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