Waters ACQUITY UPLC Overview And Maintenance Manual page 49

Figure 2–19: Injection valve
Needle tubing (or extension loop tubing, if installed)
4. Fully insert the extension-loop tubing into port 4 of the injection valve, and then thread the
fitting into the port.
5. Holding the extension loop tubing against the bottom of the port, finger-tighten the
extension-loop fitting.
6. Using the 1/4-inch open-end wrench, tighten the extension-loop fitting an additional 1/6-
turn (for existing fittings) or 3/4-turn (for a new fitting).
Note:
Failure to properly bottom the extension loop tubing in the port can result in
carryover or poor chromatography.
Figure 2–20: Extension loop
1
Extension loop union
Extension loop tubing
Extension loop fitting
7. Screw the sample needle's fitting into the extension-loop union, and then use the 1/4-inch
open-end wrench to tighten the fitting 3/4-turn beyond finger-tight (for a new fitting) or 1/6-
turn beyond finger-tight (for existing fittings).
Note:
Failure to properly bottom the sample needle tubing in the extension-loop union
could result in carryover or poor chromatography.
2
3
June 11, 2019, 715005051 Rev. D
Page 49