Replacing A Pump Piston; Replacing The Waste Valve Or Priming Valve O-Ring - Thermo Scientific Dionex Aquion RFIC Operator's Manual

Replacing a Pump Piston

Replacing the Waste Valve or Priming Valve O-Ring

Thermo Scientific
3. To seat the seal, push down on the spacer until it is flush with the head. A clicking sound
indicates that the seal is correctly seated.
4. Close the priming valve knob or waste valve knob.
To reinstall the pump head and piston

Thermo Fisher Scientific recommends reinstalling the pump head and piston as a single
assembly. This allows the piston to center itself onto the magnetic follower.
1. Hold the assembled spacer and seal guide with the drain tubes aligned vertically and press
the spacer into the head until it is flush with the indented surface of the head.
2. Insert the piston so that 6 mm (1/4 inch) of the shaft is exposed. This ensures that the
magnet in the follower picks up the piston. (The follower is the cylinder that holds the
piston in place as it moves in and out of the pump head assembly.)
3. Reinstall the head and piston assembly. Use a wrench to tighten the nuts evenly (12 in-lb
torque).
To complete the procedure

1. Reconnect all liquid lines to the pump head.
2. Turn on the Dionex Aquion RFIC main power switch.
3. Prime the pump (see
Continued leaking of the piston seal after installation of a new seal (assuming the pump head
is tight) indicates a dirty, scratched, or broken piston.
Follow the instructions in
to install a new piston (P/N 052840) and piston seal (P/N 055870).
A damaged O-ring causes leakage around the base of the waste valve knob (on the primary
pump head) or priming valve knob (on the secondary pump head).
To replace the waste valve or priming valve O-ring

1. Turn off the pump from the Chromeleon ePanel.
2. Turn off the Dionex Aquion RFIC main power switch.
"Priming the Pump (Standard Procedure)"
"Replacing a Pump Piston Seal and Piston Rinse Seal"
Replacing a Pump Piston
on page 90).
on
Dionex Aquion RFIC Operator's Manual
6
Service
page 78
83