septum purge shotdown

[che313]

in agilent 7890 it gives me that the septum purge flow is in negative and could not reach the setpoint which is 3ml/min. what do u think the resone is? the front inlet pressure is 12 psi and the injector temp is 250, the column is hp-5ms, 30m, 25um, 0.25um film and the flow is He 1 ml/min

[Consumer Products Guy]

What is your split flow?

What is your carrier gas pressure at the cylinder regulator?

[Peter Apps]

Are you sure that you have the column diameter correct - I would expect 250 um, not 25 um. Then, depending on the column temperature the inlet pressure is too high for the flow rate - check that you have selected the right carrier gas.

Peter