DIY Cold Crash Protector

[@BobbyFromNJ]

Inventor (I use that term very lightly) of the Cold Crash Guardian here. I just have a slight correction on something you said about the required volume. We started with a 1 gallon bladder and myself and other customers have found it to be inadequate volume in some cases. If you just use it for the initial crash and don't leave the fermenter sitting cold for too long, a gallon is enough .We had to upgrade to the 2.5 gallon after enough reports of running out of gas and collapsing flexible fermenters (or in some cases sucking air in). 1/2 or 1 gallon may work for many applications, but just wanted to clarify that larger is better if you can get it.

[@joshuapinter]

One of the best comments I’ve read on KZbin. Humble and providing value. Love it. Is this due to the CO2 re uptake from the beer as it is now colder and reaches equilibrium? As a Canadian in Ontario, do you know where I can buy your product sir? Thanks! Joshua

[@rdavidw68]

@@joshuapinter Generally speaking, gasses and liquids contract or get smaller as they get colder - creating a vacuum in the fermenter. There will also be a nominal amount of CO2 uptake during cold crashing.

[@dyyddson]

@@joshuapinter it takes like two weeks to reach proper equilibrium, the process is slow. If you crash for a shorter duration only, like a day or two, there is less need for such volumes. Suckback happens because the gas inside the fermentor shrinks as it cools, and also because of in cooler liquid, co2 has higher solubility. It goes more into the beer. Two effects. The latter one is slower and takes time to reach equilibrium.

[@stewbeats3171]

Is it just during the drop in temp that creates the vacuum, once it’s at cold crash temp you should be able to switch back to blow off tube right? So does that mean only variable that would matter would be the amount of time it takes for you to drop temp and how much temp you are dropping?

[@BobbyFromNJ]

@@stewbeats3171 No, once the beer gets cold it will also start absorbing additional CO2 from the headspace. It's not intuitive at all but it takes a bunch of volume out of the bladder on the initial cool down but it continues to shrink over say a week in the cold.

[@TheBruSho]

Genius build man, always been curious about how something like this works and nice to see its not hard to make

[@CityscapeBrewing]

Thanks man! Works great for Hazy IPAs! I usually cold crash in a keg but certain styles I crash first and this works great! 🍻

[@AaronHorwill]

Hi great video! I brought these parts however i was unable to locate the cap and the thread extender to overcome the cap not fitting issue. Your links don't go to these parts. Are you able to update for links to the thread cap and the thread adapter. Much appreciated. thanks!

[@CityscapeBrewing]

Thanks for letting me know those were not on there! I updated the video description to include them now, but here are the links if that is easier for you! 3/4 threaded coupling (3/4 threaded to 3/4 threaded): amzn.to/4fDVd2e and 3/4 male PVC plug: amzn.to/4fDV6Um

[@milkcoffee4124]

If there already is a one-way check valve, do i still need the co2 captured ballon. When it Suck Back the valve will stop any fluid or oxygen coming through. No offend buddy i just want to stick with the cheapest gear. Cheers mate.

[@CityscapeBrewing]

Good question but no, because when you take off the tubing, or go to transfer it, it will suck oxygen into the tank because of the reverse pressure. The bag keeps the pressure even.

[@milkcoffee4124]

Thank you great infomation. One more question that is i normally use blow-off tube and when bottling i dont take off the tube but fill it with a little sanitizer, allow a bit oxygen being suck in to let beer flow out the spigot (basic pressure stuff). So its my first time using these coldcrashguardian, would i remove this setup and connect the normal tubing when transfer?

[@CityscapeBrewing]

@milkcoffee4124 yes you can but won't have the suck back, so minimum oxygen getting in with the quick change

[@rdavidw68]

Nice vid, thanks for posting. If you connect the bag right after pitching, the oxygen in the fermenter head space will be pushed out first and into your collection bag. CO2 is 1.5 times heavier than air, so if the outlet of your bag is at the bottom, the oxygen will stay in the bag until the bag is deflated. I push aquarium airline tubing into the top of a S style bubblelock, connected to a 5 gallon ziplock bag (punch a small hole near the top of the bag and push the tube in and seal with silicone calk on both sides). I then have another line of tubing on the other top side of the bag running down to a small bottle of water to create back pressure and as a secondary airlock. I connect the empty, sanitized bag at the start of fermentation, since both tubes are at the top of the bag, the oxygen that is pushed out of the top of the fermenter is also pushed out of the full bag and out the water bottle. An avg five gallon batch produces about 20 cubic feet or 150 gallons of CO2. I keep it on when cold crashing and racking to the keg. I can pull the tube out of the water bottle if the 5 gallon bag is completely deflated when doing a sealed transfer to the keg. Whole setup is only two or three bucks and works great. Cheers!

[@CityscapeBrewing]

I don't open the valve until active fermentation is underway for a while. That pushes the oxygen through the tubing into the sanitizer... And doesn't allow oxygen to go into the bag either. Then once the headspace is purged for several days I open the valve and allow the bag to fill up.

[@rdavidw68]

@CityscapeBrewing That works, but it's one more thing you have to schedule to do. Thanks again for posting.

[@curtpick628]

I just use my used ostomy bag 🤣 but of course I sterilize it first😆

[@CityscapeBrewing]

Hahaha. Whatever works! 💯🤣🍻