5975 C. PFTBA peaks disappear. Valve clicks.

Have you checked the PFTBA level in the cal bulb? Sounds simple I know, but we get calls on this with empty cal vials.

It just happened again. After pump down completion the PFTBA peaks are visible and stable again. Other than a glitch I don't know how to explain the issue.

It may be worthwhile logging a service call and having a trained Agilent Representative look at the system. Seems signal related. How are your runs? Maybe a detector problem or HED issue, but just guessing based on the information. Nothing replaces feet on the ground in front of the instrument. Does the tune show a large number of peaks in the background? A scan of the tune report may help if you want to post it.

Peaks seem historically the same. Your statement makes sense. Thank you James. I'll share the tune report once I can get it scanned.

Good morning. I have and old issue. My PFTBA peaks are showing this noise as if the valve was closed when I do hear the opening click (it's also plugged in as it was before although I did pull the cable out and reinsert afterwards). MS status, I/O test and controller board shows "OK". Both filaments have current through them. After venting and pumping down (nothing done on unit) the peaks reappear for most of the day. I am uploading the latest autotuned report. Before calling service I need to assure this is not a minor event. Thank you.

Good morning. I have and old issue. My PFTBA peaks are showing this noise as if the valve was closed when I do hear the opening click (it's also plugged in as it was before although I did pull the cable out and reinsert afterwards). MS status, I/O test and controller board shows "OK". Both filaments have current through them. After venting and pumping down (nothing done on unit) the peaks reappear for most of the day. I am uploading the latest autotuned report. Before calling service I need to assure this is not a minor event. Thank you.