By Anonymous on Wednesday, June 2, 2004 - 07:40 am:

Dear all,
I am a new user of LC/MS. I recently met a problem with our Finnigan TSQ 700 mass spectrometer. After a few hours running, the temperature of the heated capillary dropped to about 40 degree Celsius, which was set up 200 degree Celsius, and therefore vacuum was lost. After reset the MS system, it seems work fine, but the problem will happen again within a few hours. The instrument was operated at positive ESI mode. Anybody know what's wrong here?
Thanks!

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By dlorenzo on Wednesday, June 2, 2004 - 10:37 am:

It seems that you have a vacuum problem and then an autoshutdown started.
Are you in front of the ms to see any message on the PC?

How old is your Finnigan?

Thanks

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By Anonymous on Thursday, June 3, 2004 - 03:58 pm:

Hi,dlorenzo,
I set two test run yesterday, but that vacuum problem did not happen. What can I do about this randomly occurring problem? Our finnigan is 15 years old.
Thank you very much!

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By Rafael Chust on Monday, June 7, 2004 - 04:32 am:

Being a MS, you might use a quite simple method to find leaks. Put the system running and using a cloth embedded in methanol or acethone, pass it to every connection. If you see a peak in your MS, you have a leak!