Low peak heights

[LaytonAnnMarieDV]

One of the ICs (858 Professional Processor) is recovering low peak heights. The results have been passing (for the most part), but the heights have been low.

Typically, they would run around 26, 22 and 10 μS/cm for chloride, nitrate and sulfate, respectively. Now, they're around 5,3 and 2 μS/cm.

I have checked every tubing for air bubbles and done everything else I can think of with no luck. I'm thinking it might be a conductivity detector issue. Any thoughts? TIA

[peterbopei85]

Did you check the baseline level, if the background of baseline is too high, the signal of ions would be lower, right？I think you need to check the suppressor if it was breakdown first.

[LaytonAnnMarieDV]

Did you check the baseline level, if the background of baseline is too high, the signal of ions would be lower, right？I think you need to check the suppressor if it was breakdown first.

The baseline is the same as it was before the heights plummeted. A new suppressor has been installed, and the heights are still low.

[anionman]

My ICS-02100 peaks started broadening before the thing died a few years back. The guy from Thermo wasn't sure what the problem was so he said he would just keep replacing parts until it worked. he said our detector was bad and that was very rare. But even after replacing the detector it didn't work. So he replaced the degasser and took off our carbonate removal device and it started working fine.

[LaytonAnnMarieDV]

My ICS-02100 peaks started broadening before the thing died a few years back. The guy from Thermo wasn't sure what the problem was so he said he would just keep replacing parts until it worked. he said our detector was bad and that was very rare. But even after replacing the detector it didn't work. So he replaced the degasser and took off our carbonate removal device and it started working fine.

Thanks for the info. I had thought about replacing the detector, so I'm going to give that a shot since it's an easy swap. After that, I can look into the degasser and other items.

[itspip]

While waiting for a new detector you could try to flush is with dilute nitric acid solution (~1%, someone please correct me if I'm wrong here). A company I worked for once cleaned one from a different site to use and that seemed to do the trick.

[Nadine Seifert, MIHQ]

You mention the peak heights, that they are decreased. What about the peak areas? Are they still the same?
What type of injection are you using? Full loop injection?

[LaytonAnnMarieDV]

So, a new conductivity detector did not fix the issue.

The peak areas have also gotten smaller since this issue started.

I am using a full loop injection from what I know.

[anionman]

So, a new conductivity detector did not fix the issue.

The peak areas have also gotten smaller since this issue started.

I am using a full loop injection from what I know.

How old is your suppressor? You could try changing that before trying the degasser.

[LaytonAnnMarieDV]

So, a new conductivity detector did not fix the issue.

The peak areas have also gotten smaller since this issue started.

I am using a full loop injection from what I know.

How old is your suppressor? You could try changing that before trying the degasser.

The suppressor was replaced when this issue started and nothing changed. I also changed the MCS out with no luck there, either.