Thermostatically controlled propane burner

[Goodpapi]

I have read around for a while on many different topics, but I could not find any information on this. It seems that with with electric elements you are able to have your heat output controlled by a thermostat, but with propane gas burners you are required to to actuate the regulator manually in response to your peak vapour temperature (in my case the analog thermostat at the top of my reflux column). This process seems to always have my actuation of the regulator be in a late response to temperatures running too high, too low, or an irregular flow of product. My thought process, was to have the propane gas actuated by the peak column temperature directly (the temperate would be decided by me periodically if not before hand, sort of like a cruise control). Looking around, I came across a thermostatically actuated propane valve. These devices are used for propane water heaters, and would actuate the gas flow based on the desired temperature of their location. They come with a pilot light for safety, and my plan is not to leave the still unattended. If I set the temperature of the valve, adjust my reflux accordingly, theoretically it should run on its own for hours. If anyone has any thoughts or experiences, please let me know!

[Pure Old Possum Piss]

Water heater thermostats won't work. Just adjust your propane fire until you get the product flow you want and forget about thermometer and thermostats. The off/on temp range is too wide for a still.

[Salt Must Flow]

You cannot control a still by temperature.

Just adjust the heat to control the take-off rate. Think of your still as though it is a pot of water. More heat = more steam. Less heat = less steam. The condenser condenses the steam. Think of it like that and you'll get it.

[Saltbush Bill]

As above you can't control a still with a thermostat, thermostats turn power off and on which is not what you want when distilling.
You need constant steady power/ energy under a still, not on and off.
Seems to me that you are trying to control the temperature of the boiler , which is not possible.
The following link is worth a read.
https://www.kelleybarts.com/PhotoXfer/R ... gMyth.html

[Saltbush Bill]

What type of reflux still are you running, a photo would help.
With reflux stills you don't necessarily want the Reflux condenser at maximum cooling.
In theory the water leaving the condenser should be warm to hot, over cooling the reflux is not beneficial when it comes to getting the best performance from a reflux still.

[Goodpapi]

My entire setup is off grid, it is solar powered so I have enough electricity for everything except an element, hence the propane. Needless to say I am not there at the moment but I have a photo of my column when I first got it a while back, I’ve added a gin basket since then. It is a 4” column with 5 bubbling plates. I think it’s 51” tall. Its propylene glycol cooled by a high flow circulation pump to an external radiator. The pot is fully insulated with 2” rockwool, jet burner fired, and is equipped with a top mounted agitator. I will take a photo of the whole rig when I’m out there next, I’ve had no need to until now! I’m still mulling over the other information you’ve given me.

[shadylane]

The pot is fully insulated with 2” rockwool, jet burner fired,

I like folks that think outside the box, but this idea isn't workable for what needed.
What's needed is a burner to run at a steady and controllable rate, not off and on.

[Saltbush Bill]

(in my case the analog thermostat at the top of my reflux column).

From that I automatically assumed that you were running a " packed reflux column" I shouldn't assume things.
I have a feeling that a lot of others here would have thought the same way.
While these stills do rely on some reflux to keep the plates loaded they are not a true reflux still imo.
Instead of a reflux condenser they utilize a dephlegmator which is a partial condenser which is used to separate the different components of a multicomponent vapor stream..
https://www.thermopedia.com/content/691/
In Distilling circles these stills are normally referred to as plated column stills....or sometimes on this forum as " Flutes"
Not trying to be picky but it helps us help you if the correct words are used.
If you want to continue using gas under your still I would suggest a good quality adjustable regulator.
Ive used one of these now for about ten years and its one of the best things Ive done as far as improving the control-ability of heat input under my boiler.
If you do go down this path , stick to this size 1 to 15 PSI anything bigger is just to hard to adjust, 1 to 15 PSI will give you all of the heat that you will ever need and is extremely user friendly. I have used the one in the photos under 2 ring , 3 ring and four ring burners , it works well under all.
As a side note , a thermometer is not a necessity when running a plated column, run the same as a pot by judging out put speed of product.

[Pure Old Possum Piss]

(in my case the analog thermostat at the top of my reflux column).

From that I automatically assumed that you were running a " packed reflux column" I shouldn't assume things.
I have a feeling that a lot of others here would have thought the same way.
While these stills do rely on some reflux to keep the plates loaded they are not a true reflux still imo.
Instead of a reflux condenser they utilize a dephlegmator which is a partial condenser which is used to separate the different components of a multicomponent vapor stream..
https://www.thermopedia.com/content/691/
In Distilling circles these stills are normally referred to as plated column stills....or sometimes on this forum as " Flutes"
Not trying to be picky but it helps us help you if the correct words are used.
If you want to continue using gas under your still I would suggest a good quality adjustable regulator.
Ive used one of these now for about ten years and its one of the best things Ive done as far as improving the control-ability of heat input under my boiler.
If you do go down this path , stick to this size 1 to 15 PSI anything bigger is just to hard to adjust, 1 to 15 PSI will give you all of the heat that you will ever need and is extremely user friendly. I have used the one in the photos under 2 ring , 3 ring and four ring burners , it works well under all.
As a side note , a thermometer is not a necessity when running a plated column, run the same as a pot by judging out put speed of product.
regulator 1.jpgregulator 2.jpgregulator 3.jpg14348057883_41fe0fed9d_z.jpg

100%

[bilgriss]

You want to control the amount of energy you are putting into boiler, not control the temperature. That's counter-intuitive to many, since they see the temperature rise in the vapor path as a run progresses, but whatever is in the pot will be the temperature it will be, depending upon how much alcohol and water it has. Water boils at about 212F no matter how big the flame. Alcohol about 173F. As alcohol is driven off, the vapor temperature rises towards a theoretical terminal value of 212. But as a stiller, you want to target a constant amount of energy to keep the output at the right level, not control the temperature. happens no matter what. If you have a thermostat on your heat source, it will just go up and down within whatever band it operates, causing a poorly controlled output of lower quality.

[Yummyrum]

Goodpapi

Are you scratching your wondering why all six members so far have told you that you can’t run a still by temperature ?

Are you thinking they all have it wrong ?

I would blame your Highschool science teacher . I bet they said you can seperate ethanol because it boils at a certain temp .

Well they were correct 100% pure ethanol will boil at 78.3°C .
But when there is water and other stuff in the boiler it no longer is true .

The 6 members that replied are all correct . It also sounds like you were running your gas burner correctly by manually adjusting it .
Adding temperature control and it will all turn to shit real quick.

There are a plethora of posts on here from folk that tried to use a PID controller to control an electric element by temperature .
They all conceded it was a dreadful waste of time

Now , temperature control during mashing is a thing . That works