Chromatography Forum

I have a varian CP3800 GC with varian saturn 2000.
I am having trouble injecting my samples using the autosampler.
The syringe will go over to my sample vial and return to the home position and the system thinks it has injected my sample but it hasn't. I haven't changed any parameters on the method since the last time it injected the sample.
Has anybody else had this problem, if so how can I fix it.

Hi aman,
I have same set-up as you. Assuming that you have the liquid Chrompack add-on auto-injector (C8400?)
I have not had this particular problem though.
Have you changed to using different vials recently?
I would initially try turning the autosampler power off and on again.
If this does not work then you could try re-calibrating the syringe.
This is described in the manual - it may be one of several calibration settings is out.
I don't have the manual to hand but there are a few (ie position over vial, position over injector nut etc.).
It may well be the position over the vial that needs calibrating since the sensor may not be detecting the vial when it swings over.
Hope this helps.
WK

The problem is a reoccurring problem. I have previously tried calibrating the needle position and it has fixed the problem, however, it just happens again. I have recalibrated again, and it has fixed the problem, but for how long? I was just curious to see whether anybody else had come across this problem and whether it was a common fault with these types of autosamplers.
I spoke to a service engineer and he said a calibration would not solve the problem, however it seems to temporarily fix the problem.
Thanks for your reply.
Aman