Pressure fluctuations on ACQUITY H-Class QSM - WKB19400
Article number: 19400
SYMPTOMS
- Pressure fluctuates on both Accumulator and System pressure traces
- Delta still within 1% of system pressure but higher than usual and unstable
- Can increase baseline noise on UV detectors
- Dynamic leak test passes
- Replacing check valves doesn't solve the problem
ENVIRONMENT
- ACQUITY H-Class Quaternary Solvent Manager (QSM)
CAUSE
Blockage in gradient proportioning valve (GPV).
Affects either A/B solvent lines or C/D solvent lines
When closing GPV from Acquity Console, some solvent is still flowing through the affected line
FIX or WORKAROUND
Replace the dual-channel GPV (700005161) for the affected solvent lines.
ADDITIONAL INFORMATION
