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General Category => Kegging and Bottling => Topic started by: Andor on April 20, 2017, 02:32:42 PM

Title: Closed vs under pressure transfer
Post by: Andor on April 20, 2017, 02:32:42 PM
I recently got an ss brewtech brew bucket which will allow me to rack from valve to liquid out of purged keg, I'm calling that a closed transfer correct me if I'm wrong. The brew bucket can be set up to be pushed with 2-2.5 psi. What is the benefit to doing that over using gravity for a closed transfer?
Title: Re: Closed vs under pressure transfer
Post by: Stevie on April 20, 2017, 02:46:53 PM
Replacing head space with co2 is the biggest benefit. Second is the ability to transfer without needing to lift the fermenter.
Title: Re: Closed vs under pressure transfer
Post by: hopfenundmalz on April 20, 2017, 03:01:51 PM
Decreased time is also a benefit. You are pushing the beer. 2 PSI is like having another 55 inches of beer on top of your beer.
Title: Re: Closed vs under pressure transfer
Post by: blatz on April 20, 2017, 03:22:08 PM
what is the difference between 'closed' and 'under pressure' transfer?

I now use CO2 to push beer into a purged, sealed keg with a spunding valve on the gas post.  would this be considered closed or just under pressure?

+1 to stevie and hopfenundmalz comments. 
Title: Re: Closed vs under pressure transfer
Post by: Iliff Ave on April 20, 2017, 03:40:58 PM
Ha! Seems we are in the same boat.
Title: Re: Closed vs under pressure transfer
Post by: Andor on April 20, 2017, 05:30:50 PM
what is the difference between 'closed' and 'under pressure' transfer?

I now use CO2 to push beer into a purged, sealed keg with a spunding valve on the gas post.  would this be considered closed or just under pressure?

+1 to stevie and hopfenundmalz comments.

Sorry if I used wrong terms.  This is new territory for me. Closed to me is minus racking cane into keg post I suppose. Under pressure is using co2 with the "closed transfer". Please correct me if I've got it wrong
Title: Re: Closed vs under pressure transfer
Post by: juggabrew303 on April 20, 2017, 07:53:23 PM
what is the difference between 'closed' and 'under pressure' transfer?

I now use CO2 to push beer into a purged, sealed keg with a spunding valve on the gas post.  would this be considered closed or just under pressure?

+1 to stevie and hopfenundmalz comments.

Sorry if I used wrong terms.  This is new territory for me. Closed to me is minus racking cane into keg post I suppose. Under pressure is using co2 with the "closed transfer". Please correct me if I've got it wrong
To me, I assume closed and transferred under pressure to be the same.  If you're transferring in a closed system with out using pressure to push out the beer, there would be a vacuum on the vessel and you'd have poor drainage.  I have a plastic bubbler and drain from bottom and it will suck the sides in if I didn't pop the air lock off.  Hope I'm answering your question...


Sent from my iPhone using Tapatalk
Title: Re: Closed vs under pressure transfer
Post by: mabrungard on April 20, 2017, 08:31:51 PM
I recently modified my Blichmann conical to include a bulkhead-mounted, Corny gas-in post so that I can add CO2 to the fermenter during the closed transfer to keg. Using my 5 lb CO2 cylinder, its a piece of cake to dial up a trickle of CO2 to keep the blow off from sucking air into the fermenter.

Several years ago, I changed the air-lock on this fermenter to a blow-off tube inserted into a clear tube. So I can anywhere from a fraction of an inch to over a foot of water column pressure inside my fermenter. The side benefit of that change is that it takes a much larger volume change inside my fermenter to cause air to be sucked into the fermenter. As you know, it only takes a teeny volume change for the typical air-lock to suck air. So if you haven't done this, converting to a blow-off tube is a really good thing to do for preventing air ingress to your fermenter headspace.
Title: Re: Closed vs under pressure transfer
Post by: macbrews on April 20, 2017, 09:00:06 PM
I have a cask breather that I use for my cask conditioned ales (don't tell CAMRA). I can hook that up to cold crash any of my fermenters to prevent air entrainment. I can also use it to gravity transfer beer into a keg as long as there is a spigot.  Works well.


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Title: Re: Closed vs under pressure transfer
Post by: mabrungard on April 21, 2017, 12:23:35 AM
Since Paul wants to see a pic of what I was talking about, I've attached a view.

(http://i1146.photobucket.com/albums/o521/mabrungard/IMG_1080_zpsdjowyf7t.jpg)

The clear tube is a protective cover for a fluorescent bulb with a 1.5" (I think) PVC cap that is Gooped onto the tube. The blow off tube is regular vinyl tubing and it is plumbed into the rubber stopper with a 90 degree 1/2" PEX fitting.  I've used velcro straps to fasten the tube to the leg of the conical.

