DIY glycol tank idea.

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Jako

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So last night I was thinking a bit while looking at a new mini fridge I plan to modify into a fermenting chamber.

Currently I have a SS brewtech 7G conical that I drilled and added a chilling coil similar as to what you would find on the brew master edition.

I also plan on using kegs to pressure ferment 10G batches. The kegs will be fermented in my "fermenting" chamber.

So to my thoughts. At the top of the mini fridge is the Freezer that you would normally find in most. What if a tank was made and filled with glycol that my SS brewtech pump would cycle to chill my conical?

The idea is rough but I haven't seen this type of set up. I have even thought of just making a large tank and setting the fridge low and just running cooling lines to modified kegs or more fermenters.
 

RedRyderr

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Following this thread! I had a similar idea of using my old chest freezer to keep a container of glycol chilled, then pump that through the conical.
 

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I recall someone had a thread here where they modified a dorm fridge to hold/chill the glycol. They essentially carefully bent the freezer portion downward to the fridge and filled the fridge with glycol. If I can find the post again, I'll update my post.
 
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Jako

Jako

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how hard would it be to bend the glycol tubes that chill the freezer element? my first thought it would just kink almost instantly. or even more fun bust and shoot pressurized glycol all over.

i would add a fan to help keep the air moving around the tank. i have a few ideas i am tossing around. one would be a counterflow chiller type idea smaller space and more efficient.

going to take a look at the thread you posted.
 
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i do as well. What really has me thinking is what type of life you would get out of the fridge. I found a almost one one locally for 20$ if it last a year its a win win. if the think had some type of insulation that would currently help.
 

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You need the evaporator of the freezer inside the glycol, otherwise the heat exchange with air in between will be very bad.
A frien of me, refrigerator expert, replace the evaporetor all together by a copper tube around the fermenter and insulated the whole thing around. With a 1/5 hp unit it cold ok 200L.
 

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Why not just do the air conditioner and cooler route? I've got 2 I built that are 18,000btu (1 ton ) not that you would need that big of an air conditioner for a couple 7 gallon conicals. Facebook marketplace $50 a piece for the 18,000btu units (5,000btu are even cheaper) and coolers $10 each. Granted there is other stuff to buy like temp controllers, pumps, tubing, insulation, valves, and what not but you would be buying all that anyway.
 
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Jako

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You need the evaporator of the freezer inside the glycol, otherwise the heat exchange with air in between will be very bad.
A frien of me, refrigerator expert, replace the evaporetor all together by a copper tube around the fermenter and insulated the whole thing around. With a 1/5 hp unit it cold ok 200L.
that sounds very interesting, how is he able to move the fermenter around. i would love to see this if you are able to take pictures some time.
 
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Why not just do the air conditioner and cooler route? I've got 2 I built that are 18,000btu (1 ton ) not that you would need that big of an air conditioner for a couple 7 gallon conicals. Facebook marketplace $50 a piece for the 18,000btu units (5,000btu are even cheaper) and coolers $10 each. Granted there is other stuff to buy like temp controllers, pumps, tubing, insulation, valves, and what not but you would be buying all that anyway.
i think its more of what i have on hand. i have thought about AC unit builds but haven't put a whole lot of thought into this.

my plan from the start was to just have a fermenting chamber under a large workbench that i am building in my brew room. like all things you tend to get more ideas or over think things. even putting a large tank of water more ore less in a fridge and using that water to cycle like a glycol unit would work. wouldn't get nearly as cold but for me i have no need to cold crash.
 

superiorsat

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"but for me i have no need to cold crash." I think you might be good with your idea then. Maintaining temp at a 60-70F level would not require a ton of heat transfer to accomplish this.
 
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"but for me i have no need to cold crash." I think you might be good with your idea then. Maintaining temp at a 60-70F level would not require a ton of heat transfer to accomplish this.
thought about this for a night or two now. I think you are right it would work well for exactly how i intend to use it.
 

Lalo_uy

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that is very cool! will Glycol react negatively with copper? i feel like this is a stupid question.
I see plenty of chiller with a copper coil in a tank with water glycol mix with no problem.
Any way the system I talk about has no glycol. The freezing gas goes in the copper coil.
 

