Preventive Maintenance
Split/splitless capillary inlets
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Split/splitless capillary inlets
Changing septa
For a conventional disk•typeseptum, lifetime is dependent upon needle
quality; needles should be sharply pointed and free of burrs or rough
surfaces.
Choice of septum material is less critical than with a packed column inlet
since the septum is continually purged. Thus, septa can be chosen
primarily for durability. Septa, 11 mm (Part No. 5181•1263,package of
25) are recommended.
Note that regardless of the material, septa must be clean and free of
particulate matter.
Exercise care! The oven and/or inlet or detector fittings may be hot
enough to cause burns.
WARNING
Caution
If operating in split mode, carrier gas pressure must be reduced before
opening the inlet. If not done, pressure may blow insert packing out of
the inlet, altering its characteristics.
Caution
Column flow is interrupted while changing septa; since capillary
columns may be damaged at elevated temperature without carrier flow,
cool the oven to ambient before proceeding.
