Help a QDa rookie

I am 90% sure i change the switch to flow to waste after i shut iff the QDa for the weekend.  But i have started to doubt myself.  The uplc was left running through at 0.1ml/min with a wash. What damage could happen if this system kept flowing into a shut off QDa? 


  • Pflan
    Hi Shufty45,

    I consulted two experts within Waters on your behalf...their responses are:

    "Whilst we recommend that mobile phase is never introduced into the QDa when the instrument is outside of Operate, it is very unlikely that flow with supported solvents etc at 0.1 mL/min will cause damage to the instrument. Liquid flowing into the source when the gases are off should flow into the waste bottle via the convoluted tubing and not cause damage to the QDa."

    "The danger is that the instrument could have been flooded.  If the instrument has been flooded it is unlikely it would pump down and if it did sensitivity would be dramatically lower. In short you would know form their results if its been damaged.

     However, the gas fail features should have prevented any damage occurring to the system."