Replace the Solvent Selection Valve (Isocratic Pump)

When

If leaking internally (crossflow between the ports), or if one of the channels is blocked

Tools required

Qty.		p/n	Description
1		8710-0899	Screwdriver Pozidrive Shaft

Parts required

Qty.		p/n	Description
1		5067-5895	Solvent selection valve

Prerequisites

Lift solvent bottles out of the solvent cabinet and place them on the table. Disconnect the solvent tubes from the solvent selection valve and empty the tubes into the bottles. Place the bottles back into the solvent cabinet.
Disconnect all tubings from the solvent selection valve.
Using a screwdriver, loosen the holding screws of the valve holder.
Carefully disconnect the valve cable at the SSV connector on the Z-Panel.
Using a screwdriver, loosen the holding screws of the degasser front cover.
Carefully pull the valve with a cable out of the pump mainframe.
Exchange the defective solvent selection valve.
Tighten the screws of the degasser front cover and the valve holder.
Reconnect all tubings to the solvent selection valve.

NOTE
After an exchange of the valve it may be required to pump several mL of solvent before the flow stabilizes at a pressure ripple as low as it used to be when the system was still working properly.

21-Jun-2025