108 1100 Series Nano Pump Service Manual
3 Repairing the Pump
Simple Repair Procedures
The procedures described in this section can be done with the nano pump in
place in the system stack.
Table 14 Simple Repair Procedures
Procedure Symptom Notes
“Exchanging the Active Inlet Valve Cartridge
or the Active Inlet Valve” on page 109
If internally leaking Pressure ripple unstable, run leak test for
verification
“Exchanging the Outlet Ball Valve Sieve or
the Complete Valve” on page 112
If internally leaking Pressure ripple unstable, run leak test for
verification
“Installing the Manual Purge Valve” on
page 114
Unstable column flow or
system pressure
“Installing the Manual Purge Valve” on
page 114
Column flow and system
pressure drops from time
to time.
A pressure drop of > 10 bar across the frit
(2.5 ml/min H
2
O with purge open) indicates
blockage
“Exchanging the Pump Seals and Seal
Wear-in Procedure” on page 122
If pump performance
indicates seal wear
Leaks at lower pump head side, unstable
retention times, pressure ripple unstable — run
leak test for verification
“Exchanging the Plungers” on page 125 If scratched Seal life time shorter than normally
expected — check plungers while changing the
seals
“Exchanging the Flow Sensor” on page 126 Extended flow range
(100 µl) needed.
Leak on the flow sensor.
Unstable column flow
Flow sensor blocked