Pulling Vacuum
- Close all Valves and Connect Hi/Lo Gauges
- Connect Yellow Line to Vacuum Pump and Turn On
- Open Both Hi/Low Valves and Both Should Go Near -30 inches of mercury
- Vacuum Down System for 30 minutes
- Turn off Vacuum Pump and wait 30 minutes to 1 hour
- Verify that gauges are still showing near -30 inches of mercury
- If not, check for leaks. If so, run vacuum pump for 45m to 1hr longer
- Close both Hi/Lo valves, turn off pump, and disconnect yellow line
Adding Freon
- Connect adapter to 134a freon can
- If needed, add dye and oil to yellow line
- Connect yellow line to freon can and pierce the can and open the valve
- Purge yellow line until freon comes out
- Start the car, turn AC on, and turn fan to low
- Open only the LOW side valve. Low side pressure should increase to 50+ psi
- Listen for the compressor to engage. If it does, the pressure should immediately drop to around 10psi and the high side pressure should increase
- Shake can periodically and notice if refrigerant is still moving through watch glass. Wait until can is empty.
- Close the LOW side valve completely and close the refrigerant adapter valve
- Add the second can, pierce it, and open the valve
- Purge the yellow line of any air until freon comes out
- Slowly open the LOW side valve to restart the charging. Do not open all at once or it could slug the compressor.
- Once the can is empty or the car is at the proper charge, close both valves and disconnect them from the HI/LOW sides
- Close the refrigerant can valve completely, and disconnect the yellow line