Chromatography Forum

I am considering a purchase of a new PTV injector for the Agilent 7890 instrument. I found 2 manufacturers of PTVs, which should be both suitable for this instrument. One PTV is directly offered by Agilent (I think originally produced by Gerstel) the other one is made by a company ASAP. I am interested in comparisons of those two systems or experiences with ASAP system with regard to liner availbility, exchange, easy of the column installation or any other feedback.
Thank you, AK

Is one of the injectors you are looking at the Agilent Mulit-Mode Inlet (MMI)? I thought they offered both ther Gerstel one and their MMI which is much more like the SSL injector but with programmable temperature and CO2/N2 cooling. I spec'd out a GC previously (but never purchased it) with the MMI inlet as Agilent said it was different than the Gerstel one. The benefit that I liked about it was that they told me that it basically disassembles like the old Agilent SSL injector and it uses the standard Agilent liners.

I admittedly know nothing about the other brand (ASAP). We have an old APEX LVI on a 6890 in the lab but it hasn't been used for about 5 years.

Liners avilability etc., is different in different countries. Nobody can advice on that (especially when we do not know which country You are in).

I would strongly advice against purchasing injector from producer who does not have representative in your country.

Gerstel is still offering their own PTV for Agilent GCs which is different from Agilent MMI inlet (even that it is manufactured by Gerstel factory). So it makes one more possible candidate. In some countries Gerstel sells trough Agilent representatives, in other countries they have separate bussines partner - You have to check. In Europe most PTVs I have encountered are from Gerstel.

I use a 7890 with the Gerstel PTV, any specific questions?

Physically, I have found it to be pretty nice. Reliable, liner is very easy to replace, column installation is pretty much the same as a S/SL injection port.

However, the software is not very good. It's very confusing as to what flow is going where. For the setup that I have at least, you control it using Chemstation, but using co-opted fields that are controlling different things than what they are labelled as...hard to explain, but I find it very poorly done in that regard.