"Pump Bad State" error on Alliance iS - WKB294050

SYMPTOMS

• "Pump Bad State" error appears on startup
• Bypassing inlet filters and re-initializing solves the issue

ENVIRONMENT

• Alliance iS HPLC System

CAUSE

Blocked inlet line filter

FIX or WORKAROUND

Replace the inlet filter (700002913).

ADDITIONAL INFORMATION

Blocked inlet filters result from poor solvent practices—most likely aqueous mobile phase that was left on the system too long, or immiscible solvents.

Remember: Filters do not block themselves; they are always blocked by introduced contaminants.