Alliance HPLC System fails injector linearity and accuracy test - WKB200286

SYMPTOMS

• Successful linearity test with R^2 > or = 0.9990
• Accuracy test failure indicates a problem with the y-intercept or slope of the line
• Replacing the injector assembly does not help

ENVIRONMENT

• Alliance HPLC System
• 2695 Separations Module
• 2795 Separations Module

CAUSE

Faulty syringe assembly

FIX or WORKAROUND

Replace the 250-µL syringe assembly (WAT073109).

ADDITIONAL INFORMATION

The faulty syringe demonstrated irregular resistance over the range of movement—possibly non-uniform surface in the bore of the glass barrel.

Wetting the PTFE plunger tip before inserting it into the glass barrel can mitigate wear to the tip.