MS Ion Source and Quadrupole Heating Issues

[James_K]

Hello,

I have been doing some GC-MS work with a 6890N Agilent GC system linked to a 5973N MSD. For unknown reasons it looks like both the MS Ion Source and the MS Quadrupole have stopped being heated. As soon as I have set up the autosampler to run a sample, I get a message saying that the machine is waiting for MS temperatures to stabilize. The same window shows the setpoint temperatures in my method (230C for the MS source and 150C for the MS Quad), but the temperatures displayed in this window do not rise above 50 (MS Source) or 38 (MS Quad) no matter how long I wait with this window open. Has anyone experienced this problem before, or have any ideas about where I might start in trying to resolve this issue?

Thanks for your help.

- James

[MMJ88]

Hi James,

I had the same issue with my 5973N a while back. The source heater itself had broken. It is a small part that's not really listed online. You can order it if you know the part number though, which is G1099-60103.

Take out your ion source as if you're going to clean it (and hey, may as well clean it anyways). Reference:http://www.chem.agilent.com/en-US/Technical-Support/Instruments-Systems/Mass-Spectrometry/5973/IPB/PlusImages/A03808.jpg

Remove the repeller assembly from the ion source, then remove the source heater assembly from the repeller assembly. Reference:http://www.chem.agilent.com/en-US/Technical-Support/Instruments-Systems/Mass-Spectrometry/5973/IPB/PlusImages/A03809.jpg

There should be a little set screw that holds in the actual heater itself. It's just a little cylinder with two wires coming out of it (insulated with either green ceramic beads or a thermal cloth type fabric). I suspect that could be the culprit, the connection of the wires to the cylinder is pretty fragile.

I don't recall if this affected my mass filter heater (which heats the quad). Check the connections to that (similar to what I described) and the connections of the heaters to the board too. Pray it's not the board.

EDIT: If this description isn't clear enough, I'd be happy to correspond via email and try to help.

[Bigbear]

I've even had the set screw loosen so the heater can slide out. I doubt that it would heat evenly if loose.

[Yama001]

I had a similar problem where we all assumed it was the source heater or the board. I happenned to check things out one more time and found that the Hi-Vac cable was slightly loose.

[James_K]

Hi,

Thanks to everybody who helped out with this.

It turns out that the vacuum pump wasn't working because the fluid level had dropped too low, which probably would have been pretty obvious to anyone with more experience but I am new to this and didn't catch on. Looks like the pump had been leaking quite a bit of oil and the maintenance guys that regularly check the shared equipment somehow haven't been checking this..

[Erika.Miller]

Hello, I am replying to this post because I am having the same problem the OP was originally - my source and quad are not heating. But it seems that the final response to this thread, although from the same person, is resolving the issue of the vacuum not working, not the heater. My vacuum pump is working fine, and my ionization gauge is giving me a typical reading (10^-5). Is it that the high vacuum cable being loose will cause these two not to heat, or was this response meant to be left on another thread? I plan to vent my system today and check the set screw to see if it could be loose, I doubt anything is actually broken because we had some issues recently that led to the MS being vented and opened and, in my limited experience, it's far more likely that I screwed something up when I had it open than the heaters or board are actually broken. This did remind me that I need to change the oil in my vacuum pump when I vent later today, so thanks for that.

Thanks in advance for anyone who can answer my question...

Erika