Baby, Light my fire... sorry, I mean “my FID”4 May 2010
FIDs are used in many applications. It’s a great sensitive detector that can also be easily maintained. Important for highest signal to noise is to optimize hydrogen and air flows. Some FID designs do also get some extra sensitivity when nitrogen is added. As signal must be stable, it is recommended to purify the hydrogen, air and nitrogen from organics, using a charcoal scrubber. Especially air coming from compressor can contain hydrocarbon impurities released by oils
Working last week in the lab with my 5890 – FID, I had optimized all the gas flows, but could not get the detector flame ignited. From the top, you could see the ignition glow but it just wouldn’t light.
My colleague Rick Morehead told me: you should ‘blow’ the detector.
First I thought he made a joke, but indeed, by gently blowing some air (breath) over the top of the FID, it ignited immediately.