Micromeritics GEMINI VII, Operator'S Manual

Page: 188 / 253

10 Troubleshooting
Action B: Replace gas cylinder. See Replace a Gas Cylinder on page 10 - 11 .
Cause C: Undetermined.
Action C: Do the following:
1. Perform an empty tube analysis. See Perform a Leak Test on
page 10 - 15 and print the results.
2. Perform a reference material analysis. See Perform a Reference
Material Analysis on page 5 - 16 . Print the results.
3. Contact your Micromeritics Service Representative.
Specified pressure not reached.
Cause A: Sample or balance tube not properly attached.
Action A: Reattach sample and balance tubes. Ensure both are securely attached to
ports. Replace O-rings if defective. See
Sample Tube O-ring Replacement
on page 10 - 25 .
Cause B: Leak in gas line.
Action B: Perform the Adsorptive and Helium Line tests to determine if a leak exists.
See
Diagnostics on page 8 - 1 .
Unable to reach a satisfactory vacuum.
Cause A: Vacuum pump oil level is low or needs to be changed.
Action A: Inspect the oil to see if it is low or needs changing.
Cause B: Vacuum pump is leaking.
Action B: Locate and repair the source of the leak or replace pump.
Cause C: Centering ring has become too flat and unable to hold a vacuum.
Action C: Check the centering ring at the pump intake port. Also check the centering
ring at the top of the oil vapor trap. Replace if necessary.
Nitrogen or helium drained from tank, or depleted in a short period of time.
Cause: Leak in the gas line connection.
Action: Perform the Adsorptive (or Helium) Line test to determine the location of the
leak. See
Diagnostics on page 8 - 1 .
Unit does not work when powered ON.
10 - 2
Gemini VII Operator Manual
239-42828-01 (Rev H ) — May 2021