Equipment used 7890A natural Gas GC with extended analysis. During operation, FID is frequently shut-off. Try to ignite manually and temporarily solve the problem. But what need to check for identifying the problem?
Find maintenance, best practice, and troubleshooting articles.
Equipment used 7890A natural Gas GC with extended analysis. During operation, FID is frequently shut-off. Try to ignite manually and temporarily solve the problem. But what need to check for identifying the problem?
I have updated the tags for better visibility of your post. Could you reply with the FID parameters that you are using? Temperature, flows etc? If there hasn't been any problems in the past, the most likely cause is that the jet needs to be changed.
James
Hello mdabdullahalmamun,
I attached a document that lists several things you can check on the FID when there are problems with the flame. A plugged jet could potentially be the problem, but it could also be a low detector temp or H2 or air flow.
You can check for a plugged jet in the following way:
Jet Restriction Diagnostic Test – Turn off Air and Makeup Gas and set the H2 flow to 75 (you may have to increase the H2 supply pressure). Monitor the Makeup Gas flow reading while turning the H2 flow off and on – it should remain very close to zero ml/min – if pressure builds up due to a plugged jet, the Makeup Gas flow reading will increase by >1 ml/minute.
Please see the attached problem statement and method parameters for better understanding. Let me know if additional data you need.
I would still focus on the FID, the PCM shut down and other shut downs could be related to hydrogen safety shut downs. Simple and quick would be to change the jet or in the very least run the test that apcharles suggested.
The signal value when lit was 10.7. I wouldn't recommend lowering lit offset to 0.1 as you could possibly have a flame out situation and the detector fuel gas would not turn off (Hydrogen). A lit offset of 2.0 is sufficient in most cases. If the signal is quiet you can go lower, but caution should be used.