Vacuum filling unit consists of

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1) Filling unit with vacuum meter and shutoff valves
2) Filler hose
3) Coolant container
4) Venturi nozzle
5) Compressed air connection (max. 6 bar)
6) Outgoing-air hose (lead outgoing-air hose into a collecting container)

Fig 1: Identifying Vacuum Filling Unit Components
Courtesy of BMW OF NORTH AMERICA, INC.