13 of 20
Jun 2001
Inlets
Agilent 6890 Gas Chromatograph Service Manual
Purged/Packed Inlet 220
Leak testing—EPC and manual inlets
5. Note the “Actual” reading on the display and monitor the pressure for
10 minutes.
You can use the stopwatch feature of the 6890 GC to monitor the time.
Press
[Time] and then [Enter] to start timing, then toggle between
the time and the pressure reading with the
[Time] and the [Front
Inlet
]/[Back Inlet] keys.
• If there is less than 0.7 psi pressure loss (0.07 psi/min.), consider
the system leak tight.
• If pressure loss is much greater than 0.7 psi, there is a leak that must
be found and corrected. See Correcting leaks later in this section.
6. When the system is considered leak tight, the caps may be removed, the
column reinstalled, its dimensions configured at keyboard, and the
desired pressure or flow rate set.