Pressure relief valve three chamber still

Hello everyone,

I'm looking for some insights into the pressure regulation system used by Leopold in their bottom chamber setups. Does anyone know if Leopold incorporates a Pressure Safety Valve (PSV) directly in the bottom chamber to manage pressure in case of unforeseen events? Or do they typically connect all the chambers to a 2-inch pipe, with the PSV mounted on top of it?

In the latter scenario, I'm curious about how vapor management is handled. Would some of the vapor escape through this pipe? How is overpressure controlled, especially in situations where there might be an obstruction?

Any technical insights or references to how Leopold addresses these challenges would be greatly appreciated. I'm trying to understand the intricacies of their system for a project I'm working on.

Thanks in advance for your help!


  • edited November 2023

    There are no obvious PRV or Vacuum Breakers visible in any photos I just looked at, but there are also no photos that I can find of the back of the still.

    If there is a PRV, there can not be shared across multiple chambers, as it would be the path of lowest-effort for vapor to flow, creating a bypass.

    Keep in mind, you rarely see a PRV attached to each plated section of a column, so it's not out of the realm of possibility that there is not a PRV on each section.

    Given the unique operating conditions, and the fact that it's running solids, it's not a bad idea.

    You never want to use a PRV as a pressure regulator, ever.

  • edited November 2023

    Todd mentioned in an interview that he uses a railway car pressure relief/ vacuum relief valve on the his still.

    You can see valving on the right side where he'd open the vacuum relief valve then the chamber drain.


    450 x 800 - 88K
  • edited November 2023

    Hey @Bolverk you are taking about that 2" stainless steel pipe (red selection) connected to the top of each chamber with the valves or you referring to that probably 1" pipe coming from the bottom chamber only at the back (blue selection), because if its the blue he is just using for bottom chamber as I was thinking because is were you are injecting live steam.


    chamber still 1.jpg
    450 x 800 - 67K
  • that 2" stainless steel pipe (red selection) connected to the top of each chamber could be the feed line or cleaning line

  • @DMdistilling said: that 2" stainless steel pipe (red selection) connected to the top of each chamber could be the feed line or cleaning line

    That is very likely the vent that allows for smooth liquid transfer from chamber to chamber.

    When liquid is exiting a chamber there will be sucking or vacuum action. When liquid enters a chamber there will be blowing or air discharge.

    Without venting liquid transfer would take forever. Think of the vent cap on a fuel can.

    StillDragon North America - Your StillDragon® Distributor for North America

  • The red section is the venting valves I'm talking about.

    If you look between the red and blue section you highlighted there is a pipe going to a valve at the beer chamber that looks to be for filling.

    I should add that it's entirely possible I'm wrong, this is just the best I'm able to put together with the few pictures that are available on the internet.

  • edited November 2023

    I think @Smaug's comment - opening the anti-vacuum port to allow the contents to drain, is probably the more important design aspect.

    If you are concerned about pressure issues, just install a PRV in each section, done, call it a day.

    Actively regulating pressure? I don't think that's the case, and I've never seen any still design that needs to operate at some bleeding edge of pressure that would require some kind of (wasteful) active regulation.

    I have a tank vacuum break/vent valve similar to that on my HLT that looks very, very similar to that:


    It has a very low weight spring so that it can either vent or vac, but otherwise has a light seal to keep out dust, bug, or otherwise from getting in.

    air and vacuum relief tank vent valve_tvpc200-300_color_lg_watermarked.jpg
    800 x 646 - 34K
Sign In or Register to comment.