The side-connection pressure switch, calibration 35/17, is the replacement part for the water level control system in professional dishwashers. Its job is to sense the air pressure in the level chamber, which varies with the water level in the tank, and accordingly trigger the fill solenoid valve to open or close, keeping the water level correct during the wash cycle.

Replace it when the machine no longer fills with water, when the water level is insufficient resulting in ineffective washing (dishes remaining dirty), or when the control board reports a water level error. The side connection allows fitting on models where the pressure-sensing tube connects from the side.