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

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Chromatographic Symptoms
3
Troubleshooting and Maintenance Guide 45
Peak Tailing
The figure below shows an example of tailing peaks. When
troubleshooting tailing peaks, consider:
• Which peaks are tailing?
• Are the tailing peaks active compounds, all compounds, or
are there trends (such as early eluters or late eluters)?
• Check the column for severe contamination.
• Consider the column stationary phase (active column).
• Verify that the column was cut and installed properly.
• Consider the type of adapter, liner, and inlet seal being used.
One or all of these may be contaminated or active.
• Check adapters (if installed) and liner for solid particles.
• For splitless injection, consider compatibility between the
solvent and column.
• Verify that the injection technique is adequate.
• Verify the inlet temperature.
• Check for dead volume in the system. Check for correct
column installation at both ends.
• Inspect any transfer lines for cold spots.
Peaks are tailing
• Active sites in the sample path
• Injection is too large
• Incorrect GC inlet temperature
• Insufficient column flow
• GC/MSD interface temperature is too low
• Ion source temperature is too low