Chromatography Agilent 7820
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It’s an Agilent 7820 chromatograph (with 3 FIDs). During maintenance, even when the valve operations were functioning normally, the chromatograph continued to switch valves irregularly as it processed samples. Has anyone encountered this issue and can help resolve it? Additionally, the ignition current value for the FIDs reached over 10W
When the valve events are functioning properly, the valves still switch irregularly as the chromatography system processes the sample; such irregular switching is likely due to an issue with the valve event settings, or there may be a leak in the solenoid valve itself. Moreover, the ignition current value of the FID reaches 10W+, and a too-high FID baseline is usually caused by a dirty collector.
The valve switches irregularly; there are issues with the valve event settings. It is possible to test the valve switching separately to determine whether it is working properly. There may also be air leakage in the solenoid valve, which can be checked using a leak detection fluid. The ignition current value of the FID reaches 10W; a high FID baseline is usually caused by dirt on the collector. Another possibility is that the carrier gas was not replaced according to the standards, resulting in abnormal carrier gas flow rates. The issue will be resolved if the exhaust time is increased.