Agilent Technologies G6600-90006 - Manual (Page 98)

98 Operation and Maintenance Manual
Tube Replacement for the SCD
The Burner has two combustion tubes that require replacement: the upper
ceramic tube and the Large Ceramic Tube. Generally the tubes should be
replaced only if sensitivity decreases. The “Troubleshooting” chapter provides
additional information to assist in determining whether tube replacement may
be necessary. Refer to
Figure 1 on page 26 for proper part nomenclature.
Follow the instructions below for tube replacement.
1 Turn off power to the GC and the Controller and let the system cool down
under vacuum.
2 Turn off power to the vacuum pump.
3 Lift the Burner out of the shroud. It is recommended to remove the coil,
noting the position of the ferrule. In some instances, if the coil can be
uncoiled, it may be convenient to leave it attached to the Burner.
4 Disconnect the hydrogen and oxidant lines.
5 Disconnect the power connector that leads to the GC, if necessary.
6 Tilt the Burner at an angle, so that when loosening the union fitting the
upper ceramic tube does not slide down into the large ceramic tube.
7 Loosen and disconnect the union fitting, and pull the splitter fitting and
upper ceramic tube out of the Burner.
8 Slide the upper ceramic tube out of the splitter fitting.
9 Slide the upper ceramic tube into the splitter fitting, so that approximately
4 mm of the tube extends beyond the top of the fitting. Then, slide the
double taper ferrule onto the tube (see
Figure 37 and Figure 38 for proper
positioning). Gently holding these parts so that neither the ferrule nor the
upper ceramic tube slip out of position, finger-tighten the union fitting onto
the splitter fitting.
Figure 37 Orientation of the Double Taper Ferrule