Hitachi ChromasterUltra Rs 6270 Instruction Manual page 64

2.2 Operating Principle and Functional Description
(j) [When two wash fluids are used]
Wash of the injection port flow path with the wash fluid2.
Switch the 3-way solenoid valve to the wash fluid2 side.
Deliver the wash fluid2 via the needle to the injection
port with the wash pump to wash the flow path of the
buffer tube, the needle inner wall, and the injection
valve.
Figure 2-21 Washing the Injection Port Flow Path with the Wash Fluid2
2 - 24