"After a few successful stripping runs I decided to try a spirit run over the weekend, but it ended with hot liquid shooting out of the condenser, into a beer bottle, and then a couple of feet into the air.

I cleaned up the mess and did some reading about surging. I found two explanations, one was that the still was running at too high of a reflux rate and that the column was not able to return all of the condensed liquid back to the kettle, which could be caused by too much column packing, and the other was that the kettle boiled up into the column.

I'm using a Brewhaus High Capacity distiller, packed with 11 ft rolls of copper mesh, on a 1500 watt hot plate with the thermostat bypassed. For cooling I have two 44 gallon trash cans outside, and the water is pumped inside with a 980 GPH, 13 foot head aquarium pump which gives a good strong stream. I was running indoors with an ambient temperature of around 70F with very little air movement.

There was one aspect of the copper packing that I was unsure of. I cut 1 foot lengths of copper mesh, rolled them up, and then stuffed them around the cooling tubes at the top of the column. I was concerned that the rolls may have become too tight after stuffing, so I pulled them out and replaced them with loosely packed balls of mesh.

I threw half a liter of raching rings into the kettle and fired it up once again. I wanted to test whether the column could return all of the condensed liquid back to the kettle under full reflux, or if the copper packing was too restrictive. As the head temp started to climb I turned on the cooling water, then dialed back the heat with a motor speed controller. I found equilibrium at 100F head temp with full cooling water to the column. I ran it that way for maybe half an hour, then gradually brought up the power on the hot plate. At full power the column stabilized at 153 to 154F, but there were times when the temp would suddenly drop to 149 to 151F, and then it would rise back up after a few minutes.

I ran full power and full cooling water for 1.5 hours without flooding, so it appeared that the column was able to return all condensed liquid back to the kettle at nearly full reflux. I reduced the cooling water to bring the head temp up to 171F, which produced a nice steady drip out of the condenser. I collected 6 beer bottles half way full. To start it took about 20 minutes for half a bottle (about 6 oz), but on the 6th bottle the time had dropped to a little over 10 minutes. On the 7th bottle I decided that the rate of collection was too high since there was a constant stream instead of a stream of drips. I opened the cooling water valve the smallest amount that I could, and the head temp went from 174 to 172F. Right after that there was some surging, and once again the contents of the column came shooting out of the condenser. It was a little easier to clean this time since I had placed my beer bottle inside a large brew kettle. So, nothing on the floor and nothing lost.

So why the heck am I getting the surging? I've read that when using the Brewhaus 1500 watt hot plate that it can be run wide open, and that temperature adjustments can be made with just the cooling water. So why did a small change in the cooling water, which was meant to lower the collection rate, cause such a flood?

So far the only trick that I have not tried is insulating the column. I see how insulation can help outside on a cool and breezy day, but I didn't expect it to be needed inside out of the weather."

"Mtnwalker2,

Thanks for the through reply. I appreciate your input.

I'm going to pull the packing from my column and shorten the rolls of copper mesh. The booklet that came from Brewhaus says to use 10 to 11 feet of mesh. I used 11 foot rolls, but I'm going to shorten them and pay very close attention to how they are rolled. Any suggestions on how much mesh to use? Maybe less then 10 feet?

Once I get the packing issue resolved then I will practice my technique as you have described."

"I pulled the copper, cut it down to 10 feet (from 11 feet), rolled it again with care, and then attempted a couple more spirit runs with no luck. It appears that I have two problems, and they may be related.

After collecting my second half beer bottle I didn't like the way things were going, so I decided to abandon the run and experiment. I was hearing explosive booming from the kettle, I could feel air being pushed out of the collection hose when it boomed, and the collection rate became unsteady. I knew it was just a matter of time until it started surging and flooding.

The booming in the kettle can't be good for the process so I reduced power to the hot plate in an attempt to quiet it down. As the temp in the kettle went down, I reduced water flow to keep the head temp up. Long story short, I got down to just pot stilling with no water in the head, and the kettle was still booming. So it was not possible to get rid of the booming with heat control.

I shut the still down, considered my options, and then remembered the diffuser plate that came with the still. It was unclear to me whether the diffuser should be used with an electric hot plate, or just with propane. I saw a post on this board from Rick stating that the diffuser is not needed with the smaller still and the 1100 watt hot plate, but I couldn't find anything about the diffuser and the bigger hotplate. So, I had not been using it.