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Unless you're already an HVAC tech with the tools and knowledge, you're not going to be replumbing the cooling lines into copper coils. It requires recharging the compression system with coolant. As others said, a tank inside a minifridge is not going to provide the heat exchange you need unless you're only planning to keep the fermenter 10F or less below ambient.
 
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Is it just because a mini fridge has a small glycol capacity to begin with? Starting to understand I think.

Am I making a big mistake if I plan to turn one into a fermenting chamber?
 
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I see plenty of chiller with a copper coil in a tank with water glycol mix with no problem.
Any way the system I talk about has no glycol. The freezing gas goes in the copper coil.
Whats the difference between each system? Would a gas chilled coil system chill the glycol?
 
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Appreciate all the experience and knowledge. I love to learn. So I apologize all the brain picking
 
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I just finished a glycol chiller build (based upon the ideas of others of course!). A 5000 BTU A/C unit, a cooler, and glycol/H2Osolution. Inside are the pumps for the three fermenter's Anvil cooling systems. It chilled from ambient temp (84F) to 50F in about 10-15 minutes. Once I start fermenting again, I am sure it will need to run a little more often, but it's holding temp really well right now. Some stuff I had, some stuff I bought used, some stuff I bought new, but here is an estimate compared to a new Name-Brand Glycol Chiller at about $1,000 (not including any cooling hardware your fermenters might need):

A/C unit (new)-$160
Cooler-Old, Used, Basically Free
Glycol-$50/5 gallons, I used 2.5G with 5G of Distilled H2O-$6
Three Anvil Cooling Systems @ ~$125per=$375
Power Strip-Had It
Wood and Foam Insulation-$50
Neoprene (I am going to make insulating sleeves for the two SS fermenters I have that don't have one)-$25
Drill Bit for Tapping the SS Brewbucket Lids to allow for the Anvil Cooling Systems-$10
Inkbird for the A/C unit-Used, $25.

Approximately $701.

I looked at my plan as a serious option, since the cooling system alone for an SS Brewbucket is $256 (x2=$500+), plus Chiller($1000+), etc.

IMG_1234.JPG
 
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Jako

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this is very cool. i would love to see inside the cooler and the coils
 
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It's pretty simple because I set up each fermenter with its own temp controller and pump. I have seen more complicated systems, which if one is an engineer, are probably cheaper to set up, but I'm a theologian, so....
IMG_1232.JPG
 

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It's pretty simple because I set up each fermenter with its own temp controller and pump. I have seen more complicated systems, which if one is an engineer, are probably cheaper to set up, but I'm a theologian, so....
I have a bit of a Frankencooler myself so I wonder if you could tell me a) what you used for the gaskets on the cooling lines going through the lid and b) where you plan to get the neoprene?
 
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The gaskets in the lid for the cooling hoses are just from the LHBS. They are the standard ones for a plastic bucket fermenter.

I got the neoprene at Joann’s fabrics. Lots of colors to choose from if you care; I’m a basic black kinda guy myself.
 
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Suck's tomorrow I find out the real damage.

Well I need surgery and a new job. Turns out punching someone at work is against the rules. Regardless of the situation. Lesson learned report bullying and have it physically documented because management will forget you said anything once you stick up for yourself.
 

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After reading the advice above a few times over and looking at that other build. I think I could set this up to maintain fermenting Temps. I just don't think it's worth destroying a fridge even if it cost me 20$ it's practically new but I don't think I would ever be satisfied with the final results. Wife was going to buy me a new fermenter or bed cover for my truck for my birthday. I might just buy a chiller and eventually get that shiny unitank once I can maintain Temps reliability.

Big sigh. I did learn a ton from the help so thank you everyone. Now what should I do with this fridge? Basement kegerator?
 

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Is it just because a mini fridge has a small glycol capacity to begin with? Starting to understand I think.

Am I making a big mistake if I plan to turn one into a fermenting chamber?
Edit: apparently I missed the entire second page of this thread before commenting.. My bad.

Original comment:

Mini fridges don't have glycol they have freon which is a refrigerant.

Using a mini fridge as a fermentation chamber works well because you have an insulated volume inside the chamber that you're chilling and that's it.

The problem with your glycol tank idea is that you're using the mini fridge to chill the glycol, which is then circulated through a conical that is absorbing heat from the environment at a pretty high rate. So effectively, you would be trying to use your mini fridge to chill the entire room in a very inefficient way. I also have a friend that tried that with a full sized freezer and a keg full of glycol and he couldn't chill his fermenter below 50F

You need a chiller that can remove heat from your beer at a faster rate than it can absorb heat from the environment and keep up with the glycol temp rise.

