Chromatography Forum

Hi professionals.
My question is very general. Do pump check valves need to be sonicated or just flushed by using syringe.
Few service engineers suggest me to sonicate few suggest to flush with syringe.
Please help me in this regard.

Both, as long as it works. I generally flush 1st (Water, Methanol, Acetonitrile, IPA, Hexane..) with the column offline. If that doesn't work I extract and sonicate (after a visual examination).

If you are using ruby/sapphire check valves and pumping straight ACN, you can avoid the need for flushing/sonicating by switching to ceramic.

Thank you sir. But I am using ruby check valves how can I identify when the life time of it is completed.

When they are scratched, warped, full of gunk.

...or annually, as part of a routine PM service (more frequently if the system is used lots or problems come up regularly between PMs).

you can remove the check valve and hold them up to your ear while shaking it.
If its good, you will hear the tiny ruby ball make a rattling sound ( the ball going up and down)
If you do not hear this sound, it is stuck and should be sonicated in IPA or meoh.
Of course, when you have consistent pressure fluctuations from your trace- the main culprit is check valves, then pump seals.

Thank you sir. This will help me alot in troubleshooting