Huffing Pot

[Oak Pollen]

I have a 5 gallon copper pot and in the past, used a worm in a 5 gallon bucket. It was such a pain in the rectum I built a Liebig condenser. It is 32” from input to output, 1/2 inside of a 3/4 inch copper. The thing starts blowing some air with product at about 208 degrees pot temperature on a stripping run. I can turn the water up all of the way and it doesn’t effect it.
Keeps right on huffing. It blows bubbles about every 20 minutes. My solution has been to put a 1/2 to 3/8 reducer and extend the drop tube into the jar, that works as far as not letting good stuff escape, but can someone tell me what is happening?
Oh, PS if I do a slow drip, cut the heat way down, it still happens.
Anyone have an idea what is going on.

[still_stirrin]

Is it sucking air in the end of the spout, or blowing vapor out?

Puffing vapor out is the boiler over powering the condenser. Gotta’ turn down the heat.

Huffing is a vapor collapse in the lyne arm, and it suck air back into the condenser. Slow the coolant water down so you get a temperature gradient in the product condenser. The water out of the condenser should be warm to hot to the touch when you’re balanced.

Is the product coming out of the spout hot, or cold?
ss

[still_stirrin]

Another thing, if the vapor velocity out of the potstill is too fast, it won’t have time to condense inside the Liebig. How large is the vapor tube in your vapor line, from riser all the way through to the condenser?

Going from a 2” riser, especially when powered by a propane burner, to a 1/2” vapor tube can result in excessive speeds. Again, your boiler is outrunning the stillhead, or specifically to vapor piping.
ss

[Oak Pollen]

The vapor is going out. The condenser never gets hot at the outlet but you can’t put your hand on the vapor arm. I am running well water and it’s right at 48 degrees right now, the temperature of the product is 53. I suspect that the water is too cold. Thank You!
The vapor line is 1/2 with 12 awg around the outside. I also have a 18 inch long copper strip up the center of the V tube.

[nerdybrewer]

I have a 5 gallon copper pot and in the past, used a worm in a 5 gallon bucket. It was such a pain in the rectum I built a Liebig condenser. It is 32” from input to output, 1/2 inside of a 3/4 inch copper. The thing starts blowing some air with product at about 208 degrees pot temperature on a stripping run. I can turn the water up all of the way and it doesn’t effect it.
Keeps right on huffing. It blows bubbles about every 20 minutes. My solution has been to put a 1/2 to 3/8 reducer and extend the drop tube into the jar, that works as far as not letting good stuff escape, but can someone tell me what is happening?
Oh, PS if I do a slow drip, cut the heat way down, it still happens.
Anyone have an idea what is going on.

Without seeing your liebig I have to ask a couple questions.

First off I have a similar setup but my liebig isn't nearly that long.
My boiler is a 15.5 gallon keg and I use propane.
My much shorter liebig knocks down all the vapor I can produce even at full heat.

What size water inlet and outlets are you using?
Are the inlet and outlet at each end of the water jacket?
Do you attach your water source at the bottom (nearest the opening) and let it out at the top (nearest the column)?
Is the water in cold and the water out hot?
How do you control water flow?

[Oak Pollen]

I am running a 5/8 garden hose both in and out. I am not sure what to call my water control but it is a type of ball valve. I believe you are onto something. I am probably not getting the water low enough.
The inlet is at the bottom, the out water is warm, never hot.
Stirring and Brewer, thank you.
One question left, would I be better off shorting my Liebig or using a rotary valve instead of a ball valve?

[Yummyrum]

[Oak Pollen]

Yummy, you nailed it. A pic is worth a bunch! Thank You All!

[Oak Pollen]

Ok. First thing, thank you to everyone who replied to my post. I now know what is going on, thanks to Yummyrum’s video.
Let me set the stage, I have a garden hose stretched across the ground (150 ft.), from a well. The air temperature is 45 degrees. I had a ball valve on the Liebig, but after Yummy’s video, I stole Momma’s spigot from her garden and put it on the Liebig. It did not stop the huffing without constant adjustment, my water is to damned cold. Next time I get to town, I will get a 1/4” rotary valve and try it. Right now I would probably be better off going back to the worm or getting a small pump to feed the Liebig out of a bucket, but it is just to interesting to give up!

[zed255]

Huffing is generally not a serious problem. So long as you are fully condensing the vapour it is not unsafe. You are correct that really cold water can make the issue worse.

In my region cold tap water is generally about 12*C pretty much all year round, so I've seen huffing on my liebig condenser. I have reduced it with adequate control over water flow. I ended up using and adjustable water pressure regulator set to about 10-12 psi when water is flowing. This made a relatively inexpensive needle valve more usable. It is surprising how little water flow is needed. My condensate comes out cooler than room temperature, but the outlet water of the condenser is too hot to keep your fingers under with a bare trickle of cooling water flowing.

[MartinCash]

Stuffing a bit of stainless or copper scrubber at the mouth of the liebig also helps. That's all I needed to do to mine to make it tolerable.

[Oak Pollen]

Thanks for the tips. I do like the regulator idea, but remember my hose is on the ground, will that low water flow cause freezing when it gets colder? NBD I can hold off for a warmer day, just wondering.