Leakage of "Metering Syringe Valve" and problems with weak wash syringe

<p>Hello!</p><p style="height: 8pt"/><p>We have trouble with our UPLC system and we hope that someone in the community can help us. </p><p style="height: 8pt"/><p>It started with a leakage in the Metering Syringe Valve during the washing of the sample needle after injection. Then the 2.5 mL wash syringe started to draw air although there was sufficient liquid in the reservoir bottle. During pressing out the weak wash we could observe air bubbles in the weak wash reservoir bottle. </p><p style="height: 8pt"/><p>We mentioned this problem to a Waters Germany technician and he figured it to be a damaged Metering Syringe Valve. So we ordered a new one and changed it this morning. Now during performing the priming of the wash solutions, the same problem occured (without the leaking of the valve!). Priming weak wash led to approx. 500 uL wash solution in the weak wash syringe, priming strong wash led to 2 mL solution in the weak wash syringe. In both cases while pressing out of the liquid we could observe air bubbles in the reservoir bottle. In addition, now the sample syringe draws air too... </p><p style="height: 8pt"/><p>Have you any ideas? Could it be a blocked tubing? If yes, were can we look? </p><p style="height: 8pt"/><p>Many thanks in advance!</p><p style="height: 8pt"/><p>Sincerely</p><p>Susanne </p><p></p><p>Edit: We now checked the tubings and they seem to be ok. Can it be because of a malfunction in the "Valve Manifold"? </p>


  • Hi Susanne,

    There may be a problem with you replacement SMV.

    During a weak wash syringe diagnostic test, the strong solvent is flushed backed through the valve manifold and to the reservior

    During a strong wash syringe diagnostic test , the weak solvent is flush back thought the valve manifold and out the wash station to waste.

    So to confirm whether this the issue is isolated to the SMV and to confirm the SMV is good or bad, repeat these tests, do they fail? If they do next remove the tubing form the SMV inlet and outlet , replace it with a peek union and perform the test again, if the tsets pass then the SMV is bad.

    Let us know.


  • Hi Liz,

    thank you for your suggestion. But unfortunately I'm not sure how to perform this diagnostic test. I haven't found it in the manual or in the MassLynx software. There are only tests for pressure and leaking... Were can I find it? While performing the test, does it run automatically or do I have to check directly at the tubings if there is a flow or not?



  • Hello Susanne -

    The Sample Metering Syringe Leak Test is located as a pull down menu choice in the ACQUITY Console. Two additional tests that may characterize this are the Weak Wash Syringe Leak Test and Strong Wash Syringe Leak Test. However if air is continued to be drawn during priming, I suspect these test will not pass. It may be worthwhile to request a Field Service Engineer review the instrument components.

    Dave D.

  • Hi there!

    Thank you all for your suggestions.

    I requested a Field Service Engineer and hopefully he can locate and fix the problem!

    Yours Susanne

  • I'm having a similar problem but I am unable to find these tests. Are these tests only visible with the 1.4 v firmware? I have v1.3.

    Thank you!

  • Hi Melissa

    Yuo should be bale to find this function in ver. 1.3 as well. Go to sample manager > maintain > leak test > "ample syringe in the console. Check the attched picture.

    Best regards