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- Posts: 20
- Joined: Thu Jun 20, 2019 2:10 pm
Instruments:
ATD= PE TurboMatrix 650
GC = PE Clarus 680
MS= PE SQ 8 T
Initial issue: High nitrogen in a/w check (~90% of mz 69). N2:O2 was typically about 5:1, but other ChromForum posts suggested this could still be an air leak, just the scrubber is removing some oxygen. Note: with MS capped, no leak is seen. Pic is with MS not capped: https://alleghenycounty-my.sharepoint.c ... w?e=lG5UX2
Initial Fix Attempts: I won't list everything, but basically I did everything I could think of/read online about 3 times. Multiple people leak checked everything multiple times with leak detector and canned air. Replaced/tightened connections over and over, changed tanks, everything. PE applications specialist suggested many things to try, none of which worked. Were due for PMs on all three instruments anyway, so service call was made.
Service Call Actions (performed by/with engineer):
ATD: failing "column leak test"--> tightened all ATD connections --> column leak test passed consistently;
-Replaced o-rings and filter in sample tube holding assembly--> tube leak check passes consistently.
MS: Capped MS, confirmed a/w check is decent with cap;
-Changed pump oil;
-cleaned source (I had cleaned it about two weeks prior);
-filled ref gas vial and flushed valve lines for air;
-reinstalled the column into the MS with a fresh cut and fittings. Here's where the fun starts...
Resulting A/W check (see pic): (In addition to there still being high nitrogen) Lots of noise around all masses checked. Neither Autotune or mass calibration will complete. We receive this error: "Unable to set appropriate values for low/high mass resolution". https://alleghenycounty-my.sharepoint.c ... g?e=xYsJnL
Service Call Fix Attempts: vented, reassembled the source--> no change;
-pumped down overnight (it was the end of the day) and ordered some parts;
-the service engineer replaced the high energy power supply--> no change;
-replaced the head amp board--> no change;
-replaced the EM--> no change.
End Result: The engineer had to move onto another customer and is sending a main board for another engineer to replace.
Has anyone experienced anything like this? Any ideas of what could cause this to randomly happen after super routine maintenance (performed by a service engineer to boot!)? Help, please!!