Preventive Maintenance
Split/splitless capillary inlets
WARNING
Caution
Caution
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.
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.
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.
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