum for liquid charging. Open low-side gauge valve on manifold gauge set. Allow 16 ounces of refrigerant to enter system.
  2. When 16 ounces of refrigerant have entered system, turn A/C system to normal operating position with blower fan on high speed. Continue charging (liquid charging) until proper amount of refrigerant has entered system.
  3. Close refrigerant drum valve, and continue running A/C system for 30 seconds to clear lines and gauges. Turn off valve on manifold gauge set. With engine running, disconnect low-side hose, and install service valve cap at accumulator. Perform leak test procedure. See LEAK TESTING.
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