Chapter 12
ECD Troubleshooting
Maintaining an Electron Capture Detector
Maintenance and Troubleshooting Manual
235
ECD Troubleshooting
Change in Sensitivity
Temperature
The effect of a temperature change on the ECD response generally depends on the
compounds analyzed.
Gases
The ECD behavior can be affected by a change of the total flow of the gases
through the cell. The resulting response is also related to the nature and purity of
the gases.
The gases normally used on the ECD are reported in Table 12-2
Table 12-2.
Gases used for ECD
Carrier gas
Make-up gas
Capillary Columns
Packed Columns
Helium
Nitrogen
Hydrogen
Nitrogen
Argon-Methane (5-10%)
Nitrogen (recommended)
Argon-Methane (5-10%)
When using helium or hydrogen as a carrier gas with capillary or wide bore
columns, the detector should be fed with nitrogen or argon/methane through the
make-up gas line.
The carrier gas flow rate must be set according to the type of the gas used and to
the diameter and the stationary phase of the capillary (or packed) column
installed.