Boiler temp when using thumper

[Sgt-Greywolf]

Mornin' from the Ozarks of SW MO. Looked and looked but couldn't find an answer in the different threads on thumpers. I run a 5 gallon pot still. I've only used my thumper a couple of times and each time I do, it takes so long to finally get the thumper producing that my boiler is at the temp I would normally be shutting down on a run without it. I've read that preheating the thumper is not necessarily a good idea??? Anybody else have this problem? Is there a fix?

[jb-texshine]

Mornin' from the Ozarks of SW MO. Looked and looked but couldn't find an answer in the different threads on thumpers. I run a 5 gallon pot still. I've only used my thumper a couple of times and each time I do, it takes so long to finally get the thumper producing that my boiler is at the temp I would normally be shutting down on a run without it. I've read that preheating the thumper is not necessarily a good idea??? Anybody else have this problem? Is there a fix?

Insulation ,linearm and thump .keep distance between the thumper and boiler as short as possible. Crank the heat up .

[Sgt-Greywolf]

Thanks Texshine. What would you suggest for insulation? You say crank up the heat, but I'm afraid if I do, I might hit boil and have it puke. If I'm running that hot in the boiler, won't I have passed the temp where the ethanol is? Actually I pass that temp WAY before the thumper goes active.

[jb-texshine]

The thumper will catch the puke.foam pipe insulation for the pipe of course,my primary is wrapped in a thick woven fiberglass welders fire blanket thumper is wrapped up in the insulation jacket from a old hot water heater cylinder. The thermometer is really kinda useless... Its never going to tell you anything going by any temp you think is meaningful. The best use is to ignore it until you get your first drop out of the condenser then check it. That they or a bit lower will be your clue to get ready from then on. Other than that, run it with the heat cranked up till you get drips then cut the heat and run by the stream size. Small as or smaller SOLID stream. Make sure to insulate the tops of the boiler and thumper also.
Jb

[Sgt-Greywolf]

Thanks. I'll take your advice.

[skow69]

Hi Sarge. It sounds like you have fallen for the Magical Boiling Myth which says that all the ethanol will boil off at 173f. In reality, pure ethanol boils at 173, pure water boils at 212, and a mixture of the two, like your still charge, will have a boiling point somewhere in between, determined by the relative proportions of ethanol and water. You can't control the boiling point. The temperature will not go above the BP, and the mixture will not boil below it.

Which brings up the next point: it is not boiling that causes pukes. Your wash is boiling anytime vapor is being produced (anytime distillation is happening). If you add more heat it will boil harder and produce more vapor. Reduce the heat and the vapor (and distillation) slows down until it stops.

Finally, if your are not happy with the time it takes for your thumper to come on line, there are basically three things you can do. In order of effectiveness:
1 Add more heat! (Insulating is a form of this.)
2 Reduce the size of your thumper charge.
3 Use higher ABV thumper charge. (Lowers the boiling point.)

For a better discussion of distillation theory, see http://homedistiller.org/howitworks.pdf (many thanks to Mike Nixon) or the Theory section on the parent site (easier reading than the pdf).

[Pikey]

Hi,

Where are you measuring your temperatures ?

In mine, I run until the head temperature gets to 99 - 103 C, depending on how bored I am by that time.

When the head temp is at those temeratures, the actual boiler charge (Measured with another thermometer strapped to the tank ) is only around 90 C - How does that compare with your temperatures ? Are you shutting down too early and leaving a lot of product in the pot ?

[Sgt-Greywolf]

Skow and Pikey .... Seriously appreciate your input. Skow, your info helps a lot. Since I don't have any insulating materials at the moment, I'm going to do both .... reducing the thumper load and upping the abv.

Pikey, I usually shut my run down when the boiler temp (taken in the center of the boiler) hits about 208f. Definitely well into the tails by then. On a five gallon wash, my yield is usually about a gallon + -.

[imeasystreet]

You failed to state the size of your thumper. My guess is that it is too large compared to the rather smallish pot, so it takes a long time to get it to a temp high enough to make vapor to come out of the thump. Charging the thumper acts as a heat sink as well. In a previous reply "The thermometer is really kinda useless... ", I agree.

[Sarge410884]

I am measuring at the top of my boiler and at the connection to the thumper which is copper and is probably a 15 inch length of copper tubing on a 5 gallon boiler and a 2 gallon Thumper
Sarge410884

[Sarge410884]

My head temp will be 197 to 208 towards the end of a run
Sarge410884

[Sarge410884]

At 197 to 208 f i am on the end of a run generally, depending on abv and how bad the tails get
Sarge410884

[Sarge410884]

I am getting prepared to try out my thumper and this question came to mind
Sarge410884