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Thermo Fisher Scientific

IC Pump Low Pressure

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Issue

Low or Fluctuating Pressure on IC Pump.

  • Leaking Check Valve
  • Stuck Check Valve
  • Dirty Check Valve
  • Defective Check Valve 

Environment

  • ICS1100
  • ICS1600
  • ICS2100
  • Aquion
  • ICS5000
  • ICS5000+
  • ICS6000

Resolution

Leaking Check Valve-    Tighten Check Valve.

Stuck,  Dirty or Defective Check Valve-   

 

To Replace the Check Valve

1. Turn off the pump from the Chromeleon ePanel.


2. Turn off the Dionex Aquion RFIC main power switch.


3. To prevent contamination of pump parts, put on standard disposable laboratory rubber
gloves (powder-free, particle-free, and oil-free) before disassembling the pump head.

Note Never disassemble the pump head with bare hands. Even minute particles of
dust or dirt on the check valves or piston can contaminate the inside of the pump
head and result in poor pump performance.

4. Disconnect the tube fittings from the inlet and outlet check valve assemblies on the
primary pump head. 

 

5. Using a 1/2-inch wrench, loosen both check valve assemblies. Remove the check valve
assemblies from the pump head.

Note The inlet check valve assembly housing has a 1/4-28 port. The outlet check valve
assembly housing has a 10-32 (smaller) port 

6. If you are installing new cartridges (P/N 045994) in the existing check valve housings:
• When placing the cartridge in the inlet check valve housing, be sure the double-hole
end of the cartridge is visible. If it is not, remove the cartridge from
the housing and install it correctly.
• When placing the cartridge in the outlet housing, be sure the single-hole end is visible
 If it is not, remove the cartridge from the housing and install it
correctly.

IMPORTANT If you do not orient the check valve cartridges correctly, the pump will
not operate properly (and may be damaged). Liquid must enter the check valve
through the large single hole and exit through the small double holes.

 

7. Install the inlet check valve assembly on the bottom of the primary pump
head.
8. Install the outlet check valve assembly on the top of the primary pump
head.

9. Tighten the check valves finger-tight, and then use a wrench to tighten an additional
one-quarter to one-half turn.

IMPORTANT Overtightening may damage the pump head and check valve housing
and crush the check valve seats.

10. Reconnect the liquid lines.


11. Close the front door.


12. Turn on the IC main power switch.


13. Prime the pump

14. When the system is at operating pressure, check for leaks from the check valves. Tighten a
check valve a little more only if it leaks.

 

 

To Clean the Check Valve

1. Carefully remove the check valve cartridges from the valve housings.


2. Place the check valve housings and cartridges in a beaker with methanol. Sonicate or
agitate the parts for several minutes.


3. Rinse each check valve housing and cartridge thoroughly with ASTM filtered, Type I
(18 megohm-cm) deionized water.


4. To reinstall the check valves and complete the procedure, see Step 6 through Step 14
above.