How to Create a Temporary Vapor Port

Select a 400 Department of Transportation (DOT) vapor recovery cylinder with high pressure capabilities and a constant pressure regulator (CPR) valve to automatically regulates vapor flow. Look for portability and a condenser large enough to keep the cylinder's tank unit cool.

Confirm that the certification term of the cylinder has not expired.

Check the recovery cylinder and valve for dents or corrosion.

Connect a yellow hose from the low-side service port of the heating, ventilation and air-conditioning (HVAC) system to vacuum the system before creating a vapor port to avoid a build-up of acids in your evaporator. Connect the other end of the hose to the center port of the manifold set, also known as the charging port.

Connect the blue hose from the low-pressure side of the manifold system to the suction side of the recovery cylinder so that you connect the compressor to the evaporator.

Locate the high side service port on the manifold system. Connect a red hose from the tank vapor port to the high pressure side gauge on the manifold set.

Close the valves on manifold set.

Open the low side gauge vapor and liquid valves on the recovery cylinder. Turn on the vacuum pump. Watch the gauge needle move towards vacuum as it starts the recovery system.

Run the vacuum pump and monitor the tank pressure for approximately 30 minutes. Ensure that the gauge reading of 20 to 30 Hg. If not, check your connections to rule out a possible leak.

Close all valves. Turn off the vacuum. Disconnect the hoses from the HVAC system.

Place the recovery cylinder freestanding on the electronic charging scale as your temporary vapor port. Weigh the empty recovery cylinder. Calculate the maximum filling capacity at a pressure of 80 percent liquid at 77 degrees Fahrenheit because the liquid refrigerant will expand.

Open the cylinder valve to fill the recovery cylinder to create a temporary vapor port.

Shut off the valve when you reach the maximum weight. Close the cylinder valve. Weigh the cylinder.

Tag the cylinder with the content identification.