Chromatography Forum

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5890 GC FID: ChemStation initialilizes, baseline begins at 8.4 million and does not deviate up or down. Same with running sample, no change. Inlet and Detector levels up to 250* and 330* respectively, normal range. Hydrogen at 15 psi, Compressed air at 45 psi. Of course, this happens during the Knoxville Nationals sprint car racing.
Is there an easy ‘fix’ or is it too involved?

WillieeBill66

It means FID collector is short circuit .
Dirt and rust accumulation may cause this.
Sometimes water droplets in the collector also gives the same problem , if the FID ignited when cold.

You need to disassemble the FID chimney , clean the parts , and reassemble it.

Agree - likely a short in the detector; take apart, clean and re-assemble correctly.

We had this happen on our 5830, 5840, 5890 (etc.) units, like same FID detectors.....

Thank you. I'll be sure and clean parts. $500,000+ up for grabs this evenings races.
Again, much appreciated.

If cleaning the jet doesn't work, you might have to find a replacement detector board. They are very easy to install. I had this problem with a Series II not long ago. Found a used detector board on Ebay for $50. Certainly worth the risk to save an instrument. Exchanged with with the old board and now it's working like a charm.

Just had a maintenance call on this problem on a 7890. All that was done was to swap out the collector body.

In the past, when cleaning the FID, I have never physically cleaned that part. I just put it in the beaker with my methanol and it was always enough. Had I run a cotton-tipped swab through it a few times before sonication and subsequent installation, it would have likely prevented a service call.

At this time, we are on our 'winter' break. Now I can focus on cleaning those items and do an overall check of the 5890. I have a 2-setting electronic air duster that I use on the low setting.

Thank you for your replies.