Varian 4000 GCMS, Installation Procedures Manual

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Figure 2.9
2.4 System Conditioning
Ensure that the Trap and Source (
external mode only
) temperatures are at
least 150 °C and the Manifold temperature is at least 50 °C before heating up the
transfer line, GC column oven, and injector so column stationary phase does not
collect on low temperature MS components. Condition the injector at 230 °C with
a high split ratio (e.g., 50:1 or 100:1). Condition the column starting at 50 °C,
ramping at 5 degrees/minute up to 300 °C (or a temperature appropriate for the
column stationary phase), and hold for 60 minutes.
From the Analysis tab on the Temperatures page set the Trap to 150 °C,
Manifold to 40 °C, Transfer Line to 230 °C, and the Source to 150 °C (
external
mode only
). These MS Analysis temperatures will be restored after the bakeout
period and are appropriate for the injections associated with an installation. Click
the Bakeout tab and enter temperatures of 220 °C for the Trap, 110 °C for the
Manifold, 250 °C for the Transfer Line, and 200 °C for the Source (
external
mode only
). Set a Hold Time that allows the bakeout to end about 2 hours
before arriving the next day and click on
Start Bakeout
. Be sure to leave System
Control open. If you do not, the bakeout will be cancelled.