Replacing The Check Valve Cartridges - Thermo Scientific Dionex UltiMate 3000 Series Operating Instructions Manual

UltiMate 3000 Series:
NCS-3500RS and NCP-3200RS

7.5 Replacing the Check Valve Cartridges

Two check valves are installed in the pump head: inlet check valve and outlet check valve
(→ Fig. 65, page 184, nos. 11 and 13).
Description
Check valve cartridge, ceramics, for the NC pump and loading pump
(the cartridge is the same for both the inlet and outlet valve)
Check valve cartridge, sapphire, for the NC pump and loading pump
(the cartridge is the same for both the inlet and outlet valve)
Valve nut kit (inlet check valve nut and outlet check valve nut) for
NC pump and loading pump
1. If necessary, purge the pump to remove harmful solvents.
2. Set the pump flow rate to 0.
Open the related purge valve to the stop to reduce the pressure down to zero.
3. Put on a pair of clean room gloves to prevent contamination on the valve parts. Even
minute particles may cause damage to the system and result in poor pump
performance.
4. Disconnect all tubing connections from the inlet and outlet check valves. Observe the
information about the different fitting connections on page 57.
To remove the capillary on the outlet valve nut, consider disconnecting the other end of
the capillary (on the rear (lower) connection port) first to facilitate the procedure.
5. Loosen the check valve nuts, by using an open-end wrench (size 13), and remove them
from the pump head.
6. Hold the nuts over your hand and turn them upside down, allowing the cartridges to
drop into your hand.
7. Insert a new cartridge into the check valve nut. Make sure that you insert the cartridge
in the direction of solvent flow, as indicated by the arrow on the cartridge.
8. Screw the valve into the pump head and tighten the check valve (recommended
torque: 10 Nm). Do not overtighten; this will crush the cartridge.
Note the following:
NC pump
Optional: Installation of the inlet check vale may be easier while the pump head is
removed. For information about how to remove and reinstall a pump head, see
section 7.6.2 (→ page 188).
Tighten the inlet check valve hand-tight and turn the bottom part so that the inlet opening
points to the back right. Then, use an open-end wrench (size 13 mm) to tighten the nut
until the inlet opening is on the front left (→ Fig. 64, page 183).
Page 182
Part No.
6041.2301
6041.2300
6042.7007
Operating Instructions