The picture shows the parts that must be removed.

Replacing an outlet check valve (example, here VF-pump)
Figure: Replacing an outlet check valve (example, here VF-pump)

No.

Description

1

U-tube

2

Outlet check valve, including

2a

Valve nut

2b

Valve cartridge

3

Pump head

When

  • Issue with the check valve that could not be solved by cleaning (for example, persistent leakage)

  • Damage of outlet check valve

Parts required

  • Valve cartridge

  • Valve nut, required only when leakage is present at the fitting connection to the valve

Tools and additional items required

  • Solvent suitable for purging to flush out harmful substances

  • Solvent suitable for your application

  • Open-end wrench, size 13 mm

  • Tweezers, flat tips or curved tips

  • Depending on the capillary connections:

    • Viper capillary: Installation tool for Viper capillaries with torque toothing

    • Conventional capillary (non-Viper): Open-end wrench, size 1/4"

Preparations

  1. To flush out harmful substances, purge the pump with an appropriate solvent.

  2. Turn off the pump flow and wait until the system pressure is down to zero.

    Follow these steps

    1. Remove the capillary that connects the pump head to the purge/sensor unit. Disconnect the capillary on both the pump head outlet and purge/sensor unit.

    2. Remove the U-tube.

    1. Use the open-end wrench to loosen and remove the valve nut from the pump head.

    2. Remove the valve cartridge:

    Valve Cartridge

    Action

    Valve cartridge removed together with valve nut

    Hold the nut over your hand and turn it upside down to allow the cartridge to drop into your hand.

    Valve cartridge remained in pump

    Pull out the cartridge using the tweezers.

    1. Insert the new cartridge into the valve nut. Insert the cartridge in the direction of flow (indicated by the arrow on the cartridge).

    2. Screw the valve nut into the pump head and tighten with the open-end wrench.

    NOTICE

    Overtightening may damage the valve cartridge. The torque should not exceed 10 Nm.

    1. Reinstall the U-tube.

    2. Reconnect the capillary that connects the pump head to the purge/sensor unit. Observe the following:

      Install the capillary in the direction of solvent flow. Note that one end of the capillary is longer than the other end. Connect the longer end to the pump head.

    1. Rinse the pump thoroughly:

      • Use the solvent for your application.

      • Open the purge valve to prevent the rinsing liquid from entering the Vanquish system.

    1. Inspect all flow connections on the pump head for indications of leakage. Tighten leaky connections when the system pressure is down to zero.

    2. Optional: Test the pump for leakage (see Testing the Pump for Leakage (General Test)).