- Pressure is higher than normal, with or without column attached
- Pressure decreases when CM-A is set to bypass
- Flushing column-1 tubing in both directions with water and acetonitrile does not resolve issue
- High system back pressure
- Column outlet tubing is pushed from its fitting and results in a leak
- ACQUITY UPLC Column Manager (CM-A)
The tubing between the column outlet and port 3 of the left-hand CM-A switching valve is clogged. (Suspected that the tubing was salted out when switching from aqueous buffer mobile phase to organic mobile phase.)
FIX or WORKAROUND
Replace the Welded Tube Assy, SS, 19.0 LG (700005478).
Part number is the same for all CM-A column outlet tubing—column 1 and 2 outlet tubing.