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Thermo Fisher Scientific

Pressure Fluctuations

Issue

Pressure fluctuations observed when using IC

Environment

Ion Chromatography

Resolution

Initial investigation should consist of purging the pump with fresh eluent to confirm no air is present within the pump, as the presence of air within the pump may cause fluctuations in pressure. Eluent may then be allowed to progress through the IC system, and the pressure monitored. Check for signs of leaks.

  • If pressure fluctuations are still observed after purging the pump, it is prudent to check the flow through each check valve to confirm good operation
    • If either check valve is showing signs of deterioration, i.e., pulsating flow, the check valves on the primary pump head should be replaced. This should resolve the observed pressure fluctuation issues.
    • If no signs of check valve issues are observed, replace the column set with a length of PEEK tubing (red or yellow) to create approximately 2000 psi backpressure. Monitor pressure under flow rate. If pressure fluctuations stop, column set may need servicing or replacing.