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DIY glycol chilled plastic conical fermenters

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Looks good. Maybe I missed it some pages back, but why are you using glycol and not water? Looks like you have the temp above freezing, and water is better at heat transfer than glycol.....

I think he started out with just water but was getting freezing at the coil.
 
Looks good. Maybe I missed it some pages back, but why are you using glycol and not water? Looks like you have the temp above freezing, and water is better at heat transfer than glycol.....

It's a mixture of ~30% glycol and 70% water. You can keep the temperature around freezing, but at the evaporator coil, it will be significantly below freezing.

For instance, for a test run I ran water through the system as I didn't want to waste glycol if there were any leaks. I kept it at 40 degrees. A few hours later I checked back and there was at least an inch of solid ice on the coil. From what I've read, you need to have at least a 20 degree buffer before it freezes or that can happen.

Also, I change the temp of the glycol depending on what I'm fermenting. Right now I have a weizenbock, blonde, and pilsner going. The pils has to be ~50 degrees and the other two are in the upper 60s. If I were to drop the temp lower than I have it now, I'd get much bigger temp swings in the conicals fermenting the ales. This is because when the ball valve closes, you have a good deal of chilled glycol that sits in the lines, further cooling your beer. So, don't set it any lower than it really needs to be. Also, it saves some money in utility bills.
 
If I were to drop the temp lower than I have it now, I'd get much bigger temp swings in the conicals fermenting the ales. This is because when the ball valve closes, you have a good deal of chilled glycol that sits in the lines, further cooling your beer. So, don't set it any lower than it really needs to be. Also, it saves some money in utility bills.

Really great system you've built there.
You could plot a hysteresis curve or perhaps program in some of the parameters, so the valve closes before the target temperature is reached, thus anticipating and correcting for the remaining cooling capacity in the coils at that tank's temperature and volume.
 
Really great system you've built there.
You could plot a hysteresis curve or perhaps program in some of the parameters, so the valve closes before the target temperature is reached, thus anticipating and correcting for the remaining cooling capacity in the coils at that tank's temperature and volume.

I could, but the curve would change if I changed the glycol temp. As it is, I just set it a degree or two higher than I want it to ferment at and set the hysteresis to 1 degree. Works pretty well.

I've slowly been putting together instructions to build one here:
http://plasticconical.com/

I still need to do the instructions for the controller, but a parts list and photos are there for everything else.
 
...The system seems to have settled in to a pretty decent rhythm:
Graph.jpg


That's with a czech pils, blonde ale, and weizenbock in the fermenters at the moment....

Looking at the graphs, it's really consistent for #1 and #3. But what's going on in fermentor 2 (the gray graph)?

In comparison, the fluctuations of the glycol temp seem so large (DeltaT=10°C), but have no effect on performing its actual duty. The AC is neither working overtime nor fibrillating, which proves your excellent system's design.
 
Looking at the graphs, it's really consistent for #1 and #3. But what's going on in fermentor 2 (the gray graph)?

In comparison, the fluctuations of the glycol temp seem so large (DeltaT=10°C), but have no effect on performing its actual duty. The AC is neither working overtime nor fibrillating, which proves your excellent system's design.

The AC unit is really overkill for 3 10 gallon conicals, but it's the smallest unit that's available. I know of at least one brewery using a 14k BTU AC unit to chill 3 10 barrel fermenters. The hysteresis is set to 8 deg F for the glycol to minimize the cycling of the A/C unit. As long as you don't get ice build up on the coil, it works great at least past the 86F ambient temps I've seen in the garage.

For ferm 2, I think that's just a result of the cold glycol sitting in the coil. I've had a couple different batches in there and as long as I have a lager and something in the upper 60s in the fermenters at the same time, that tends to happen. The good news though is that the beer still turns out great.

If I have all three of them with ales fermenting in the 60s and can turn the glycol temp up a bit, that effect doesn't happen nearly as much.
 
Well, it looks like it wasn't the glycol left in the lines causing the drop. The blonde was finished today. I replaced it with an oktoberfest lager and the same thing happened.

