Agilent Technologies 6890 Series Service Manual page 9

Contents
Leak testing.................................................................................................. 7
Potential leak points........................................................................... 7
Leak testing the tri-column assembly............................................... 7
Leak testing the SVE assembly.......................................................... 9
270 Pneumatics Control Module
Theory of operation.................................................................................... 1
Replacement procedures ........................................................................... 2
Replacing the PCM.............................................................................. 2
Replacing the PCM gang weldment .................................................. 4
Calibrating the PCM interface ........................................................... 5
Leak testing the PCM.................................................................................. 7
Forward pressure valve leaks ........................................................... 8
Locating leaks on the flow manifold ................................................ 8
Correcting leaks ................................................................................ 10
Potential leak areas .......................................................................... 10
300 Detectors
310 Flame Ionization Detector (FID)
Theory of operation.................................................................................... 1
EPC detector ....................................................................................... 1
Manually controlled detector ............................................................ 2
Replacement procedures ........................................................................... 4
Replacing the entire detector ............................................................ 4
Replacing the detector weldment ..................................................... 8
Replacing the collector assembly ..................................................... 9
Replacing the FID jet ........................................................................ 11
Removing the electrometer ............................................................. 13
Removing a flow manifold ............................................................... 14
Installing a manifold ......................................................................... 16
Removing the FID interface board ................................................. 20
Diagnostics ................................................................................................ 22
FID ignition problems ...................................................................... 22
6 of 24
Contents
Agilent 6890 Gas Chromatograph Service Manual
Jun 2001