Thermo Scientific DSQ II, Hardware Manual

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3
Troubleshooting
Heated Zone Symptoms
132 DSQ II Hardware Manual Thermo Scientific
Heated Zone Symptoms
The ion source and transfer line are heated zones related to the DSQ II. The ion source heater
is controlled by the DSQ II and the transfer line heater is controlled by the Aux1 heated zone
of the TRACE GC Ultra or FOCUS GC.
Often, a heated zone problem is the result of downloading a method to the DSQ II that has a
different setpoint from the current setting, which causes a delay while the heated zone heats or
cools.
Component failures are less common, but can occur. These are usually related to open circuits
in heater cartridges or faulty temperature sensors. Refer to the GC documentation for
information about heated zones.
Excessive chromatographic peak tailing.
Possible Solutions
• Pressure check the inlet to see if there is a leak by pressurizing a sealed inlet to 250 kPa. If
there is no leak, the pressure in the inlet will not fall more than < 10 kPa within the first
minute. You can check the calibration of the K-factor by inserting the calibration column
and making sure the K-factor readback is 1. If the K-factor calibration is okay, put the
analytical column in and recheck the K-factor.
• The GC oven is not ramped to high enough temperature. Extend upper oven
temperature.
• The GC column needs to be replaced or does not have the appropriate stationary phase
for your application. Change GC column.
• The GC column does not extend 1 mm past the end of the transfer line tip. Insert the GC
column in transfer line so it extends 1 mm past the end of the tip. If the end of the
column is inside the tip, an excessive amount of GC effluent will contact the inside wall
of the tip.
• Ion source and/or transfer line are not hot enough. Increase the transfer line temperature.
It should be at least as hot as the highest GC oven temperature. Then try increasing the
ion source temperature.
• Sample analyte is absorbing in the GC injector. Clean and deactivate the injection liner.
You can also try liners made of different materials.