Air Removal

Before any steam sterilization cycle the air must be removed.  There are two methods of removal and Consolidated offers both methods.  On method is called gravity air removal where, in the initial purge cycle of the sterilization process, all air is removed from the chamber by gravity displacement (steam pushes the air out of the chamber).

The second method of air removal is created with a vacuum system (used on sterilizers that have a “pre-vac” cycle.).  A vacuum system is recommended, and often required, when sterilizing goods which are difficult for steam to penetrate or require a long drying period.  Read more about Gravity vs Vacuum here: Part of Blog Series on Air Removal 

In summary, the available air removal options are listed below:

  • Option 1: Gravity Air Removal:

    • Standard on all units.
  • Option 2: Vacuum Air Removal with Water Ejector:

    • Optional upgrade.
    • Recommended for items that are porous (animal bedding, containers with small openings, objects with unsealed lids, packs, lumens, tubing).
    • Draws air from chamber prior to cycle, and can also perform post-vacuum drying.
    • Utilizes the venturi effect to draw air from the chamber down the drain manifold.
    • Can perform Vacuum Leak Test and Bowie-Dick test.
    • Lower upfront cost than Liquid Ring Pump (see below) but will consume more water.
    • No electrical utilities required if facility has adequate water pressure (above 45 psig dynamic).
    • Takes up the least amount of space under the sterilizer
    • If facility does not have enough water pressure, a booster pump may be supplied by CSS
  • Option 3:   Vacuum Air Removal with Liquid Ring Pump:

    • Optional upgrade.
    • Recommended for items that are porous (animal bedding, containers with small openings, objects with unsealed lids, packs, lumens, tubing).
    • Can perform Vacuum Leak Test and Bowie-Dick test.
    • Capable of pulling a deeper vacuum than the Water Ejector.
    • Higher upfront cost over a Water Ejector for a much larger complex piece of equipment, however saves more water.  (Water savings will allow the unit to pay for itself over time.)
    • Requires 3ph hardwire connection (voltage options: 208/240/480)
    • Consolidated’s liquid ring pump is a robust solution that ensures a strong vacuum each and every cycle.   The liquid-ring pump compresses gas by rotating a vaned impeller located eccentrically within a cylindrical casing.  Water is fed into the pump and, by centrifugal acceleration, forms a moving cylindrical ring against the inside of the casing.
    • Consolidated uses a brass/bronze pump head on our liquid ring pump. Many manufacturers use a cast iron pump head, which can lead to service issues. (If they sit idle for a period of time then rust forms on the cast iron pump heads. Significant damage or failure can occur with a rusted cast iron pump head.)


Premium Hi-Vacuum (Liquid Ring Pump) Standard Hi -Vacuum (Water Ejector) Economy Post-Vacuum (Water Ejector)
Description Utilizes a liquid ring pump to efficiently and quickly pull a vacuum Utilizes a water ejector to pull a vacuum, Booster-pump included if water pressure is < 45psi Utilizes VenturiJet to efficiently and economically provide a post vacuum drying option
Advantages Removes air more efficiently, Greater controllability, Less water Less expensive, Low maintenance Very economical for applications that require only PostVac Drying, Very low maintenance
Disadvantages Cost & Maintenance Water consumption No Pre-Vac capabilities, Water pressure (45 psi min.)
Pre-vac Yes Yes No
Post-vac Yes Yes Yes
Vacuum Leak Test Yes Yes No
Bowie-Dick Test Yes Yes No