Chromatography Forum

Hi Aldehyde,

Part of what you're describing sounds like part of the leak test in the G1888 documentation (checking for a stream of bubbles or lack thereof out the vent). Thank you for the suggestion of actuating the valves and looking for what types of actions will affect the size and shape of the peak... it is now definitely on my list of things to try.

I have the cede access to the instrument now for probably a couple days, but when I can have it back I will try some of these ideas and report back.

Stephen

I tried manually actuating the valves and I didn't see anything "interesting" travel down the column, so that's either good or bad, depending on your point of view. I'm still trying to get Agilent to give me a part number for a suitable plug for the 7mm nut and/or ZDV union so I can plug off the little bit of carrier tubing to the inlet and try connecting the transfer line via the needle. It's like pulling teeth, you'd be amazed. Still no luck, but I might be making progress.

Stephen

Well, changing the probe, the ZDV union connecting to the probe, the deactivated tubing from the probe to the 6 port valve and the solenoids to the 6 port valve and the 1 mL loop did not fix the issue, and apparently neither did routing the transfer line directly through the inlet septum via the HSS needle and plugging off the end of the former carrier gas line.

So, now I'm stumped. I'm doing some further experiments to see if this configuration reduces the little bit of extra tailing I've also seen since switching to the EPC carrier setup.

Any other suggestions of what I could try?

Thanks,

Stephen