Bio-Rad Profinia™ Protein Purification Instrument - Manual (Page 155)

Cleaning and Replacing Outlet (Top) Check Valves
Fig. 13.5. Diagram of the outlet check valve.
To clean or replace the outlet check valve:
1. Remove the tubing fittings from the top of the outlet check valve.
2. Using your fingers or a 9/16" open-end wrench, unscrew the outlet check valve from the
pump body.
3. Hold the check valve body with a 9/16" open-end wrench, and loosen the threaded
insert with a 7/16" open-end wrench.
4. Unscrew the threaded insert from the valve body. The insert has a concave surface
with a hole in it. Set the insert aside in a safe place.
5. Look into the cavity of the check valve body; you will see a tan-colored disk with a
rubber “button” facing toward you. Turn the check valve body over and tap it on the
benchtop to remove the plastic disk and button from the valve body.
6. Gently pull the black button from the disk, using your fingertips.
7. Examine parts for damage; replace the check valve if necessary.
8. Using your fingers, gently replace the rubber button in the plastic disk. Take care to
center the head in the disk. The plastic disk is the same on both sides.
9. Replace the disk in the check valve body, with the black rubber button toward you.
10. Thread the insert into the check valve body and tighten, using the two wrenches as
described in step 3 above.
Note: Do not overtighten the insert.
11. Thread the assembled check valve into the pump body, and tighten with a 9/16"
open-end wrench.
12. Reconnect the tubing to the check valves.
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