I think I found out what the problem is though. I think it's the 12V driver card having a bit of signal bleed from a neighboring channel. Seeing as there are 8 inputs and I'm only using 3 of them, I was able to move the one for ferm 2 a ways away from the others. It looks like ferm 2 has settled down now and should be good to go.
 
Well, it looks like it wasn't the glycol left in the lines causing the drop. The blonde was finished today. I replaced it with an oktoberfest lager and the same thing happened.

I think I found out what the problem is though. I think it's the 12V driver card having a bit of signal bleed from a neighboring channel. Seeing as there are 8 inputs and I'm only using 3 of them, I was able to move the one for ferm 2 a ways away from the others. It looks like ferm 2 has settled down now and should be good to go.

post a final chart once you see things settled down if you would? I'm a maths nerd and really dig seeing the proof of the elegance of your system.

Been following this thread since it started: Cheers on a great job!
 
This is really an impressive build and the detail you have provided here and on your build site is top notch. This is my favorite of the current build threads right now.

I'm still trying to figure out one thing about your plumbing:
Say all valves are closed and none of the fermenters is receiving glycol and the main glycol line continues to circulate. What keeps glycol from entering the hot side return from the fermenters and circulating through the fermenter in reverse? I'm sure it is obvious, but I can't quite figure that one out.

I copied a photo from your website and placed an arrow at the spot I'm wondering about.

Another thing that someone else asked about was the use of individual pumps for each fermenter. If someone were to use a simple STC-1000 to turn pumps on and off, there would be no need for a solenoid valve...or would you just wind up with a siphon? Sometimes my razor sharp mind just does not comprehend.

return leg.jpg
 
Nevermind, I just read my post and my question made the answer quite obvious. The valves are closed so nothing can flow through in reverse. DOH!
 
Nevermind, I just read my post and my question made the answer quite obvious. The valves are closed so nothing can flow through in reverse. DOH!

haha, yup. The quick disconnects mean you can also disconnect and fill one of the fermenters while the others are working.
 
Another thing that someone else asked about was the use of individual pumps for each fermenter. If someone were to use a simple STC-1000 to turn pumps on and off, there would be no need for a solenoid valve...or would you just wind up with a siphon? Sometimes my razor sharp mind just does not comprehend.

I suppose you could do it with 4 STC-1000's, but at that point you're saving ~$80 on the cost of the BCS-460, which would be offset by the extra 3 pumps you'd need to buy. You'd also lose the ability to automate lagering schedules, graph temps over time, and a web interface.

You'd have to change up the plumbing too. There wouldn't be a need for the motorized ball valves, but that was ~$120 of the entire cost of the project. So, not a gigantic deal.

Also, if anyone plans on building one in the future, don't get solenoid valves. Make sure you get motorized ball valves. Solenoids have really small openings for flow. So, all you need is one small piece of ice circulating in the system to stop glycol flow to your fermenter. MBVs are $15 more, but worth it for the added safety. It's also handy to get the MBVs with position indicators on them so you can glance and see which fermenter is operating at any given time.
 
Been looking at the awesome diy and was searching specifically for the kinds of pumps necessary for pushing the glycol thru the system but didn't find that info...can you repost that info for those of us who are a bit more challenged in finding our arse from a whole in the ground....thanks
 
Been looking at the awesome diy and was searching specifically for the kinds of pumps necessary for pushing the glycol thru the system but didn't find that info...can you repost that info for those of us who are a bit more challenged in finding our arse from a whole in the ground....thanks

Parts list is available here:
http://plasticconical.com/glycol-chiller

Any submersible pump around 1/6 HP will work fine. You can go above that, but it's unnecessary. I think I paid ~$40 for the pump I'm using.
 
Well, it looks like it wasn't the glycol left in the lines causing the drop. The blonde was finished today. I replaced it with an oktoberfest lager and the same thing happened.

I think I found out what the problem is though. I think it's the 12V driver card having a bit of signal bleed from a neighboring channel. Seeing as there are 8 inputs and I'm only using 3 of them, I was able to move the one for ferm 2 a ways away from the others. It looks like ferm 2 has settled down now and should be good to go.

