Micromeritics Gemini VII 2390a, Operator'S Manual

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Preventive Maintenance Gemini VII
9-6 239-42828-01 - Dec 2012
5. Rinse the Dewar with warm water to melt any ice accumulation which may remain in the Dewar,
then dry thoroughly.
Replacing Port Filter (Frit) and O-ring
A filter (frit) is located in each analysis port. If the filter is contaminated, the contaminant may adsorb
or desorb during analysis, affecting the results. A contaminated filter on the analysis port may be indi-
cated as a leak or a free space reading much lower than normal.
A contaminated filter should be replaced as follows:
1. Select
Unit [n] > Show Instrument Schematic
, then
Unit [n] > Enable Manual Control.
2. Right-click on the valve of the appropriate port and select
Close
to close the valve.
3. Use a wrench to remove the sample tube fitting from the port. Pry out the filter and O-ring.
4. Replace the filter and O-ring. Carefully reassemble the sample tube fitting and reinstall on the
sample port. Tighten by hand, then with a wrench to prevent leaks.
O-ring
Sample tube fitting
Filter (frit)
To avoid degassing problems, the filter and O-ring should be clean and should not be
touched with bare hands.