Sample manager not reaching required temperature

<p>Hi!</p><p></p><p>Does anybody know why in the calibration of the sample manager specify that the temperature to be tested can not exceed 20 deg below ambient temperature?</p><p>we were trying to run a test that has been run before and this time the sample manager was not reaching the 4 deg required. The temperature in the lab was increasing, a t some point was 20 deg, then was 25. Is it really becuase of the difference between temperatures? Why is that?</p><p></p><p>Thanks!</p><p></p><p>DDL </p>


  • RD

    The specification of the ACQUITY Sample Manager reads as follows:

    SM Temp.jpg


    So, assuming door seals have not been breached, I would expect you to be able to reach 4 degrees.

    For the optional Sample Organizer (plate/rack feeder), the spec is a bit more restrictive:

    SO Temp.jpg

    Thermoelectric cooling, like that used in many, if not most, liquid chromatography autosampler compartments, is a relatively inefficient process compared to vapor-compression refrigeration (like that used for air-conditioners and refrigerators).  Among other things, it is dependent upon ambient temperature and specifications for devices employing it always reference the ambient temp.  It used because for this application, the advantages of compact size, no maintenance or moving parts, and low cost outweigh efficiency.

    If you have not had Preventative Maintenance done to the unit in more than a year, you might consider it.  At the very least, make sure the unit's are filters are clean and the fans on the unit are free of dust.

    The complete ACQUITY spec sheet is attached.



  • Thank you for your answer!


  • You can also "defrost" your column manager. In some cases, it may help. Otherwise, if your system is an older one, e.g. 2 or 3 years old, the peltier element might be broken. Call your friendly Waters dealer and ask for support.