Chapter 9
PTV Troubleshooting
Maintaining a PTV Injector
Maintenance and Troubleshooting Manual
171
PTV Troubleshooting
Sensitivity
Low sensitivity is commonly caused by incorrect operating conditions. It might
also be due to a dirty liner or to a liner wrong sized with regards to the volume of
the sample injected.
Lack of sensitivity for selected compounds can also be related to discrimination
phenomena induced by inadequate injection conditions.
Discrimination
Possible discrimination of the heavy or volatile fraction of the sample may be
caused by operating conditions set incorrectly with regard to the chosen injection
mode.
Discrimination could also be caused by:
•
degradation of the thermally labile compounds due to the cathalytic effect of
bad deactivated quartz wool inside the liner
•
by-products originated in previous injections that have been not completely
eliminated from the liner during the cleaning phase or the cleaning operating
sequence.
The
on page 172 reports a list of possible symptoms,
their probable causes and the suggested remedies when using a PTV injector.
Large Volume PTV
on page 176 will help you in troubleshooting a
PTV injector adapted for Large Volume injections.