It works well enough and was cheap.
Title: Re: Closed vs under pressure transfer
Post by: Andor on April 21, 2017, 12:59:54 AM
what is the difference between 'closed' and 'under pressure' transfer?

I now use CO2 to push beer into a purged, sealed keg with a spunding valve on the gas post.  would this be considered closed or just under pressure?

+1 to stevie and hopfenundmalz comments.

Sorry if I used wrong terms.  This is new territory for me. Closed to me is minus racking cane into keg post I suppose. Under pressure is using co2 with the "closed transfer". Please correct me if I've got it wrong
To me, I assume closed and transferred under pressure to be the same.  If you're transferring in a closed system with out using pressure to push out the beer, there would be a vacuum on the vessel and you'd have poor drainage.  I have a plastic bubbler and drain from bottom and it will suck the sides in if I didn't pop the air lock off.  Hope I'm answering your question...


Sent from my iPhone using Tapatalk

Ah I see. I was using "closed transfer" incorrectly as I assumed the keg relief would have to be open. I see that is also where co2 pressure come in. Thanks man
Title: Re: Closed vs under pressure transfer
Post by: narcout on April 23, 2017, 12:43:51 AM
I've always thought of a closed transfer as being where the CO2 in the purged keg flows back into the fermentor.

(http://i240.photobucket.com/albums/ff164/narcout/transfer.jpg) (http://s240.photobucket.com/user/narcout/media/transfer.jpg.html)

As opposed to a transfer under pressure, where additional CO2 is being pumped into the fermentor to push beer into the serving keg where it is then vented

(http://i240.photobucket.com/albums/ff164/narcout/IMG_0789.jpg) (http://s240.photobucket.com/user/narcout/media/IMG_0789.jpg.html)
Title: Re: Closed vs under pressure transfer
Post by: Pricelessbrewing on April 23, 2017, 03:27:17 AM
Since Paul wants to see a pic of what I was talking about, I've attached a view.

(http://i1146.photobucket.com/albums/o521/mabrungard/IMG_1080_zpsdjowyf7t.jpg)

The clear tube is a protective cover for a fluorescent bulb with a 1.5" (I think) PVC cap that is Gooped onto the tube. The blow off tube is regular vinyl tubing and it is plumbed into the rubber stopper with a 90 degree 1/2" PEX fitting.  I've used velcro straps to fasten the tube to the leg of the conical.

It works well enough and was cheap.

That is very interesting Martin.

Might have to consider doing this until I get a spunding valve. I ferment in kegs, so hooking a blowoff tube with a tall column would be pretty easy. I mean I could just hook a gas out blow off tube to another kegs IN dip tube and get an immediate blow off tube of several feet of column if desired...
Title: Re: Closed vs under pressure transfer
Post by: brewinhard on April 23, 2017, 07:03:59 PM
I've always thought of a closed transfer as being where the CO2 in the purged keg flows back into the fermentor.

(http://i240.photobucket.com/albums/ff164/narcout/transfer.jpg) (http://s240.photobucket.com/user/narcout/media/transfer.jpg.html)

As opposed to a transfer under pressure, where additional CO2 is being pumped into the fermentor to push beer into the serving keg where it is then vented

(http://i240.photobucket.com/albums/ff164/narcout/IMG_0789.jpg) (http://s240.photobucket.com/user/narcout/media/IMG_0789.jpg.html)

Narcout-

I believe you are correct in stating this. I have always had trouble keeping my flow going under a true closed transfer. I think it is because I ferment in glass carboys and my beer flows out my racking cane through a carboy hood instead of having a "drain" valve on the bottom of my fermenter like your brewbucket does.
Title: Re: Closed vs under pressure transfer
Post by: blatz on April 24, 2017, 05:19:24 PM
thanks for explaining Narcout!  now I get it.  I presume flow will start as soon as you hook up the QD to the gas in post (which is attached at the other end to the top of the fermenter)?

martin - dumb question, I don't understand what purpose the tube is serving?  do you fill it with CO2?  how is it different than the other ambient air?
Title: Re: Closed vs under pressure transfer
Post by: brandonmmm on April 24, 2017, 06:11:40 PM
I've always thought of a closed transfer as being where the CO2 in the purged keg flows back into the fermentor.

(http://i240.photobucket.com/albums/ff164/narcout/transfer.jpg) (http://s240.photobucket.com/user/narcout/media/transfer.jpg.html)

Thank you for the informative post!

Are you able to cold crash your Brewbucket under CO2 pressure with that ball-lock adapter installed?

I'm looking for a way to cold crash in my Brewbucket without introducing oxygen...
Title: Re: Closed vs under pressure transfer
Post by: mabrungard on April 24, 2017, 08:41:09 PM
martin - dumb question, I don't understand what purpose the tube is serving?  do you fill it with CO2?  how is it different than the other ambient air?

