This Information Applies To: Agilent GC Systems with thermal conductivity detector (TCD)
Baking the thermal conductivity detector (TCD) at high temperatures can remove sample contaminants that have deposited on the detector surfaces.
Steps to follow
Caution: If the column is not installed, you must turn off the TCD filament and cap the detector column fitting to prevent irreparable damage to the filament caused by oxygen entering the detector.
Note the value of the FID signal output for comparison with value after the bake-out.
Determine if you need to remove the column. The detector bake-out temperature is 375 °C and the column temperature is 250 or 25 °C above the normal maximum operating temperature. If the upper temperature for the column is less than the bake-out temperature, remove the column, otherwise, jump directly to step 4:
Warning: If using hydrogen as a carrier gas, turn off the hydrogen supply and remove the column to prevent an oven explosion.
Set the temperature zones to the bake out temperatures:
Caution: Do not exceed the column manufacturer's recommended temperature, as it will damage the column. If the bake out temperature exceeds the recommended temperature, remove the column and turn off the inlet gas flows.
Set the detector temperature to 350 to 375 °C, or 25 °C higher than the normal operating temperature
Set the oven temperature to 250 or 25 °C above the normal maximum operating temperature. Do not exceed the inlet temperature.
Hold at the bake out temperature for several hours
Allow the instrument to cool and reinstall the column if appropriate.
Load the normal analytical method and allow the system to equilibrate.
Check the TCD output value. It should be lower than the first reading. Without a column installed, a clean system baseline should be < 20 pA. If it is not, contact your Agilent service center.
Learn how to effectively operate your Agilent GC Detector: