Chromatography Forum

Hi!
First time poster, and quite the LCMS noob over here.
I'm currently working on an LCMS system with a CTO-20AC column oven that is giving me issues.

Recently every time I try to start a run, or turn the column oven on, it will stop and tell me there is a leak sensor problem (ERR LEAK DETECTED). Since there is no liquid leak from the column, I did some internet looking up and I'm guessing it's the vapor sensor that is having the problem, but I'm not sure how to fix this problem. I've also noticed tha if I disconnect my guard column, the leak error stops.

Any helpful suggestions out there I can try before I am forced into calling technical support and have them laugh in my face when it turns out the fix is quite easy? Any tips would be appreciated. Thanks!

the fix is quite easy

Replace the guard column (if it's a cartridge type, perhaps replace the holder as well).

Thanks for the tip Tom!

I've replaced the column, and since the issue is still there I'll replace the holder (as soon as I get another one sent in...)

Why does the holder need replacement as well? Is it caused by blockage or something that I might be able to clean out while I wait for my replacement holder to arrive? If not, I'll just have to hope that my next samples won't be too bad or try to wait to run those...

You stated that the error did not occur when the guard was removed, so the leak has to come from either the cartridge or the holder. If swapping out the cartridge doesn't fix the problem, then it's the holder. You didn't say whose system you're using, but on many of them, the cartridge seal is actually incorporated into the holder not the cartridge (much like the seals on the pump are part of the head, not the piston).