Can you diy a "dorm freezer" for a cheap glycol for a 5 gallon conical?

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Nate R

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Hi all.
Trying to diy a cheaper glycol system without cutting up a window ac unit. #1 because i am handy but not that handy and #2. I want to use it in the house and swmbo would not go for a compressor of that size kicking on (small house).

I have a spike cf5 with cooling coils.
If i get a 1.1 cu freezer only, figure i can get say about 1 to 2 gallons of glycol/h2o mix in there. If i let it run for a day or two it should get it pretty cold.
Would the little freezer be able to cold crash to say 36 or so? I assume it would be able to keep ale temp at say 68, maybe even lager at 40 to 50 for weeks?

If i got a 3 cu freezer only, was able to get say 3 gallons or so of glycol/h2o, would that increase chances?

I am not an hvac guy. My gut is telling me if this was possible then i would have found more threads on it. I am guessing since basically all i find is window ac builds my idea is not feasible.

Apprecaite any insight here.
Thanks all.
 

OneInTheHand

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My plan was similar to this, haven’t had time to get it done yet. I have a dorm fridge with separate freezer compartment. I drilled two holes in the back and then planned on having an 8”x8” heat exchanger inside the freezer box. Maybe a little fan in there too to move air around. Then use chilled liquid for either fermentation control or to chill a couple kegs.
 

mongoose33

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There's a thread on here somewhere that shows someone putting such a fridge on its side, and reorienting the refrigeration unit so it would remain level to the ground.

I think you can use such a system effectively for maintaining ferm temps, but unlikely that you can crash very low with it. The recovery ability is likely to be low, and that's what you'd need to crash.
 

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Not even saying you can - but the smaller the chiller, the more insulated the fermenter needs to be.

Temperature stability in the fermenter reduces energy demands in on the chiller.

You would probably be better off with a big cooler filled with mostly ice and some water. drain water and add ice as necessary. As long as ice is floating, it is still cold enough.
 
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Nate R

Nate R

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Thanks all. @mongoose33 I know that thread- but it was a small "dorm" style freezer. He moved the compressor, flipped it over, and was able to keep good temps.
After much reading and pondering, I decided to just order a professionally made chiller. I went with the Penguin 1.3hp model- I liked the idea of a small reservoir- less glycol to buy & replace. (I only have a cf5, and may add another 5 down the line, so do not need that much power).

I think the best build I saw was where the guy put the actual chiller plate from a dorm fridge into the bath of glycol/water.
 

mongoose33

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Thanks all. @mongoose33 I know that thread- but it was a small "dorm" style freezer. He moved the compressor, flipped it over, and was able to keep good temps.
After much reading and pondering, I decided to just order a professionally made chiller. I went with the Penguin 1.3hp model- I liked the idea of a small reservoir- less glycol to buy & replace. (I only have a cf5, and may add another 5 down the line, so do not need that much power).

I think the best build I saw was where the guy put the actual chiller plate from a dorm fridge into the bath of glycol/water.

I knew you'd made that choice, was just responding to the other poster.

I didn't mention it (I don't think), but I went through an exploration of trying to keep a glycol reservoir in the freezer of my big ferm chamber. In the end, it actually worked quite well, except I couldn't crash it down below about 40 degrees, maybe 38 with the right ambient conditions.

I thought that the Penguin would be the answer, because of recovery and capacity. It's still a monster, but I can't get the fermenter down below about 38. There's just too much sticking out of the fermenter that act as radiators sucking ambient heat into the fermenter.

Make no mistake: the Penguin is great. It's also compact, and recovery is fabulous.

Someday when I figure out how to cut nice square pieces of 2" foam board I'll build a box around the fermenter and isolate it from ambient that way. I think if I can do that, I'll be able to get it lower. But those pieces need to be square in all orientations, 2' x 4', so still trying to figure out a way. If I had a big area with a large table I could rig up a hot wire to cut it, but I'd need a jig to hold things square....
 

OneInTheHand

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Why not just use small 2'x2' squares to build up your 2'x4' panels? If I had to build a fermentation box I'd build walls out of 2x6 lumber, put fiberglass or roxul in the stud cavities, foam panel on the inside, plywood or drywall on the outside.
 
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Nate R

Nate R

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I knew you'd made that choice, was just responding to the other poster.

I didn't mention it (I don't think), but I went through an exploration of trying to keep a glycol reservoir in the freezer of my big ferm chamber. In the end, it actually worked quite well, except I couldn't crash it down below about 40 degrees, maybe 38 with the right ambient conditions.

I thought that the Penguin would be the answer, because of recovery and capacity. It's still a monster, but I can't get the fermenter down below about 38. There's just too much sticking out of the fermenter that act as radiators sucking ambient heat into the fermenter.

Make no mistake: the Penguin is great. It's also compact, and recovery is fabulous.

Someday when I figure out how to cut nice square pieces of 2" foam board I'll build a box around the fermenter and isolate it from ambient that way. I think if I can do that, I'll be able to get it lower. But those pieces need to be square in all orientations, 2' x 4', so still trying to figure out a way. If I had a big area with a large table I could rig up a hot wire to cut it, but I'd need a jig to hold things square....
Every time I have attempted to use foam... I have little remnants in the house for weeks (yes, I cut outside), and my recycle/trash bin is full of cut up, jagged, worthless foam. Now of course this speaks to my craftsmanship more than the product, but still... I can cut a piece of wood almost straight.
 
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Nate R

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So quick update if anybody cares:
Got a FedEx tracker code in 24 hours- so a 1 day turn-around time (they say 3 on website).
Also, submitted a question on their website today about what type of Glycol (see below). That response was under 2 hours... so all in all- very happy so far!

Here it is as FYI:
I asked if I need to use inhibited glycol or can just use "regular" glycol.

"Inhibited glycol is the stuff you are talking about, and it's not necessary for cold applications. It's used in systems for building heating/cooling, and it's the heating part that can break glycol down into glycolic acid if it's not inhibited. Your average brewing setup will not run into any problems using standard polypropylene glycol." That's direct from Penguin, so I feel safe with just regular glycol.
 

mongoose33

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Why not just use small 2'x2' squares to build up your 2'x4' panels? If I had to build a fermentation box I'd build walls out of 2x6 lumber, put fiberglass or roxul in the stud cavities, foam panel on the inside, plywood or drywall on the outside.

Where do I get those? I'd do it if I could find them and they weren't too expensive.

Part of the issue is space. What do I do with it when I'm not cooling a fermenter? I have limited space in my garage; I figured I could take apart foamboard and strap it together and suspend it from the ceiling.
 

mongoose33

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Every time I have attempted to use foam... I have little remnants in the house for weeks (yes, I cut outside), and my recycle/trash bin is full of cut up, jagged, worthless foam. Now of course this speaks to my craftsmanship more than the product, but still... I can cut a piece of wood almost straight.

That's why I'd want to use a hot wire instead of a saw. I want these pieces to be perfectly square (or as close as possible) so the sides fit together snugly, essentially, airtight.
 

backwardsblade

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Yes you can, I have modded mine consistent with a “Metzen” glycol chiller. It is paired with a flex+ and I can control (cool/heat), cold crash, and use it as a functional brite (with assoc. carb stone). Have a pic of it here.
 

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