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2
General Troubleshooting
Chromatographic Symptoms
These are symptoms you may observe in the chromatograms generated by data
acquisition. In general, these symptoms do not prevent you from operating your
GC/MS system. They indicate, however, that the data you are acquiring may not
be the best data obtainable. These symptoms can be caused by instrument
malfunctions, but are more likely caused by incorrect chromatographic
technique.
Two of the symptoms also apply to mass spectral data. (See
sensitivity"
No peaks
If an analysis shows no chromatographic peaks, only a flat baseline or minor
noise, run the automated tune program. If the MS passes tune, the problem is
most likely related to the GC. If the MS does not pass tune, the problem is most
likely in the MS.
Passes tune
•
•
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•
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•
Does not pass tune
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•
7250 Accurate-Mass Q-TOF Troubleshooting and Maintenance Manual
on page 32 and
Incorrect sample concentration
No analytes present
Syringe missing from the ALS or not installed correctly
Injection accidentally made in split mode instead of splitless mode
Empty or almost empty sample vial
Dirty GC inlet
Leaking GC inlet*
Loose column nut at the GC inlet*
* This could cause a fault condition in the GC that would prevent the GC
from operating.
Calibration vial is empty
Excessive foreline or analyzer chamber pressure
Very dirty ion source
Calibration valve is not working correctly
"Poor repeatability"
on page 33.)
"Poor
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Table of Contents
Troubleshooting
