Chromatography Forum

Hello,
I've been having trouble with my Agilent 7890 system which is undergoing something called a "thermal shutdown". The only way to fix the instrument is to restart it, however within a few runs of doing so another "thermal shutdown" just ends up occurring. The "thermal shutdowns" occur at random. Sometimes the instrument works overnight while sometimes only for an hour before undergoing a "thermal shutdown".
Any thoughts?

A thermal shutdown can be caused by any of the heated zones in the 7890. You need to find out which zone is causing the problem. When this happens, the display should give you an indication of which heated zone is causing the problem. Once you know this, you can start troubleshooting. Problems are usually bad sensors or heaters.

Gasman

Thanks Gasman.
Unfortunately every time the instrument performs a "thermal shutdown" that's all it says on the screen. I've tried looking at the status screens to figure out which heated zone was the problem but I have been unable to figure it out. All of the heated zones are also turned off during the thermal shutdown. Is there a certain screen I must call up to see which heated zone is the problem?
Thanks again.

Hi
chances are its either inlet, detector or oven, trying 'running' your method without one switched on.

Thanks LCBob. The only problem with that, is that my instrument does not do a thermal shutdown every time I run a method. Yesterday it performed a thermal shutdown twice on me but I was also able to get about 8 runs in where it did not and everything ran just fine.

Have you checked the software logbook? Usually there will be more information in there. It should indicate which specific endpoint is not being met that is leading to the shutdown.

Kverge, I've checked the log file on the software and it only says that the system was "unable to connect to the remote server". I'm assuming that after the instrument has undergone a thermal shutdown the computer and instrument are unable to communicate. No errors actually appear in the log file.

Thermal Shutdown is result of failure of heating coil which supprot column oven to rise the temperature.
This phenomena is more common is GC which are operated at high temperature (HT Simdis, ASTM D7169). The correction task is very simple just open the heater coil generally covered with ceramic insulatots at supply end. As its coil just streach little and fixed it to suply and again restart the instrument.

Best Regards,

Niraj Trivedi