Chromatography Forum

i was doing regular PM on my 6890 GC with dual ecd and noticed that a 2" piece of column was broken off inside the detector... i loosened the swage nut and dropped the MUG adaptor out of the detector and that is when my gas line broke right at the body of the adaptor... NUTS!!
i overnighted a new adaptor and replaced it... Leak checked it per literature fixed any leaks and retested...
restored operating conditions and the counts dropped from 840k to 90k pretty fast, it was then that i noticed that the vent line was still stoppered from the leak check so i unstoppered it and reattached the hose that vents it to our air handling system, counts have jumped to 200k and as i write this are slowly creeping past 250k...
what the heck is happening?
why does this happen on the same week the boss gets PT's.
any discussion is appreiciated.

Thankyou

casey

Have you tried baking out the detector. Also cranking up the make up flow might help sweep any contaminants out of the cell.

Any time you fill the detector with air like that you're going to get that response. Set it to high flow (like 120 mL make up) and bake it out at 300--but do this after being sure you have no more leaks. Sometimes the ferrule on the make up gas adapter needs a slight snugging, nothing much though don't over tighten. Give it a couple hours to bake out.

Agilent said the ecd was fryed... got a refurbished one installed and think it's doing okay... the old one crept up to 850K and stayed there...
FYI before you hook up the gas to a newly installed detector turn on the gc and zero the anode purge and make up gas flows... turn it off and then hook up the gas lines...
big ol headache if you don't.