To Perform A Coc Pressure Decay Leak Test; To Perform A Coc Pressure Decay Test - Agilent Technologies 7890 Series Troubleshooting Manual

7
Checking for Leaks

To Perform a COC Pressure Decay Leak Test

To Perform a COC Pressure Decay Test

156
Use the Agilent Instrument Utilities Cool On-Column Inlet
Pressure Decay Test to determine if the inlet is leaking. Open
the software, select the GC, and run the test for the inlet.
If the Instrument Utilities software is not available, see the
procedure below.
If the test fails:
• Use an electronic leak detector to check the connections to
the flow module. Tighten connections or replace O-rings as
needed.
• Check the flow module for leaks.
• Use an electronic leak detector to check the tubing between
the inlet body and the flow module for leaks.
• Check the plugged column fitting and the septum purge cap.
• Tighten the septum nut.
• Replace the septum if necessary.
The pressure decay test checks for leaks from the inlet flow
module up to the column fitting.
After performing maintenance, first check for leaks in
externally accessible areas. See
If a leak is known to exist, check the externally accessible inlet
fittings first, especially any connection that has seen recent
maintenance, such as the septum nut, column adapter, column
connection, and so forth. See
The pressure decay leak test described below requires removing
the column and capping the inlet column fitting. This test
can/cannot find the following types of leaks:
"To Check for External
"To Check for External
Agilent 7890 Series Troubleshooting
Leaks".
Leaks".