Dear Istvan,
there is a modification at the needle valve seat ferrule.
Thermo use a ferrule with a bigger core inside (0,8 mm).
You can order it with the pn 1221460 GVF-ferrule for Needle valve id 0.8mm.

I replaced at our 3 Deltas all seat ferrules and was wondering about the 
bad performance.
Lower signal height;  bad Ref gas peaks (round at the beginning).
After a few mails to the support, we get the info about this modification.

I hope this helps.

Best wishes
Sven

Fórizs István schrieb:
> Dear Ulrich and others who helped us with advises,
>
> after all we have made the first measurements during the night. Now it 
> worked acceptable, although the peak height has not encreased (it is 
> about half than was before). But now the H3 factor is far better. 
> After the cleaning of the ion source the H3 factor varied between 16 
> and 24!!
> Yesterday it was between 6.3 and 6.4, and looked stable. Today it was 
> 6.15 and 6.05 (we have measured it two times), and looks stable.
>
> What we have found are:
>
> 1) One plate in the ion source was 90 degrees off. It is the closest 
> one to the ionization box, no. 02, and without wire connection (there 
> is a metal ring between this plate and the ionization box). When we 
> put it to the proper position we expected a significant encrease in 
> the peak height, but it did not happen. We do not understand why.
>
> 2) The connections of the high voltage cable (red) on the outer part 
> of the ion source were (and are) loose. Practically after may 
> disassembling and reassembling one of these connections was 
> disconnected. When we discovered it, we realized that all these 
> connections are loose a priori. So we have to be very careful when 
> cleaning the source.
>
> What we have not checked is the needle valve on the input port of the 
> MS. We have noticed that now it is more difficult (needs more force) 
> to close and open it then before. May be that it causes the half 
> height peak?
> What is your experience with the needle valve?
>
> Thank you very much for the help provided by many of you!
>
> Best wishes
> Istvan
>
-- 
Sven Steinbrenner

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