Thermo Scientific Dionex ICS-2000, Operator'S Manual

Page: 126 / 390

ICS-2000 Ion Chromatography System
5-16
Doc. 031857-03 4/06
5.5 Cleaning and Replacing the Pump Check Valves
A dirty check valve causes erratic flow rates and pressures. In addition, it
may cause the pump to lose prime and/or be difficult to reprime. If possible,
replace dirty check valves. If new check valves are not available, follow the
instructions for cleaning.
Replacing Check Valves
1. Close the eluent valve from the ICS-2000 Control panel in Chromeleon or
select Eluent Valve Closed on the touch screen
PUMP
page.
2. Turn off the main power switch, to ensure that you do not unintentionally start
the ICS-2000.
3. To prevent contamination of pump parts, put on a pair of rubber gloves before
disassembling the pump head.
4. Disconnect the tube fittings from the inlet and outlet check valve assemblies
on the primary pump head (see Figure 5-11 ).
5. Use a 1/2-inch wrench to 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 port.
Figure 5-11. Pump Heads
Secondary
Pump Head
Primary
Pump Head
Outlet Check
Valve
Inlet Check
Valve
Acorn Nuts