Drop in N2 Flow Rate

Why don't you think it is NOT a problem with your source of Nitrogen gas ? The N generator is probably supplied by a source of air (such as an in-house air compressor) and if this drops in pressure so will the N output. Your N Generator also has cartridges which must be replaced and serviced on a routine schedule. Have you been keeping up with the maintenance on these ? If not, that is a second reason why output could be rolling off over time. There are other possibilities, but these are the two most common ones that I see.

Thank you to Bill Letter for providing this response to LabWrench

Please check the Nitrogen Generator and ensure you get required output from the N2 Generato.

Thank you to Venkatesaan J for providing this response to LabWrench

Having confirmed that it's not a problem with your compressor or nitrogen generator, I would check any inline filters. Agilent usually fit hydrocarbon filters on the nitrogen supply. These can suddenly or gradually block...happened to us with a brand new filter just after our annual service visit.

Thank you to Amin Mirza for providing this response to LabWrench

If your external n2 source, eg n2 generator is not giving enough pressure. You will have an error message. But if you do not observe any error messages and only see the n2 flow readbacks to be slowly dropping. You need to call for an Agilent engineer for help. There is a part that is not working well.

Thank you to Kelvin Ma for providing this response to LabWrench

I would also check the tubing to the source. We had a similar problem and found that the rubing was kinked. We changed out the kinked piece and it's been fine since.

Thank you to Cynthia Sanderson for providing this response to LabWrench

I'm sure that you've already done this however - it may be appropriate to recheck all Swagelock fittings, ferrules and connectors (generator/ moisture trap etc.) and make sure that they are properly set.

Thank you to Edward Daly for providing this response to LabWrench