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Loud noise comes from ACQUITY QDa pinch valve assembly (KAD model) - WKB75987

Article number: 75987

SYMPTOMS

  • Excessive noise comes from the QDa internal exhaust pinch valve assembly (KAD model)
  • The instrument operates normally without error messages
  • The source pressure test passes
  • Noise is continuous during routine system operation
  • Nitrogen consumption is higher than normal
  • Nitrogen inlet pressure unstable when the QDa is in Operate mode
  • Nitrogen leakage can be sense from the drip tray.

ENVIRONMENT

  • ACQUITY QDa Mass Detector

CAUSE

Faulty or leaking internal pinch valve assembly

Audio file of nitrogen leaking through internal pinch valve:

QDa pinch valve leak N2.m4a

FIX or WORKAROUND

Reseat the pinch valve, tightening the four hex screws.

It reseating does not work, replace pinch with valve part number: 700011173

 

ADDITIONAL INFORMATION

See the ACQUITY QDa Overview and Maintenance Guide for replacing the Internal Pinch Valve Assembly.

If reseating doesn't work, replace the KAD model internal pinch valve assembly - WKB120623

id75987, QDA

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