EFC type-4 Varian GC-3800 malfunction

[Wajid]

Dears, EFC typ e 4 is installed with hydrogen as carrier, setpoint of pressure is 18 psi and flow rate is 60ml/min. I am getting zero pressure and flow of 79ml/min. What could be the possibilities. GC is not ready and I cannot run any sample.

[Peter Apps]

The first thing that springs to mind is a massive leak. Check with a leak seeker. Is this a capillary split-spltless setup ? or something different ?

Peter

[Wajid]

EFC is installed on packed column, a simple application.
Well I will try to detect any leakage.....Thnx

[Peter Apps]

Is this the EFC module with only mass flow control ? If so it makes troubleshooting easier. Presumably with a packed column you have no split and no septum purge, so the gas flow goes only though the column.

With hydrogen at 60 ml min as carrier I presume that your detector is TCD, so simpler yet, with no fuel or make-up gasses.

Measure the flow at the detector using a flow meter calibrated for hydrogen - a bubble flow meter is simplest.

What flow do you get ?

Peter

[Wajid]

Dear, It was faulty EFC causing the problem. Problem seems to be with the pressure regulation/sensing. It was giving a flow of 100 ml/min after a MS column without showing any column head pressure. No leakages were found. Thanks for your support.