Lost Prime

[Apple_insci]

I am getting a "lost prime" message with our Waters Alliance 2690 HPLC system. There is no mobile phase coming out in dry prime. I am new to trouble shooting. Has anybody else experienced this problem and if so would you please tell me how to solve it? Thanks!

[michaelcarolus]

Hi

We've had similar problems with our 2690's, especially with ACN as mobile phase. An easy way of getting the flow back is by cleaning your check valves. We normally clean our check valves by sonnicating it in MEOH for about 10 min.

Hope this helps.
Mike

[Apple_insci]

It did work!!!

Thank you very much!

[michaelcarolus]

Hi

This is normally a quick solution and works in most cases. If it does not solve the problem then you might need to change your check valves. Waters makes a "performance check valve" which I believe is better than the normal check valve. Try this, one of the suggestions will solve your probelm.

Cheers
Mike