User`s guide

Routine Maintenance
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careful not to pull the insert body too far since this may
damage the brazed tubes.
7. Install new o-rings and/or filter disk using tweezers or
forceps.
NOTE: Do not touch the filter disk with your fingers.
8. Reassemble the mobile seal and retighten the mobile
seal cap. Do not overtighten the mobile seal. tighten
only finger tight. Carefully insert the brazed tubes on the
insert body and do not bend them.
9. Reinstall the carousel.
10. Turn on the dry air gas supply.
Leak Testing
You must perform a leak test whenever you change the column or
transfer line. You may also want to perform a leak test at the system
at routine intervals to ensure system integrity.
The ATD/TD automatically performs a leak test on the sample tube
and the cold trap before starting the thermal desorption process.
Any leak in the system prior to the column is equivalent to an
uncontrolled split vent, and as such renders quantitation impossible.
As with any GC installation it is imperative to eliminate all leaks in
order to achieve optimum chromatography.
However, there are some parts of the system that are not included in
this test, in particular the column connections.
NOTE: You should try to perform the leak check while the system is
heated to operational temperatures.
It is strongly recommended that you perform a leak check on the
total system at routine intervals, and whenever the column or
transfer line is changed.
To test for leaks:
1. Disconnect the column from the GC detector and cap
the column. Fused silica columns can be capped by