Waters 2489, Operator'S Manual

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4-14 Maintaining the Detector
5. With the tan-colored entrance lens holder curve facing down, use the
torque wrench to tighten the entrance lens screw into the flow cell body
to 0.904 Nm (128 in-oz or 8 in-lb).
6. Flip the flow cell body over to the exit window side.
7. Using plastic tweezers, inspect the second new gasket for cleanliness.
8. Drop the clear plastic gasket into the groove at the bottom of the cuvette
lens end of the flow cell body.
9. Inspect the exit window for cleanliness. Using nitrogen, clean the exit
window, if necessary.
10. Using plastic tweezers, place the exit window into the flow cell body.
11. With the tan-colored exit window holder facing down, use the torque
wrench to tighten the exit window screw into the flow cell body to 0.904
Nm (128 in-oz or 8 in-lb).
Tip: To ensure complete compression of the gaskets, after replacing the
exit window and torquing the exit window screw, and after replacing the
cuvette lens and torquing the cuvette lens screw, you must flip the flow
cell body and torque the entrance lens screw to 0.904 Nm (128 in-oz or 8
in-lb) a second time.
12. Flip the flow cell body again, and torque the entrance lens screw to 0.904
Nm (128 in-oz or 8 in-lb).
13. Flip the flow cell body again to the cuvette lens end, and torque the exit
lens screw again to 0.904 Nm (128 in-oz or 8 in-lb).
14. With the cuvette lens curved side facing up, replace the cuvette lens in
the cuvette lens screw mount.
15. Using your fingers (covered with powder-free finger cots or gloves), place
the split ring onto the cuvette lens and press it firmly until it is flush on
all sides.
16. Using the cuvette tool, screw the cuvette lens screw into the exit lens
screw mount end of the flow cell body.
17. Torque the cuvette lens screw to 0.904 Nm (128 in-oz or 8 in-lb).
18. Follow the procedures in the next section to replace the flow cell into the
flow cell assembly.