VARIAN 450 GC Pressure doesn't increase

[migliuca]

Hello everyone,

Sorry for my English but I am not a native.

I am writing you because I have a pressure problem in GC that I am using. After a thermal treatment of the column for reactivation, I reconnected the column at GC but the pressure doesn't increase at the pressure value that is setting (23 psi). The pressure shown on the displays is 10 psi.

Who could help me?

Thank you

[adler_LAB]

Make sure your coloumn didnt break during that process.

You could test your column for any mirco fissures. connect the one end to the injector to have the gas flow you need. seal the other end with an old septum and see if the pressure goes up. If that works you know the leak must be after the injektor and the column.

reconnect the column to your detektor with new materials, new connection screw and ferrules and try again.

i dont see any reason for any other leak yet. to test leaks in the injektor you could just plug the end after removing the coloumn or doing a pressure calibration run.


if you use a pre column to catch the dirt and you can plug the one end of the coloumn agian and put the connection in IPA. You will see bubbles comming out it there is a leak.

[seet88]

Hi,

I agree with above, try to notice have flow on the column. Another suggestion is can you put a blank nut to block the inlet? Then u try set different pressure and notice the pressure? If can not achieve try to change septa those. If still cant maybe due manifold problem as loosen can not reach the setpoint of the pressure.

Thanks
Seet