Agilent Technologies 7820A

Agilent 7820 GC Service
133
Verify the following:
 Capillary column jet installed. If not, select and install a
capillary column jet.
 Capillary column adapter installed (adaptable FID only). If
not, install it.
 Chromatographic-grade gases plumbed and configured:
helium as carrier gas, nitrogen, hydrogen, and air.
(Nitrogen is an acceptable alternate carrier gas.)
 Empty waste vials loaded in sample turret.
 4-mL solvent vial with diffusion cap filled with isooctane
and inserted in Solvent A injector position.
Install the evaluation column. (See the procedure for the SS or
PP in the Maintenance manual.)
 Bake out the evaluation column for at least 30 min at
180 °C. (See the procedure for the SS or PP in the
Maintenance manual.)
 Be sure to configure the column.
Check the FID baseline output. The output should be between 5
pA and 20 pA and relatively stable. (If using a gas generator or
ultra pure gas, the signal may stabilize below 5 pA.) If the output
is outside this range or unstable, resolve this problem before
continuing.
If the output is too low:
 Check that the electrometer is on.
 Check that the flame is lit.
Create or load a method with these parameter values.
Table 1. FID Checkout Conditions
Column and sample
Type
HP-5, 30 m — 0.32 mm — 0.25 µm
(19091J-413)
Sample
FID checkout 5188-5372
Column flow
6.5 mL/min
Column mode
Constant flow
Split/splitless
inlet
Temperature
250 °C
Mode
Splitless
Purge flow
40 mL/min