Glad you fixed that channel. The chart looked very sloppy, but not sure about the actual temps, they may have been just fine though.

If you ever feel the urge to build another one, I'll be happy to take your prototype. :D
 
I suppose you could do it with 4 STC-1000's, but at that point you're saving ~$80 on the cost of the BCS-460, which would be offset by the extra 3 pumps you'd need to buy. You'd also lose the ability to automate lagering schedules, graph temps over time, and a web interface.

You'd have to change up the plumbing too. There wouldn't be a need for the motorized ball valves, but that was ~$120 of the entire cost of the project. So, not a gigantic deal.

Also, if anyone plans on building one in the future, don't get solenoid valves. Make sure you get motorized ball valves. Solenoids have really small openings for flow. So, all you need is one small piece of ice circulating in the system to stop glycol flow to your fermenter. MBVs are $15 more, but worth it for the added safety. It's also handy to get the MBVs with position indicators on them so you can glance and see which fermenter is operating at any given time.

I jumped on the thread late but have been reading through; awesome build. Do you have a blog or anything that lays out your process, cost, equipment, etc? Or should I just go slowly through the forum and pick it all out? You've got me sold!
 
I jumped on the thread late but have been reading through; awesome build. Do you have a blog or anything that lays out your process, cost, equipment, etc? Or should I just go slowly through the forum and pick it all out? You've got me sold!

Right here:
http://plasticconical.com/

Haven't had time to finish the controller instructions yet, but everything else is there.
 
Right here:
http://plasticconical.com/

Haven't had time to finish the controller instructions yet, but everything else is there.

This is one of the best DIY projects on this forum. The detailed instructions and inside information on your blog are top notch!

Thank you for putting all this time into illustrating this build. :mug:
 
This is one of the best DIY projects on this forum. The detailed instructions and inside information on your blog are top notch!

Thank you for putting all this time into illustrating this build. :mug:

Glad to help. If you end up building one, let me know if you need clarification on any of the instructions.
 
What would you say this project cost you, total? I went thru all the parts but was having trouble trying to ballpark a number. Just curious how far my money will go if I start now.

Probably around $2k-$2500. You could cut the price significantly by getting rid of the tri-clover fittings though.
 
You did an amazing job on this project and the website is very helpful too! Waiting for the final instructions on there for the controller. A suggestion would also be a price / parts list if you could on there.

Again great job.

Matt
 
You did an amazing job on this project and the website is very helpful too! Waiting for the final instructions on there for the controller. A suggestion would also be a price / parts list if you could on there.

Again great job.

Matt

Glad to hear it's useful. Between grad school and work I haven't had a ton of time to work on the website lately. I just finished the first part of the controller page though. Hopefully, I'll get some time to draw up wiring diagrams in the near future.
 
Great DIY and have a question about what you consider you max temp to be...reason I ask is I do some saisons and they require higher temps and am thinking of doing a separate tank with a heater for that purpose as I don't see anyway to incorporate a heater into this neat setup...probably wouldn't make sense anyway....your thoughts??
 
Great DIY and have a question about what you consider you max temp to be...reason I ask is I do some saisons and they require higher temps and am thinking of doing a separate tank with a heater for that purpose as I don't see anyway to incorporate a heater into this neat setup...probably wouldn't make sense anyway....your thoughts??

You can set it as high as you want really. The only constraint at the moment is it won't go above ambient temp + however much heat the yeast puts out. There is a way to add a heater though. The controller I built actually has everything wired for a heater at the moment .

During the build out, I ran in to an issue that you couldn't associate more than 6 outputs with temp probes. So, I couldn't run a heater. I had posted a question about it on the ECC forum and they pointed out a workaround to get it working. It's not the most elegant solution as it involves changing various states to heat, but it should work.

I haven't gotten around to trying it out yet as it's the middle of summer and ambient temps haven't dropped that low, but it's in the long range plans for probably some time around December when work usually slows down and I get a break from grad school.
 
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