Pressure drops and intermittent B-channel flow on ACQUITY H-Class Quaternary Solvent Manager (QSM) - WKB281323

SYMPTOMS

• Pressure unstable when channel B is selected
• Intermittent flow on channel B even when priming, but all other channels are fine
• All other channels pass DLT

ENVIRONMENT

• ACQUITY H-Class Quaternary Solvent Manager (QSM)

CAUSE

Debris or precipitation in B-channel degasser and/or GPV

FIX or WORKAROUND

1. Remove the channel B sinker from the mobile phase.
2. Remove lines from the channel-B degasser and GPV.
3. Back flush lines, degasser, and GPV (ensure that GPV is open; QSM must be powered-on and solvent B selected).
4. When all lines are flowing clear, reconnect, prime, and ensure that prime flow is constant and steady.
5. Run the pump leak test to ensure that no other leaks were created during disassembly or reassembly.

ADDITIONAL INFORMATION

If above procedure fails to clear the blockage, replace the following:

• 700005161 - Assy, GPV, Dual Channel
• 700011667 - Degasser, Single, TI Stented, 18-inch AF

Article related to this issue:

Pressure fluctuations on ACQUITY H-Class QSM - WKB19400