Partial DIY Fermentation Temp Control Using Cool Zone Cooling Jacket

[Woodbrews]

I'd like to look into glycol as well, since I've had my water reservoir freeze up in my kegerator. Although the my refrigerator's internal thermostat is set to 43F or so, it doesn't really regulate the temperature very well and sometimes it gets way too cold.

With glycol, it may be possible to use a small freezer, instead of a refrigerator or insulated cooler, to house the reservoir. Glycol will handle much colder temperatures without freezing up, so you can bring the coolant temperature down much lower than you could with just water. You'd need to investigate whether the pump will work with glycol and at such low temperatures; if not, then one option might to use an inline pump housed outside of the freezer.

Does anyone know of any sources for propylene glycol? Is it necessary to use food grade propylene glycol?

 

[dmcman73]

I'd like to look into glycol as well, since I've had my water reservoir freeze up in my kegerator. Although the my refrigerator's internal thermostat is set to 43F or so, it doesn't really regulate the temperature very well and sometimes it gets way too cold.

With glycol, it may be possible to use a small freezer, instead of a refrigerator or insulated cooler, to house the reservoir. Glycol will handle much colder temperatures without freezing up, so you can bring the coolant temperature down much lower than you could with just water. You'd need to investigate whether the pump will work with glycol and at such low temperatures; if not, then one option might to use an inline pump housed outside of the freezer.

Does anyone know of any sources for propylene glycol? Is it necessary to use food grade propylene glycol?

The question is though, how fast will the freezer cool the glycol as it's being cycled through a reservoir that s just sitting in it? If you think about it, how long does it take for a bottle of water to chill once it's placed into the fridge/freezer? I could be wrong so hopefully someone on here who has or is doing it this way can chime in.

I believe it will take longer to chill "ambient" than it would if it was being chilled directly (refrigerant coils submerged into the liquid). If I remember correctly, there were a few posts on people taking apart small A/C units so that they can place the cold side coils right into the liquid to chill it faster. I wanted a cleaner look so I purchased a used aquarium chiller, same concept. Water is pumped through a reservoir that is lined with the cold side coils from the reintegration system.

 

[TrickyDick]

Food grade glycol is in case the glycol gets into the beer you won't suffer the toxic effects of something that isn't safe for human consumption, such as ethylene glycol aka antifreeze. I got mine from work for free!

Air is a poor conductor of energy to chill liquids. Rather than using a freezer to chill the coolant solution consider this. You could purchase a picnic cooler (without a drain) into which you submerge the cold-side condenser coil from a small $100 window a/c unit. Get a "dumb" one and use a temp controller such as an STC 1000 to turn the AC unit on or off at your desired temp, and maybe find a way to control the hysteresis to something pretty high to keep it from cycling all the time. It'll chill the glycol in the cooler. This requires a bit of destroying a perfectly good AC unit. You'd only need a very small one to do the trick. This would be more energy efficient in the long run.

How much pressure can the cool zone jackets handle?

For the user with the stainless FTSS through the lid fermentation chiller, can you send me some detailed pics of how that mounts to both inside and outside? Seems like a TC ferrule then some MNPT threads? Is the coil itself threaded or is there a nut or piece of pipe coupler welded on? What's the spacing between the ferrule and the threads? Is there an O ring on the inside or outside of the lid? I'm in the process of contemplating switching my plastic glycol chilled conicals over to stainless and this is a stumbling block for me- how to get a sanitary connection on the inside that is also removable and airtight.


Thanks

TD

 

[jmitchell3]

to answer your question, cool zone jackets will handle 8 psi. http://www.gotta-brew.com/products/cool-zone-cooling-jacket.html

 

[augiedoggy]

I use one of these cool zone jackets for my conical and it brings 10 gallons down from 76 to 66 degrees in less than an hour while uninsulated and in a 78 degree room. The only issue I have with them is for what your buying (basically a modified $20 solar shower) they are costly. and they have already gone up another $10 in price since I ordered mine. (Im cheap I guess but I always look at what im actually buying and the costs involved in production)

I have three more fermenters to control the temps on and will likely go the route of stainless coil inside or copper coils wrapped around the outside just to save some needed $$

They do work well though ... BTW I'm using a glycol chiller with mine. and much more than 8psi although I plan on that dropping very soon when my other fermenters and the solenoid valves are plumbed in to the pump/line.

 

[TrickyDick]

How are you regulating pressure?

 

[9Dave]

I haven't seen many new forums for feedback on the Cool Zone, and a couple point to this one, so I figured I'd post here since those looking for experience with it may check here.

I've had two Cool Zones for a year and a half and have done 33 batches with them. They're great and I'd recommend them. I planned on doing a cold water chamber in my keezer but instead went with a large Xtreme Coleman cooler. It works fine for running both of them at the same time (about 1/3 full with bottles of ice). I have to change them out about every 3 days (though my house rarely gets above high 70's). I do lagers in the winter with them, though it's in my mudroom that often gets down to the 50's. Based on my experience I'm sure I could do them in the summer but I'd likely have to change the ice about once a day and I don't feel like doing that (plus I stockpile them in the winter and pull them out of cold storage as needed).

I've cold crashed once with one of them. The beer was at 66.7. The house was at 67. It took a little over 7 hours to drop to 44F.

What I like most is how good it is at holding temps in a tight range. My friend has one and keeps his beer within a fraction of a degree. I have a wider range since I don't want the heater and pump fighting each other and making me have to change the ice as often. So, for example, I'll set the Cold at 67F and the Heat at 66F and have the differential for both at 0. When the cold kicks on it'll typically drop it to 66.5-66.8F. I've never seen it drop more than 0.8F, so with this set up I'm staying less than 1F (typically within 0.2 to 0.3 change).

The only problem is you can't leave for a few days or slack off on changing the ice. On one lager I didn't change the ice in time and I woke up the next morning to a feedback loop where it was too warm so it kept pumping the water, which was now warmer than the beer. This was slowly raising the temp as the water warmed more. Luckily the timing worked out as a D-rest.

But all in all I love the system and would recommend it.

 

[bisforbrew]

anyone know if the Cool Zone Thermal bag collapsible?

 

[9Dave]

Yes, you can collapse it but it takes a little work, though just a little. It comes with a bottom and side liner that you'd want to remove. The side one velcros into place. But once you take those out I imagine you could get it to store pretty flat, which is how I believe I received it but it's been a while (and I've left them assembled ever since).