Agilent Technologies 7000 Triple Quadrupole GC/MS, Maintenance Manual

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General Troubleshooting
2
Troubleshooting and Maintenance Manual 39
Foreline pressure is too low
If the pressures you observe are below 20 mTorr, check for the following:
• Column (carrier gas) flow is too low
•
Column plugged or crushed by an overtightened nut
• Collision gas flows are too low
• Empty or insufficient carrier gas supply*
•
Bent or pinched carrier gas tubing*
• Foreline gauge is not working correctly
* This could create a fault condition in the GC that would prevent the GC
from operating.
Analyzer chamber pressure is too low
If the pressures you observe are below 1 × 10
-6
Torr, check for the following:
• Column (carrier gas) flow is too low
• Collision gas flows are too low
•
Column plugged or crushed by overtightened nut
• Empty or insufficient carrier gas supply*
• Bent or pinched carrier gas tubing*
* This could create a fault condition in the GC that would prevent the GC
from operating.