Poor Sensitivity Or Sudden Loss In Sensitivity; Poor High Mass Response; Poor Sensitivity In Ci Mode - Thermo Scientific TSQ 8000 Evo Hardware Manual

2
Troubleshooting
Investigating Sensitivity Issues

Poor sensitivity or sudden loss in sensitivity.

Table 29. Possible Remedies for Poor Sensitivity or Sudden Loss is Sensitivity
Tune the system.
Check the system for air leaks and address them.
Make sure the ion volume is properly positioned. See
maintenance on your ion source, remove the ion source, verify that it is assembled correctly, and reinsert it into the TSQ 8000 Evo.
Make sure the GC column does not extend into the ion source. Use the column measuring tool to ensure the column is the correct length.
Make sure the GC column did not break inside the ion source. If necessary, remove the pieces from the ion source.
Clean or replace the GC injection port liner to remove possible contamination, trim the injector end of the column, or replace the septum.
Make sure the source magnets are positioned so that their south poles are facing up. Reposition them, if necessary.
Clean the ion source and lenses. See
Make sure the right type of ion volume is installed. EI and CI require different ion volumes and cannot be used interchangeably.
Check the electron multiplier gain and make sure it is not too low. Retune the detector gain. Replace the electron multiplier, if necessary.
See Replacing the Electron Multiplier

Poor high mass response.

Table 30. Possible Remedies for Poor High Mass Response
Run a resolution tune to make sure the resolution is set correctly.
Clean the ion volume and lenses. See
Reduce the ion source temperature to reduce the amount of thermal decomposition and fragmentation of your analyte.
Check the system for air leaks and address them. See

Poor sensitivity in CI mode.

Table 31. Possible Remedies for Poor Sensitivity in CI Mode
Make sure a CI ion volume is installed.
Make sure the electron entrance hole on the CI ion volume is clean. Use a sharpened wooden dowel to clean the hole. See
Durable Components for more information.
Remove the ion volume and check if the ion burn is centered around the small electron entrance hole. Be sure the filament is properly
inserted into the connector. Carefully bend the filament wire to better align it with the ion volume.
While running the instrument, you can push on the ion volume with the source exchange tool. Be sure to monitor the pressure to ensure
that you get a good seal around the tool. Otherwise, you may damage the filament. An increase in signal for the calibration gas as you
push on the ion volume usually indicates that the filament is not aligned properly.
98 TSQ 8000 Evo Hardware Manual
Reinserting the Ion Source Cartridge
Cleaning Durable Components
for details.
Cleaning Durable Components
Investigating Vacuum Issues
for details. If you recently performed
for details.
for details.
for details.
Cleaning
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