Thermo Scientific ISQ, User Manual

Page: 136 / 152

8
Troubleshooting
Investigating Results Issues
114 ISQ User Guide Thermo Scientific
Poor Sensitivity With increased
retention time Carrier gas flow rate is too
low Increase the carrier gas flow rate.
Locate and remove possible obstructions
in the carrier gas line.
Check the septum for leaks.
Check the injector/column ferrules for
leaks.
With normal
retention time GC carrier gas line has leaks Run a leak test and correct leaks.
Syringe is leaking during
injection Replace syringe or piston seals, if
necessary.
Split injection temperature
is too low Increase the temperature of the injector.
Voltage is not reaching the
lens. Replace the lens plate and springs if
damaged.
Remove debris or broken pieces in the
manifold.
Run a lens check diagnostic.
Check the connection by removing or
inserting the ion source.
Retention Times Low reproducibility DCC is drifting or unstable Monitor the column pressure or flow.
Check and replace the controller, if
necessary.
Injection technique is
inadequate Pick injection technique suitable for the
injector and liner you are using.
Vaporization size of sample
inject larger than volume of
liner Reduce the injected amount and/or
volume.
Handshaking is not
configured correctly Be sure the GC is inhibited by the MS
and waits for contact closure by the
autosampler.
Column temperature is
unstable Check the main oven door and cooling
flap.
Monitor the column temperature.
Table 4. Troubleshooting Results Issues in Your Data, continued (Sheet 2 of 2)
Behavior Characteristic Cause Remedy