Chromatography Forum

I feel like an idiot. I haven't done HPLC for a couple years. I'm trying to get my Ultimate 3000 running again. The Chromeleon 7 program is definitely connected to the pump. I was able to purge the pump several times. When I set the flow rate to 0.300 ml/min and click "motor on" it turns green in the program and the display on the pump says "Running %A:100.0" rather than saying off. However, the display on the pump shows 0.000 ml/min and the bar in the software does not register any flow. The pressure is at 0 psi so it is unlikely due to a blockage. I've tried hitting "continue." I feel like there must be a setting I need to click but I can't think of what it would be. A screen shot of the display in the program is below.

Hi 1510NF,

You can try removing the solvent filters and perform a dry prime on all solvent lines. Sometimes the sintered eluent bottle filters may become occluded.

Wouldn't an occluded filter prevent flow during the pump purge? It was flowing at 1ml/min as usual during the purge

Well, I have egg on my face...I'm agreed, yes, if the purge occurs from each solvent line; if the solvent filters were occluded no flow should be observed. I missed that.

Is there another way, please post the "photo" of the screenshot of the display? I get a broken link on this end.

Trying to add image again

Thank You, much better on this end for the screenshot!

Ah, unless I'm misreading the manual for the Ultimate, a second pump is used for system priming.

Please check to see that the Purge Valve is closed. This may be the trouble.

Matt, thank you for all of your time and suggestions! I definitely shut the purge valve after each purge. Your post suggested there are separate pumps for regular flow and purging flow? Hmmm. I wonder if the regular pump is malfunctioning. It seems to be the same motor that switches on, at least in the Chromeleon 7 interface. I'll keep reading through the manual. Let me know if you have any other ideas

Seems there are multiple pumps...as I may be wrong, here is my source:

https://tools.thermofisher.com/content/ ... 551-EN.pdf

Now I look again, I may be mistaken...manual annd AS purging. As long as the purge valve is closed, you should be okay.

i'll keep reading on this end too.

I have had that same problem on our Ultimate 3000. I don't use it often so I always start from scratch when ever I have to use it. From what I remember, Chromeleon would say that it was on and ready to pump but the pump wouldn't turn on. If I remember correctly it was an error condition in the pump that wasn't communicating back to the software.
I cycled the power and it reset. It required shutting it off at the back, not the front panel.

I started removing capillaries to see if there was any flow in any parts of the system. It went as far as the outlet capillary from the pulse damper, which feeds the inline filter. Nothing came out the other end of the inline filter, so I'm going to assume I need to replace the inline filter. Thanks to everyone for all the suggestions!

Best wishes 1510NF. I hope it is the filter, not bad to repair.