BSM pressure failed to decay.... ???

<p><span>Does anyone know what this error message means and how to fix it? It has just occured on our system and I haven't seen it before in 24 months of using the Acquity.</span></p><p></p><p><span>It appears to be a problem with the Column Manger (4 way jobby) as the message is listed under this module. </span></p>


  • lizh

    The "Pressure failed to decay" log message indicates that the column manager is still seeing pressure within a wait time. The valve always vents the pressure before bringing a new column online. This message is used as an indication that the column switch event did not go as planned, and did not fully decompress within the wait time. It waits throws the log message, but continues to operate. It can indicate a flow blockage, or the solvent viscosity issue. Have you changed anything in your operating parameters recently, changed to narrower tubing? Here are some recommendations:

    1. The pressure reading at the end of the run is taken just prior to the run ending. In order to avoid the error and subsequent wait, about 0.25 minutes before the run time ends set the flow to a low value for example 0.1 mL/min this sure ensure the valve actuates as it should.

    2. Ensure the tubing to the detectors is black 0.004"ID and check the lengths.

    3. If using MassLynx, consider a "Switch Method" when going from one column to another set the gradient to go to high organic, flushing previous organic from column, before equilibration with initial conditions of analysis method. We often recommend to set this for the first 1.2 minutes.

    Hope this helps,



    We have seen this error too. We tried to identify if there was a blockage but could not find any. Eventually we switched off the module, switched it back on again and it worked. We have not seen the error since.