The following instructions assume a PSS5 control system
on a PRIMUS sterilizer or a retrofitted PSS5 control kit.

Primary Settings

Go into MENU while in operate mode. If the unit has a vertical touchpad, press the MENU key. If the sterilizer has a horizontal touchpad without a MENU key, touch STER TEMP or STER TIME to get to the MENU.

The following setpoints are needed to run a vacuum cycle

Set the cycle name to VACUUM

Set the number of PRE-VACS at 3 (3 pressure and vacuum pulses) (A minimum of 1 and a maximum of 6 PRE-VACS are allowed with 3 PRE-VACS being standard)

Set the number of POSTVACS at 1 (This enables a post sterilization dry phase)

Set the POSTVACS setpoint at -10.0 (10 inches of mercury vacuum)

If running a 270°F – 273°F (132.2°C) sterilize cycle, use a PRECHARGE PRESS of 20 psig

If running a 250°F (121.1°C) sterilize cycle, use a PRECHARGE PRESS of 10 psig

Typically, set a PREVAC VAC TIME of 1:30

VAC TIME will only occur on the third through sixth PRE-VACS

Set a PREVAC VAC POINT of -20.0 (20 inches of mercury vacuum)

Set a PURGE of 1:30

Refer to the printout below for rough guidelines on other settings.

Depending on what is being sterilized, each end user facility must establish the Sterilize Time and Temperature.

Have a question or having difficulties? Talk to Dave Schall, our PRIMUS sterilizer expert who is here to assist you anytime at 877.679.7800 extension 1212 or email at

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