I recommend the AC unit build. Even if you can't find one on Facebook marketplace you can buy a new one for $120 at Lowe's and a cheap cooler at Walmart. It's probably your most cost effective (and actually effective) option
 
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I started with a mini-fridge as a dedicated brewing fridge: yeast cultures, hops, pre-crushed grain (when I was doing extract brews). Now most of that is stored in my keezer at 36F with 3 kegs. This hobby can rapidly deplete a wallet as you move upwards and onwards.

I forced myself to sell off the items from one hobby to pay for this one. By keeping myself on a zero-sum budget I was able to spend more time planning the projects before I invested the time and money. Before this glycol build, I was going to make an 8'x3'x3' enclosed fermentation chamber/worktable. I am glad I didn't, as I think the setup I have is better use of space, energy, and cash resources. But it did take almost a year longer to pull it together than the other idea.

This is the keezer; the only mod is the collar to allow for holes for CO2 and temp control, and space above the kegs for the hoses, etc. When the space isn't so tight, I want to put stainless taps in the front, but can't yet. Everyone would run into them constantly, knocking them on and off, it would just be a mess.

Good luck on your projects!
Keezer Exterior.JPG
Keezer Interior 2021.JPG
 
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Jako

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Edit: apparently I missed the entire second page of this thread before commenting.. My bad.

Original comment:

Mini fridges don't have glycol they have freon which is a refrigerant.

Using a mini fridge as a fermentation chamber works well because you have an insulated volume inside the chamber that you're chilling and that's it.

The problem with your glycol tank idea is that you're using the mini fridge to chill the glycol, which is then circulated through a conical that is absorbing heat from the environment at a pretty high rate. So effectively, you would be trying to use your mini fridge to chill the entire room in a very inefficient way. I also have a friend that tried that with a full sized freezer and a keg full of glycol and he couldn't chill his fermenter below 50F

You need a chiller that can remove heat from your beer at a faster rate than it can absorb heat from the environment and keep up with the glycol temp rise.

I recommend the AC unit build. Even if you can't find one on Facebook marketplace you can buy a new one for $120 at Lowe's and a cheap cooler at Walmart. It's probably your most cost effective (and actually effective) option
I stared looking for AC units. High hopes since fall is around the corner.

I decided to order a fermenter with hopes of being able to find an AC unit and after my surgery able enough to brew and get back to normal.
I started with a mini-fridge as a dedicated brewing fridge: yeast cultures, hops, pre-crushed grain (when I was doing extract brews). Now most of that is stored in my keezer at 36F with 3 kegs. This hobby can rapidly deplete a wallet as you move upwards and onwards.

I forced myself to sell off the items from one hobby to pay for this one. By keeping myself on a zero-sum budget I was able to spend more time planning the projects before I invested the time and money. Before this glycol build, I was going to make an 8'x3'x3' enclosed fermentation chamber/worktable. I am glad I didn't, as I think the setup I have is better use of space, energy, and cash resources. But it did take almost a year longer to pull it together than the other idea.

This is the keezer; the only mod is the collar to allow for holes for CO2 and temp control, and space above the kegs for the hoses, etc. When the space isn't so tight, I want to put stainless taps in the front, but can't yet. Everyone would run into them constantly, knocking them on and off, it would just be a mess.

Good luck on your projects!
View attachment 739162View attachment 739163
That freezer set up looks awesome! Thank you for the great advice. My current project was trying to play video games with my 4 year old. It ended with me annoyed and Mario dying over and over.
 
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Jako

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I am going to look at a 10k BTU AC unit this evening. The guy has two for sale one is 5k and 10k. He said the 10k unit will stop cooling when it gets to hot. Sounds like it could be dirty or the compressor was over worked and kicks off.

Is this a fixable issue?
 
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Small update. Interesting day in utah. Flooding on a large scale. My neighborhood took a massive hit lots of flooded basements. I will never understand walk out basements.

I ended up digging into the AC unit. Took it apart almost part by part to clean it up. It had so much dirt and junk in general. Debating adding some paint on the fan shroud and AC base plate.
 

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