Agilent Technologies 5975T LTM GC/MSD, Troubleshooting And Maintenance Manual

Page: 36 / 270

36 Troubleshooting and Maintenance Guide
3
Chromatographic Symptoms
Peak Areas Not Repeatable
Check the ALS syringe operation. (See the Troubleshooting
section of the
7683 Automatic Liquid Sampler Installation,
Operation and Maintenance manual.)
• Replace the syringe.
• Check for leaks in the inlet, liner (as applicable), and
column connection. (See
“Checking for Leaks” on page 99.)
• Check sample level in vials.
• Run replicates of known standards to verify the problem.
• Consider if this is the first run. (Has the instrument
stabilized?)
Poor repeatability
• Dirty syringe needle
• Dirty GC inlet
• Leaking GC inlet*
• Injection is too large
• Loose column connections
• Variations in pressure, column flow, and temperature
• Dirty ion source
• Loose connections in the analyzer
• Ground loops
* This could cause a fault condition in the GC that would prevent
the GC from operating.