My Split/Splitless Inlet on my 6890 Shows Zero Total Flow

I recently replaced the split/splitless inlet to my GC because one of the gas carrier lines had cracked and was leaking.  The GC repeatedly goes into front inlet flow shutdown despite attaining set pressure.  Looking at the software, there is no total flow through the inlet.  To provide more context, my setup samples a gas streak in real-time, so there is a gas-sampling valve between the inlet weldement and EPC module.

  • Hi

    Check connection of EPC to valve to inlet..

    Check gas cylinder pressure is enough or not.

    May be leak or EPC problem.

  • Hello,

    I have verified that all of the relevant tubing is not blocked by flowing inert gases through all of them.  Additionally, I have painstakingly checked every connection to verify that there are no serious leaks.  However, the system output is stil 0 mL/min for total flow.  Is this likely to be an EPC problem?  Any insight would be appreciated.  Thanks.+

  • If u have two same inlet then by interchanging EPC, You can confirm it..

    Or remove carrier line from EPC then check pressure of inlet if zero then connect carrier line back to EPC and check inlet pressure.if zero again then change EPC...

  • Thanks for the suggestions.  My other inlet is actually a purged packed column, so I cannot interchange the EPC.  I was able to disconnect to the carrier gas line and verify 1) the pressure immediately decreased and 2) was unable to reach the setpoint - indicating that the pressure gauge is likely functioning properly.  Additionally, I used a little leak-detecting solution to verify that a large flowrate of gas is coming out of the split vent line, despite the total flow being measured as 0 mL/min.

    Is there anything else I can do, or should I move forward with the assumption my EPC is malfunctioning?

  • You could have two solutions. 1 The GSV is not in the sampling or injection position thus there cannot be flow through the GSV. 2 You may have a blocked split vent trap

Was this helpful?