I shoved the diffuser under the kettle and tried again. It made an amazing difference. The kettle was much quieter. It sounded more like a smooth steady boil, with only an occasional faint pop. Without the diffuser I was getting booms even during warm up, but with the diffuser I was able to run full reflux for an hour with smoothness.

I reduced water flow and started collecting slowly. Everything went fine for a couple of hours, and then the booming started again. After collecting about five half beer bottles it started surging, and then flooded.

I could have tried reducing power to the hot plate again in an attempt to control the booming, but it didn't work the first time, and from posts that I've read, it appears that other people successfully run with the hot plate at full power.

I'm not sure if my surging and flooding problem is caused by too much heat, restrictions from the packing material, or from instability due to the booming.

I've tried all the tricks I can think of, including boiling chips, and I'm looking for suggestions. Does anybody else have a lot of booming with their 1500 watt hot plate running full power?"

I used one of the small bags of rasching rings from Brewhaus. It's 1/2 liter of 6mm x 6mm rings.

"Mtnwalker2, thanks for sharing your copper rolling and maintenance tips. Rolling a ten foot length of copper after folding it in half is certainly easier than rolling all ten feet from end to end. You don't need as much space, and you don't need to do as much rolling. Also, if you start from the cut ends, you end up with a roll with no strings of copper hanging off the outside.

I put the collection tube into the beer bottle, but I did not put it into the liquid. I don't think that there was enough back pressure to cause any issues, but I have learned not to do it that way since the long neck of the Corona beer bottle will cause hot liquid to shoot into the air if the column floods.

I've given up for now on spirit runs. I don't know if my flooding problem is due to too much restriction in the packing material, or if it's related to the explosive boiling (booming) in the kettle. When I hear the booming, I also see the tower shake and I get a burst of gas out of the collection tube. This can't be right. I imagine that it could mess up the delicate balance of gasses in the column, and I suppose that in some way it could lead to flooding. Also, when I took the copper out for re-rolling, I noticed that part of the lower roll had changed color. I assume that it was from liquid being forced up the column during the booming.

I purchased a 15.5 gallon beer keg, ordered an adapter kit from Brewhaus to attach my column, and I have some half couplings on the way that I plan to weld into the keg to electrify it with hot water heater elements. This will allow me to by-step any issues that I may have with the kettle and hot plate, and get rid of the booming. If the still floods while using the keg, then I'm either using too much heat, or the copper is still too tight.

While all the booming was going on I wished that I could look inside the kettle to see what was going on. With that in mind, I boiled a gallon of water on the hot plate in a large flat bottom pot. Boiling happened along a circular pattern which matched up with the outer edge of hot plate element, with most of the boiling happening at two points around the circle that were 180 degrees apart.

I tried again with the aluminum diffuser plate from Brewhaus between the pot and hot plate, and found roughly the same thing. The diffuser plate is a larger diameter than the hot plate element, so the boiling circle was larger and closer to the edge of the pot. Also, instead of a boiling circle with most of the boiling happening in two places, all of the boiling was happening at the two spots, and there was no other boiling on the bottom of the pot. I had hoped that the diffuser plate would spread out the boiling area, but instead it concentrated it into two spots.

This explains why the kettle was so much quieter with the diffuser plate. The plate is about he same diameter as the bottom of the kettle, so boiling was happening right at the edge, and the bubbles were traveling up the sides of the kettle rather than up through the middle. I tried boiling water in the same pot on my stove top, which has a spiral element, and the boiling was spread more evenly across the bottom of the pot.

I understand the theory behind using boiling chips. If the bubbles coming up from the bottom of the kettle have to travel through the boiling chips, then they will be broken up. But in my case they don't seem to be working because the boiling is happening in two isolated areas, and the boiling water just pushes the chips aside. Boiling chips would likely work better when using a heat source that heats the bottom of the kettle more evenly. I assume that propane or a spiral heating element would benefit more from boiling chips than a circular heat source such as a 1500 watt cast iron hotplate."

