Varian 450-GC, User Manual

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Maintenance
Varian, Inc. User Manual 450-GC Page: 431
The carrier gas should first pass through a hydrocarbon trap, then a moisture
filter and then an oxygen trap. As moisture reduces the effectiveness of an
oxygen trap, a moisture trap should always be placed in front of an oxygen trap.
The moisture trap should also be changed immediately when it changes color
to prevent breakthrough of moisture to the oxygen trap.
The minimum recommended carrier gas purifier configuration is a moisture and
hydrocarbon trap. This configuration can be used with routine GC analyses
using FID, TCD, TSD and PFPD detectors. If an ECD or mass spectrometer is
being used, an oxygen trap should also be added. For trace analysis the
combination of hydrocarbon trap, moisture trap and oxygen traps should be
used.
To install or replace the Gas Clean filter cartridges: remove new filter from
sealed bag. Unscrew the ring on the filter base, lift up the filter cartridge. Always
replace the 2 upper O-rings. The base contains check valves that shut off flow
when the cartridge is removed. Place ring over new cartridge, press and hold
cartridge to base and engage retaining ring.
The following are the gas purifiers available from Varian.
Check the Varian website for more information: www.varianinc.com.
Varian Gas Clean Filters Part Number
Gas Clean oxygen filter CP17970
Gas Clean charcoal filter CP17972
Gas Clean moisture filter CP17971
Gas Clean GC/MS filter CP17973
Table 63: Varian Gas Clean Filters