3 Replies Latest reply on Jul 20, 2018 12:08 PM by james_jenkins

    Injection port problem on upgraded GCD


      I have inherited an upgraded HP GCD, basically a 5890 with some electronic controls and an MSD detector. The problem I'm having is that it acts as if I am doing a splitless injection, in that the solvent peak tails on for something like 6 minutes. This happens even at high split ratios (>100:1). I have 5890s that perform beautifully. Perhaps there is a setting in the parameters that needs fixed? Also, even though I have detector B set at 250-280 C, it says the MS temp is only about 20 C; could that be a problem? This instrument is critical in an important project. Thanks.

        • Re: Injection port problem on upgraded GCD

          Hi memfarmer,

          It sounds like you have a couple of issues here. The transfer line should be heating the MSD to more than 20 C, actually, even with the temp on the transfer line off, 20C would be unusual. It could be that the MSD is hot and there is a problem with that temp sensor. The solvent peak tailing sounds like a problem with a restricted or clogged split vent line , or a problem with the split valve itself. You would still be able to measure flow out the total flow port on the front even if the line was blocked.


          Unfortunately , both the GCD and 5890 are out of support with Agilent due to the age of the instrument (GCD introduced in Feb 1994 and end of guaranteed support for the G1800C was April of 2004).



            • Re: Injection port problem on upgraded GCD

              James: Thanks for the response. We now believe the problem could entirely be the lack of heat at the MS inlet. Detector B certainly works. But I gather that the transfer line heater is distinct from that. Where in the software (or hardware) do I turn it on, or is it automatically on? Thanks.


              Also, I damaged the signal cable (05971060416) and will be ordering one from a third party supplier.

              Chuck Garner

              Univ of Memphis