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mpcluever

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I've got a 27 gallon conical in a refrigerated box I built for it. When I go to crash cool it, it sucks up whatever liquid was in the airlock. I built this to combat that.



CO2 comes down the hose, into the 1st jar, up the pipe, then down the pipe of the 2nd jar, bubbling up and out.

When I start cooling and everything contracts or I dump trub off the bottom of the conical, it sucks water from the 2nd jar back into the 1st, putting sanitary CO2 back into the conical rather than unfiltered air, or worse, a bunch of sanitizer.

The water level in the 2nd jar is low enough that if it sucks over all the liquid, it won't reach the connection for the hose, so it will just bubble air at that point.

When dumping trub, it sucks water back, but the pressure of the incoming CO2 pushes it all back over into the 2nd jar, resetting itself. Thought maybe someone else might appreciate it.



:rockin:
 

kcmobrewer

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That is awesome, I love it. Any chance you could post a parts list? Obviously it's pretty simple. I'm just not the best on figuring that kind of stuff out.

Planning on getting a conical very soon and would love to have something like this.
 
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mpcluever

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All I did was drill holes in the lids of the canning jars (half gallon). The PVC is currently just pushed together, no glue. Bulkhead gaskets I got from Midwest Supplies to seal the PVC against the lid.

Inside the jars are just Female to Female pipe connectors. There's very short sections of pipe that go through the lid and go into the connections on either side. It's a 90 Street connection off the top to connect the jars with another Female to Female to connect them. Hope that makes sense.
 

kcmobrewer

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That does, thanks. Which gaskets are those? I did a search on midwest looking for something similar but couldn't find them.

Also, I hate to be a bother. But what size PVC is that?
 

dobe12

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I remember someone building something similar to this to collect yeast from primary during active fermentation. A little different setup but the same idea. The first jar collects the yeast, the second jar is the airlock and holds the sanitizer. I've been thinking about building something like this for the purpose of yeast collection.

Nice solution to a problem!

:mug:
 

day_trippr

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Is the lid on the right hand jar vented?

Cheers!
 

killebrew

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Yeah, if you look really close you can see the hole.

I have a question about oxygen exposure with your set up. With CO2 being heavier wouldn't it be better to have the pipe going to the 2nd jar the same height as the pipe coming from the conical? Think of the jar filled with oil (o2) and the conical adding water (CO2). When the water is added to the first jar it will go to the bottom and then out to the 2nd jar before displacing all of the oil (O2). Then when the pressure reverses the oil (O2) in the 1st jar would be sucked back into the fermenter before the water (CO2) thus exposing the deliciousness to oxygen.

Please let me know if I am mistaken with my thinking on this.
 

number40fan

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^^ I believe that you are right, but in order to purge all of the oxygen, but not suck up any water, both tubes in the left jar should be the same height.

It will allow the C02 to settle in the bottom left and push out the O2 into the bottom right, full of water. Then as it sucks back from the right, the water fills the bottom left pushing the CO2 back up the line.

Only draw back is moving the water back to the right jar when starting a new batch.
 
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mpcluever

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I'm using a conical, so if the pipe was not to the bottom in the first jar, when I dump the trub it would suck all or most of the water back to the first jar and be stuck there. With the pipe to the bottom, it will blow that all back to the 2nd jar and reset itself for when I start crash cooling. With 22 gal of beer fermenting, there's so much CO2 blowing through there, I'm not worried about oxygen getting stuck in there.
 
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^^ I believe that you are right, but in order to purge all of the oxygen, but not suck up any water, both tubes in the left jar should be the same height.
Not really. As long as all of the water, when transfered from the right jar to he left jar, is below the top of left jar's inlet (short, left) pipe, it will simply suck air from the right jar. If the water can't reach it, it would suck air back up. The water in the left can't magically "jump" to the pipe.

MC
 

Carlscan26

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The other thing is that gases are not like oil and water - they will mix and reach a point where they're evenly mixed. But with the amount of CO2 being generated you'll effective push out all of the O2.


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dcuccia

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Loved this and made one, thanks for the tip! Used silicone to connect the two, instead of PVC.



Just mentioned this to Larry w/r/t his Catalyst blow-off woes [ame]https://www.youtube.com/watch?v=QfI8kaXfRic[/ame]
 

daphatgrant

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Unfortunately the original pic can't be viewed but I love the model that was made on post 16. I'm new to brewing and left a blow-off tube connected to a mason jar of starsan and sucked up about 8oz into my first ever IPA while cold crashing. I was thinking about switching to just regular air locks but with something like this I can continue to use the blow-offs and not fret about starsan being sucked into the fermenter or unnecessary oxygen being added. Very cool!
 
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mpcluever

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Ya, sorry that original pic isn't working. The pic in #16 is a good representation! Nice work!!
 
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