Force the Call for Water

Remove the probe wire from the probe terminal. The level control board should call for water.

Force the Call for Steam

Short between the Probe and GND terminals and you should hear the heater contactor pull in (if the pressure switch is calling for steam). (Be sure to turn off the high voltage power to the boiler so you do not energize the element dry by mistake)

The same techniques can be used to verify the operation of the LWCO board.

The current design only allows the LWCO board to be powered when the Level Control Board detects water.

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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