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 air flow vacuum pump is easy to operate and pulls full vacuum within two mins of being linked to an air series. Includes 1/2 in. ACME (R134a) and R12 connectors.
Air-powered vacuum pumps work when compressed air passing via an orifice increases its velocity and lowers its air pressure. Ambient air flow is used through channels in the generator, creating suction and vacuum. The air stream exits through the exhaust. … These operations require vacuum pumps.