Replacing The Gas Chromatographic Column - Thermo Scientific EA IsoLink IRMS System Operating Manual

CAUTION As the lifetime of the furnace heater is limited, do not heat it to higher temperatures
than necessary. Put it to a lower standby temperature, when not in use for several days, or turn it off
for longer idle times.
• To measure:
Type of analysis
Oxygen of organic samples
Oxygen of inorganic samples
Hydrogen of organic samples
Hydrogen of inorganic samples
Water (sample amount > 1 μL)
• To cool down the furnace:
If you do not want to perform any analysis for about one day (for example, over night), put the
instrument in stand-by condition, and set the oven temperature to 150 °C.
• If you do not want to perform any analysis for more than one week, put the instrument in
stand-by condition, cool down both furnaces and oven to ambient temperatures.
• If the pyrolysis unit has not been in use for a long time or if it was off, heat the column to a
temperature of 190
separation columns during baking out
• Always watch the background of the masses 28 and 40. If the values exceed those you were used to,
perform a leak test. A small leak will crack the ceramic tube, and after a while the glassy carbon
reactor, too.
• After around 400 measurements (depending on size and type of the samples) clean or replace the
graphite crucible as described in the
After cleaning the crucible may be used again. See also reactor maintenance.

Replacing the Gas Chromatographic Column

The instrument rarely requires the gas chromatographic column replacement, however, in case, operate
according to the following operating sequence.
Note To replace the GC column in the ramped GC oven, please refer to the Ramped GC Oven
Operating Manual.
 To replace the gas chromatographic column in the GC oven of the EA.
Material Required
Open end wrenches for the column fittings
1. Open the instrument right door and remove adsorption filters from their securing clips.
Note According to the instrument configuration, there can be one or two adsorption filters in
the detector compartment.
Thermo Scientific
o
C for at least 24 hours. Make sure to maintain a flow through both
"To clean/replace the graphite crucible,"
Suggested operating temperature
1325 °C - 1350 °C
1450 °C
1450 °C
1450 °C
1400 °C
EA IsoLink IRMS System for CNSOH Operating Manual
7
Maintenance
Current Maintenance Program
operating sequence.
127