Pressure control on material column and solvent tank on Terpenator MK4c

I’m using a Terpenator MK4c with 70/30 nbutane/propane. How do I keep the pressure in my material column and collection pot lower than the pressure of my solvent tank until I’ve injected the desired amount of solvent? I always vacuum the whole system down to -22hg (going for -29, haven’t diagnosed that issue yet) but once I start injecting the solvent, the pressure on the collection pot quickly climbs up past 30psi, which is sometimes higher than the pressure on my chilled solvent tank.

Either chill the base, use a pump, or a chilled sucker tank.


I would also highly suggest making sure your getting the vac down under at least -26hg with this mix optimally -28.8hg. That little bit of of vac at these levels may not seem to significant but when your extracting with these higher pressures due to the propane it will help on butane side with of the mix to help the vapor to condense back to liquid when chilled. Is there any way you can buy,use or borrow a 2 stage rotary vane to vac down your material column and collection chamber?. Also have you tried pushing nitrogen threw system then pulling vac with the material column in cryo assuming its sleeved and the collection dish on a dry ice/acetone slurry to get that extra bit of vac?.

What is the gauge on your solvent tank reading when fully chilled? At room temp?

Is the collection dish jacketed?

There can be multiple solutions to your situation if we know more of the variables. :thinking::+1::+1:


I’m not the guru your after but i know some question you need to answer so they can help you.

  • what’s your elevation?
  • can you pull your vac oven to -30 with that same pump?
  • can you pull your system down to -22 and close off the valve to the pump and the system hold this -22 for an hour?
  • do you have a dewaxing sleeve and if so are you chilling the material column?

Are you supposed to chill the sleeved column before you load it n the solvent or do you load in the solvent then chill the column.

1)evacuate air
2) chill column
3) run cold solvent through material
Thats the quick and dirty :sunglasses:


I’m gonna chill the base, thanks!

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