ISQ User Guide - Write Frame of Mind

Troubleshooting
This section contains information to help you diagnose problems within your data. A lot of
times, your experience as a scientist will enable you to look at your data and detect that
something is wrong either with the instrument or your sample. This chapter describes the
most common indications of a problem with a baseline, peak or result.
As you review your data, you may notice issues with the baseline, peaks, or results. Use the
information in this section to troubleshoot and resolve the issue. If there is an issue with the
hardware, see the Troubleshooting section of the ISQ Hardware Manual.
WARNING - ELECTRICAL SHOCK HAZARD: When troubleshooting any issue that
requires removing a cover on the ISQ, you should power-off and vent the instrument to
avoid any harm to yourself.
A good first step for troubleshooting is to run a tune on the ISQ. If you have good ion
intensities, good peak shapes, and no air leak, you might want to look first at the GC,
autosampler, or carrier gas.
If you have an air leak, locate and address them. Pay particular attention to the transfer line
ferrule, vent valve knob, front panel, and vacuum interlock on the ISQ, as well as the inlet on
the GC.
If your intensities are too low, make sure carrier vacuum compensation is turned on.
If you have no ions:
• Switch filaments
• Confirm the starting tune file is appropriate for ionization mode or source cleanliness
level
• Confirm the correct ion volume is inserted (EI or CI)
• Run diagnostic checks (diagnostics only tune type)
• Clean the ion source
If you do not see ions in CI mode:
• Confirm that the CI ion volume is installed
• Confirm that the reagent gas is connected and turned on
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