1

Press the [SYSTEM] key on the GC unit and select "INJ Maintenance" in the PF menu.

The temperature of the sample injection port and the column oven will lower automatically, and the supply of carrier gas will stop when it goes below 50 deg.C.

2

Check that the message "Perform INJ maintenance" appears on the GC display.

3

Loosen and remove the septum nut.

4

Remove the needle guide.

5

Remove the septum.

6

Type of septum

White 201-35584 (Standard type, 20 pieces)

Blue 221-48972-91 (LL long-life, 20 pieces)

Brown 221-48398-91 (HT for high temperatures, 20 pieces)

Green 221-35507-01 (Thermogreen LB-2, 20 pieces)

7

Replace the septum.

8

Put back the needle guide.

9

Tighten the septum nut fully, and then loosen it half a turn.

10

(Press the [SYSTEM] key) Select "Analysis" in the PF menu. The GC will be readied automatically.

11

Select "3. Analysis Counter" on the screen in which the [DIAG] key is pressed. Place the cursor on "Counter for Septum" and select "Reset" in the PF menu to reset the analysis count.

Hint:

The type of bleeding experienced varies with each septum type, and appear as different patterns on the chromatogram. When conducting high sensitivity analysis, a septum which does not exhibit bleeding in a position that would obstruct the peak of the target compound needs to be chosen. In addition, performing conditioning for a few hours at about 120 deg.C to 150 deg.C (up to about 200 deg.C for the LL, HT septums) after extraction with hexane for a few hours may reduce bleeding.