The analytical pump head delivers eluent to the remainder of the chromatography system (the injection valve, column, and detector). The priming valve is on the front of the pressure transducer (see the following figure).

The pump head assembly is comprised of two pressurizing features. The left-most side, which provides the inlet primary pressure, is connected to the right side of the pump head for the secondary pressure. The primary pump feature receives flow from the bottom, through an inlet check valve, and then delivers liquid flow out through the outlet check valve on the top of the pump.

To open the priming valve, turn the knob one-quarter to one-half turn counterclockwise. When the priming valve is open, liquid can flow into and out of the primary pump head via the port at the bottom of the transducer block.

Figure Dionex Inuvion IC System analytical pump assembly (pump to the left, pressure transducer to the right)
Dionex Inuvion IC System analytical pump assembly (pump to the left, pressure transducer to the right)

NOTE

The prime valve must be open when the pump is being primed using the Prime button. This allows any trapped air to escape the system.