High delta psi pressure fluctuations cause gradient test to fail on H-Class QSM - WKB28511

SYMPTOMS

• GPV test fails
• High delta psi
• Pressure drops to 0 psi
• The following parts were replaced without improvement:  column, active preheater, GPV, GPV filters, tubing from GPV to manifold, pump head seals, i2V check valve, passive check valve, primary actuator, accumulator actuator

ENVIRONMENT

• ACQUITY UPLC H-Class
• ACQUITY UPLC H-Class Quaternary Solvent Manager (QSM)

CAUSE

Faulty degasser pump

FIX or WORKAROUND

Replace the degasser pump (700001352).

ADDITIONAL INFORMATION