Chromatography Forum

Hi,

I recently found that the seal pack from my 2695 separation module is leaking. The seal pack rebuilt kit has not arrived yet.

I was reading the 2695 manual and got a few questions.

1. Is it okay to rebuild the seal pack first, and replace the needle after that? Maybe I got confused between needle replacement and reinstalling needle, but from the Waters video, seems that reinstalling the needle looks the same as needle replacement in the first part (aligning the needle, placing the needle into the needle tee etcs). I thought that it would be okay to rebuild the seal pack first, and replace the needle right after... Could anyone correct me if I am wrong?

2.To perform the compression check. Should I use a pin plug or column cap to tighten the column outlet to generate a back pressure upto 500psi, or just let the column outlet open and collect the solvent into a reservior?

Questions look stupid but I would really appreciate if anyone can answer me patiently. Thanks a lot!

Hyuna

Yes, installing the needle would be the same procedure whether it's the same needle or a new one. A lot of the time and effort of rebuilding the seal pack is taking the assembly out and putting it back, so re-installing the same needle and then replacing it shortly thereafter would be a lot of extra hassle.

Hi,

1. Perfectly okay to rebuild the seal pack and then insert the needle. Need the ensure the new needle is seated correctly or you'll create a void.

2. A column or restrictor is okay to use. Ensure you pressurise the system up too at least 4000psi to bed in the seals for ten minutes.

Regards,
Bull76

Hey Guys,

Thanks a lot for the advises and the new seal pack is working perfectly okay after the replacement 2 weeks ago. I didn't follow the instruction as I thought it would cause too much hassle. I was glad that you guys had the same thought as me and I didn't really mess up my second maintenance.

Cheers,

Hyuna