Chromatography Forum

How often do you clean your split/splitless inlet vent line trap? We have an Agilent 6890N/5975 GC/MS. On the GC maintenance schedule, it says we should clean the split/splitless inlet vent line trap monthly. How do we clean a trap? Is the instruction on the manual? How often do we need to replace the cartridge?

Thanks a lot!

Hi,
It depends on how often you use the instrument and how dirty your samples are. I normally clean split/splitless inlet vent trap every six month and replace the cartridge annually when I re-qualify the GC. I don't exactly remember but I do believe the instruction is in the manual. However, if you couldn't find it, you could get to the vent trap by removing the autosampler tray and all (don't forget to unplug the power cord). You will find an 1/8 inch copper line (vent trap) connect to the inlet and trace it to the end of the line, you will find the cartridge holder, which houses the cartridge. To clean the vent trap, you could rinse it with alcohol (I normally use acetone for faster drying before I re-install it). Pay attention to the color of the rinsate, if you see color, you could increase the cleaning frequency.
Have fun,

We clean ours at about yearly intervals. Normally however we take the entire port apart as well. Most of the crud that goes into the split line gets stuck right where it connects onto the injection port. If you dismantle the injection port you can soak the entire weldment in solvent (we use DMF). These weldments are available from Agilent so we keep a spare that has been cleaned ready to swap over to reduce down time.
Incidently is is not just extraneous sample that ends up down the split line, we have found bits of glass wool as well. We always replace the split line with new tubing, it is afterall standard Swagelock kit.

GCguy