The tube is a regular blow-off. Its advantage is that it takes a lot of internal volume change to actually suck back air into the fermenter.

There is a gas-in corny post fitted onto the top of the fermenter. During lagering temp step reductions and during beer transfer, I supply CO2 into the fermenter via tank and regulator. You can just barely see the corny post in the picture I posted.
Title: Re: Closed vs under pressure transfer
Post by: narcout on April 24, 2017, 10:29:58 PM
I presume flow will start as soon as you hook up the QD to the gas in post (which is attached at the other end to the top of the fermenter)?

It's been a while since I've done it (having switched back to transferring under pressure), but I think I hooked up the gas tubing first, then the liquid tubing, then just opened up the ball valve to start the flow.

Are you able to cold crash your Brewbucket under CO2 pressure with that ball-lock adapter installed?

Yes.  In my experience the Brewbucket will hold 3-4 PSI before gas starts leaking out under the lid.  It's also been my experience that it can hold a vacuum.  When I cold crash, I pump a few PSI of CO2 into it first, then crash.  Before you rack, you need to remember to pump more CO2 in to break the vacuum, otherwise you'll suck in a bunch of air when you open the ball valve.

This is how I attached the gas post (though I think some of the parts links are no longer valid): https://www.homebrewersassociation.org/forum/index.php?topic=20241.0

I've been told by another Brewbucket user that this part also fits: http://www.ebay.ca/itm/232147603644

Though you can't swap between that and a regular airlock or blowoff tube without removing the lid like you can with the stopper assembly.  You'd attach a gas disconnect with some tubing that runs into a jar of sanitizer.  My only concern with that would be the potential for clogging if you had a lot of blowoff.
Title: Re: Closed vs under pressure transfer
Post by: HoosierBrew on April 24, 2017, 10:48:43 PM
I presume flow will start as soon as you hook up the QD to the gas in post (which is attached at the other end to the top of the fermenter)?

It's been a while since I've done it (having switched back to transferring under pressure), but I think I hooked up the gas tubing first, then the liquid tubing, then just opened up the ball valve to start the flow.

Are you able to cold crash your Brewbucket under CO2 pressure with that ball-lock adapter installed?

Yes.  In my experience the Brewbucket will hold 3-4 PSI before gas starts leaking out under the lid.  It's also been my experience that it can hold a vacuum.  When I cold crash, I pump a few PSI of CO2 into it first, then crash.  Before you rack, you need to remember to pump more CO2 in to break the vacuum, otherwise you'll suck in a bunch of air when you open the ball valve.

This is how I attached the gas post (though I think some of the parts links are no longer valid): https://www.homebrewersassociation.org/forum/index.php?topic=20241.0

I've been told by another Brewbucket user that this part also fits: http://www.ebay.ca/itm/232147603644

Though you can't swap between that and a regular airlock or blowoff tube without removing the lid like you can with the stopper assembly.  You'd attach a gas disconnect with some tubing that runs into a jar of sanitizer.  My only concern with that would be the potential for clogging if you had a lot of blowoff.



Out of curiosity, what made you decide to go back to transferring under pressure - transfer time? 
Title: Re: Closed vs under pressure transfer
Post by: narcout on April 24, 2017, 11:06:21 PM
Out of curiosity, what made you decide to go back to transferring under pressure - transfer time?

There would be the occasional clog, and I thought racking under a bit of pressure would help.  Turns out I was using a bad liquid QD (manufacturing defect resulting in low flow).

It would probably work fine now that I have a new QD, but I've stuck with racking under pressure, probably just out of habit.   

I've also started using my 10 gallon corny keg fermentor again, which requires pressure.
Title: Re: Closed vs under pressure transfer
Post by: HoosierBrew on April 24, 2017, 11:30:48 PM
Out of curiosity, what made you decide to go back to transferring under pressure - transfer time?

There would be the occasional clog, and I thought racking under a bit of pressure would help.  Turns out I was using a bad liquid QD (manufacturing defect resulting in low flow).

It would probably work fine now that I have a new QD, but I've stuck with racking under pressure, probably just out of habit.   

I've also started using my 10 gallon corny keg fermentor again, which requires pressure.


Cool, thanks.
Title: Re: Closed vs under pressure transfer
Post by: brandonmmm on December 23, 2017, 08:39:39 PM

I've been told by another Brewbucket user that this part also fits: http://www.ebay.ca/itm/232147603644


I wanted to circle back around on this thread just to say that this part didn't fit my brew bucket. It's real close, but I wouldn't trust it as is to hold a seal. I plan on picking up thicker orings because it's that close.

Hope this helps someone!