Bio-Rad BioLogic DuoFlow Pathfinder 80 System HR Gradient Pump Maintenance Kit - Manual (Page 3)

Figure 3. Pump Head Module Assembly
3. Replacing the Piston Wiper
Piston wipers are available in the event that they are lost during any of the pump maintenance
procedures. If the piston wiper has fallen out of the spring retainer, simply place a new piston
wiper onto the piston which then rests on the spring retainer. See Figure 1.
4. Plumbing the Gradient Pump
a.
For inlets to the Gradient Pump, it is essential to use the wide-bore tubing supplied with your
system, which is 1/8” OD (0.062” ID)
37)(
.
Note: Using smaller bore tubing will not provide sufficient flow of liquid to the Gradient Pump.
This will lead to entrapment of air bubbles in the pump heads which in turn causes an erratic
delivery of liquid and may stall the pump.
b. The remainder of the Gradient Pump system is plumbed with 1/16” OD (0.020” ID) Tefzel
tubing.
Daily Maintenance
Washing behind the piston seal extends seal life. Insert a 10 ml syringe filled with deionised water
in the Washout Port luer fitting. Each pumphead should get a 10 ml washout once per day,
preferably at the end of the day's operation. Run off water exits the pump through the Washout
Drain between the two pump heads. It can be collected in a small beaker.
PUMP HEAD
MODULE
ASSEMBLY
SCREWS
OUTLET HEAD
PUMPING HEAD
PRIMING HEAD
CHECK VALVE
CHECK VALVE