Low sensitivity in EPA tune on 7900

This instrument has been having issues with low sensitivity but only with EPA tune. As you can see, the Agilent tune solution (1ppb) returns good results, but the EPA tune solution (10ppb) is terrible. This was run with brand new cones, conditioned, and is the highest results I've ever seen. Today, my mass 9 counts were.. 9. 9!. What can I do to improve them?

The morning routine is:

Torch Axis, EM, Plasma Correction, Standard Lens Tune, Resolution/Axis, Performance Report with Agilent tune solution. Then another Resolution/Axis with EPA tune solution. Then tuning He and H2 gas modes in the Batch tab.

Copy of my Performance Report:

I've changed basically everything I can. Different nebs, different spray chamber, torch, and x lens.

  • This look like it's only bad tuning parameters.  Try to have another tune file for EPA. Also, you are doing dilution with EPA.  You should start with the wizard method to see if you can fix this. it has the tuning parameters.  You don't need to perform resolution and axis with the EPA tune has it might be what is killing your sensitivity.

    Also, you should have the checkout batch with the installation of instrument.  Try this batch to see if instrument is working.  If it's working, then it's your tune parameters for EPA that are killing sensitivity.

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