The air vacuum pump is a venturi-type AC pump that eliminates moisture from air conditioning systems, making it safe and simple to add refrigerant. The atmosphere vacuum pump 
is easy to run and pulls complete vacuum within two minutes of being linked to an air line. Includes 1/2 in. ACME (R134a) and R12 connectors.
Air-powered vacuum pumps work when compressed air moving via an orifice increases its velocity and lowers its air pressure. Ambient air is drawn in through channels in the generator, creating suction and vacuum. The surroundings stream exits through the exhaust. … These operations require vacuum pumps.