ACQUITY UPLC gives different peak shapes with repeat injections from the same well - WKB204426

SYMPTOMS

• Different peak shapes with repeat injections from the same sample well
• Dynamic leak test passes to vent valve, fails to port 6 on the injection valve cartridge
• Dynamic leak test fails when filter outlet is blocked
• Dynamic leak test passes when vent valve to filter outlets are blocked

ENVIRONMENT

• ACQUITY UPLC I-Class
• ACQUITY UPLC I-Class PLUS

CAUSE

Defective mixer

FIX or WORKAROUND

1. Replace the mixer and the vent valve-to-mixer tubing (700005341, 430001207, 430001208).
2. Repeat the dynamic leak test.

ADDITIONAL INFORMATION