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Thermo Fisher Scientific

How to Replace the Check Valves


  • Leak observed; or
  • Check valves are worn or damaged.


Vanquish HPLC and UHPLC systems


Replace the check valves of your pump whenever they are worn or damaged or you observe a leak.

Required parts:
  • New check valve cartridges
  • New check valve nuts (only in case of obvious damage)
  • Size 13 open-end wrench
  • Tweezers
Preparation steps:
  1. Flush the pump head with an appropriate solvent using the purge function
  2. Turn off the pump flow and wait until the system pressure is down to zero


The Vanquish HPLC and UHPLC systems offer uncompromised performance, robustness, and ease of use. A key element of its user-friendly functionality is the accessibility of the system for simple maintenance and replacement procedures. These videos provide step-by-step instructions on how to perform these procedures and keep your Vanquish HPLC and UHPLC systems operating smoothly. To access these procedures from your instrument, without the need for an external internet connection, consider adding the Vanquish User Interface to your system.


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