CCVM - Corrugated SS Coil not enough Knockdown Power

[VincentPrice]

Hi everyone,
I recently built my first still. It works great in pot mode but I'm having trouble in CCVM mode.

I use a 2" Triclamp system and therefore a 3/8" Corrugated Stainless Steel coil (IIRC 5' long) as a bigger one won't fit. My boiler is a stock pot on an induction hot plate that can't really go below 1700W in order to avoid cycling.

My setup is just an open 4" long pipe above the T-Piece with the coil wrapped around itself and wedged into the pipe.

Even with the water tap on full blast the coil will knock down most but not all vapour. There is visible vapour coming out of the top. Not much but there is. The water comes out of the coil relatively cold. I only experimented with water and vinegar so far during cleaning runs but alcohol should be even worse.

Is the coil just too small? I can't really find any other fault.

Would a longer pipe and coil above the T-Piece be a solution? I would like to avoid having to do a copper coil as I have neither skill nor desire to build one and don't know where to buy one in Europe.

Or am I doing something else wrong?

Thanks!

[Swamptrout]

Dont rely on the water / vinegar cleaning run for an indication on how the cooling will perform. Boiling temps are way different.

In a ventilated area, see how it goes on the sac run, u will be surprised how easily you knockdown vapour.

[Sporacle]

For mine 4 inches above the t is a bit short, I have a 12 inch SS 2 inch section above my T with a double wound copper condenser. I would think that my reflux condensor would not be able to knock 1900w with a section that is only 4 inches above the take off. (Edit, it could as I could drop the coil deeper, but that would greatly reduce my take off rate)
No experience with CSST condensors but someone will be along soon
As stated above, water and vinegar behave differently to alcohol

[Boozewaves]

I had the exact same problem on my 2.5 inch wide ccvm column . Kimbodious suggested using dish scrubbies and that worked perfectly , I had to put some around my product condenser too . take a magnet with you to the supermarket and get some non magnetic stainless scrubbies , boil them a few times first in a saucepan or something to get rid of the oils they have on them and they will be fine . mine were from Asda . make sure the coils in the CSST are not touching for best results as well although scrubbies in between coils are fine .

as Swamptrout said , there will be a difference when you do a sacrificial run and the runs afterwards that are drinkable . Alcohol boils somewhere in the 70's and water boils at 100 but you may need scrubbies

your 4 inch piece above the tee should be fine , I had to cut mine down for some reason which I can't remember and it was about that big afterwards and worked fine

[Demy]

Running with vinegar and water requires much more power than alcohol, so there is likely to be excessive acceleration of the vapor making it past the coil. The others have given you great suggestions, try alcohol and if you are not satisfied edit. The heating system. should be adjustable, consider if a minimum of 1700w is suitable for your system ...

[VincentPrice]

Thanks everyone, you have given me great pointers.

It seems my view was oversimplified. I assumed basically that since water/vinegar has a higher boiling point than water/ethanol, it would take less cooling "power" by the coil to condense it back to liquid form. Sorry, difficult to express with my limited understanding of physics and in English. However it seems that it's quite a bit more complicated. I will try a sac run with alochol and hope for the best before making adjustments.

I had the exact same problem on my 2.5 inch wide ccvm column . Kimbodious suggested using dish scrubbies and that worked perfectly . make sure the coils in the CSST are not touching for best results as well although scrubbies in between coils are fine .

I was originally planning to use copper scrubbies as I do in the column below but the 2" pipe is just too narrow. I can barely wedge the coil into it, no way around it unfortunately.

[Chauncey]

Can we get a pic of the coil and the top of the column

[kimbodious]

The CCST RC on my CCVM is not a coil, more like a “twist”, it works just fine.

Yes you need to have good contact between the RC and the wall of the RC chamber, hence the addition of the SS potscrubbers.

[bluefish_dist]

As mentioned above weave in a scrubbie or two to slow down the vapor. Also I would increase the column available above the T. Imho 4” is not enough. I would go 12” if it was me. With 3/8 in a 2” you should be able to do a single feed down the middle and a coil around the outside. This will be more efficient than a twist.

[Setsumi]

I think 4" above takeoff is a bit short. My CCVMs have at least double that above and the coils are about 2" below takeoff for full reflux.

[VincentPrice]

Update: It works!

I managed to wrangle two copper scrubbies on the coil and into the pipe. It's a really tight fit now.

Started a sacrifice run and it works great. Even with the hot plate at full power of 3500W it knocks everything down and the product comes out at around 90% abv.

Thanks so much everyone!