"I agree that something is wrong, but I'm not blaming the equipment. There could be something wrong with the hotplate, but it's far more likely that I've done something wrong or that I've overlooked something important. It may appear that I've done everything right, but ...

I did some boiling tests and described what I saw, but I have not come to any conclusions from the tests. I would have liked to see bubbles forming over a wider area on the bottom of the pot, but I can not say that it's necessary for proper operation.

Since I don't know if my problem is related to the hotplate and kettle, or if it's the column packing, then my intention is to separate the two by using an electrified keg. Once I have the column working correctly, then I'll revisit the hotplate and kettle issue. In time I'll figure out what's going on, and discover the source of the problem.

I understand your concern about buying a hotplate after my reports, but as you mentioned, others using the same hotplate have not complained. If you would like to have Rick's input on this issue then you could send him an email and point him toward this thread. At this point I'm reluctant to point my finger at the equipment, and I have a plan to to find the source of the problem on my own, so I'm not yet ready to seek Rick's help. I try to do as much on my own as possible before asking for help. Although, it is nice to know that Rick is there if I need him.

Also, I like the idea of an electrified keg over a kettle and hotplate. If 240 volts is available, then the heat up time can be reduced substantially over the use of a 1500 watt hotplate. An electrified keg introduces its own set of problems, but everything considered, it appeals to me.

This reminds me of a friend that purchased a recumbent bicycle from ebay. He got the bike and then had a hard time riding it in a straight line. He thought that maybe there was something wrong with the tires, the hubs, or maybe the steering. After he described in detail what he thought was wrong, I hopped on the bike and rode it in a straight line up and down the road. I have been riding recumbent bicycles for well over ten years, and he was a novice. It was the rider and not the bike. So, in this case, I am inclined to say that it's the operator of the equipment, and not the equipment."

"I did another boiling test today and saw the same ring of boiling water, with most of the boiling happening in a couple of spots around that ring, and only a small amount of boiling going on in the middle of the pot. I rotated the pot and saw that the boiling areas moved. I rotated a few more times, watched them move around, and then realized that they were not following the same spot on the bottom of the pot, or the same spot on the heating element.

I was going to try the boil test again with the aluminum diffuser, so I unplugged the hot plate, lifted the pot, and then saw that the middle of the hot plate was glowing a bit red. How could that be? The middle of the element was red, appeared to be the hottest part of the element, but I had almost no boiling in the middle. I put a straight edge on the bottom of the pot and found that it was concave. I had checked it before and it was flat. I let the pot cool, checked it again, and found that it was once again flat. It appears that the bottom of my pot goes concave when it gets hot.

This would certainly explain why I was getting a ring of boiling since the pot was only in contact with the outer edge of the heating element. I suppose that the little bit of boiling that I saw in the middle was from radiant heating or maybe from convection within the small air space between the middle of the pot and the element. This also explains why I had no boiling whatsoever in the middle of the pot while using the aluminum diffuser. The diffuser would have blocked all radiant heat from getting to the middle of the pot.

I put the pot back on my stove and did another boil test. I found that even with a concave bottom that I had even boiling. I checked my stove element with a straight edge an found that it was nowhere near flat and that a pot could not be in physical contact with all of the element.

I believe that my stove top element heats primarily with radiant heat, and that physical contact is not entirely necessary. Whereas the heating element on the hot plate needs to be in full contact with the bottom of a pot.

So, with a flat bottom boiler I believe that the hot plate will work correctly, but if the bottom is not flat, then a glowing red spiral heating element may work better.

My first attempt at a spirit run was done with the strippings I got from three ferments. Each ferment yielded just under two gallons. The first gallon was about 60% and the second was about 30% ABV, so I was probably working with under 6 gallons of 45% ABV. The first time the column flooded I lost a lot of alcohol on the floor, and I'm sure that the ABV dropped quite a bit. I checked what's in the boiler now and it's down to 15%. So, I might have been above the 40% that you recommended on my first attempt, but I'm sure it was lower than that on later attempts.

I'll try it again with cleared wash, but I don't have any now and I don't even have anything fermenting. I will also try some anti-foaming agent to see what happens. I don't have another heat source to try. I thought about picking up a propane burner for testing, but I really don't want to be outside with temps in the teens and twentys. :-)

Thanks for your input Rick"