First time closed CO2 Transfer

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And I didn't blow up the glass carboy! I will never use an autosiphon again!:ban::mug::rockin:

Excellent! I do closed loop transfers to keg from my 7G Ss BrewBuckets. Very slow using low psi, but the results pay for the trouble with fresh beer that has no oxygen exposure.
 
Excellent! I do closed loop transfers to keg from my 7G Ss BrewBuckets. Very slow using low psi, but the results pay for the trouble with fresh beer that has no oxygen exposure.

http://www.********************/brewing-methods/fermenter-to-keg-spunding/

No need to use co2 to push. Fill keg with sanitizer, push out with co2. Then hook up the gas in to fermenter in, and fermenter out to liquid out.
 
http://www.********************/brewing-methods/fermenter-to-keg-spunding/

No need to use co2 to push. Fill keg with sanitizer, push out with co2. Then hook up the gas in to fermenter in, and fermenter out to liquid out.

This is KINDA what I did, just without the sanitizer push. I swished about a gallon of sanitizer in the keg so that it covered everything, then drained. At this point, I hooked up the CO2 and pressurized and purged the keg about 10 times. I hooked up a gas connector on the IN side and the fermenter to the OUT post. I just liked using the CO2 better than gravity. Picking the fermenter up to counter height sucks!
 
My 1st attempt should happen tonight as long as Amazon shipping is on time and all my new parts match all the stuff I had on hand already. Hopefully all goes well :mug:
 
My 1st attempt should happen tonight as long as Amazon shipping is on time and all my new parts match all the stuff I had on hand already. Hopefully all goes well :mug:

If you are using glass, just keep it at 3 psi......and stand behind a wall!:D
 
I did manage to pop the bung off the top once. Scared the crap out of me. I was running at 1-2 psi. I think next time I'll have the carboy on a table with the keg on the floor so gravity can work for me.
 
2-3 psi is way overkill.
A human can generate ~ 1.5 psi, and I would not put more pressure on a carboy than that.

Gravity plays a very important in that regard. All you need CO2 to do is push the beer "over the hump" and then let gravity take over, reducing the CO2 pressure to just enough to keep a vacuum from forming in the carboy which would slow the gravity flow.

Obviously, like nearly every friggin' thing in brewing, patience is key...

Cheers!
 
I recently attempted to transfer from primary to a corny keg, but ran into some issues! My big mouth bubbler was full of Co2, spiggot opened, and it just didn't wanna go into the keg. Could this be due to not purging the keg before hand? I don't think my drop line was clogged because its been find with the now oxidized IPA lol
 
Note that after starting the siphon, if you equalize the head pressure between the fermenter and the keg, it'll continue to flow until the end and you'll maintain a closed system. An added benefit is that when you get to the end you don't have to worry about a blow out either. It just stops gently.
 
It flowed all the way through the line to the keg, but just would stop at that point, and the flow would completely stop..thus popping out the airlock on my big mouth bubbler!
 
Bigz4ch, maybe a stupid question but did u pull the poppet or open the gas post on the keg?
Otherwise, it's probably up to a bad seal on the BMB

What others have discussed about feeding the gas out back into the fermentor(with the fermentor raised) works well and uses less co2.
You are only displacing 5g of liquid with canned co2 once, then your just swapping liquid for co2. You use less co2 in the process.
Closed loop vs closed transfer.
Also, if you have the kegs, just push the sanitizer to another keg. If you use distilled water, it lasts for a while. Trimming your gas dip tube flush and inverting the near empty keg helps flush out the last few oz.
 
I did pull the poppet, but perhaps i didn't twist it enough though so that is a possibility. So if I feed gas into the fermentor, is it enough to drain the liquid, and would I still want the fermentor elevated? I have also noticed that my flow when dispensing the beer from keg is very slow, and comes out foamy after settling for 4 days
 
This is KINDA what I did, just without the sanitizer push. I swished about a gallon of sanitizer in the keg so that it covered everything, then drained. At this point, I hooked up the CO2 and pressurized and purged the keg about 10 times. I hooked up a gas connector on the IN side and the fermenter to the OUT post. I just liked using the CO2 better than gravity. Picking the fermenter up to counter height sucks!

Just so you know, you cannot purge a keg that way and end up with 100% CO2 inside.

There's still quite a bit of of air (O2) mixed in with your CO2, even after 10 purges at 30 psi. You also use waaay more CO2 than the mere 6-7 gallons needed to push out the 5.25 gallons of Starsan (or water) which will get you a keg filled with 100% CO2.
 
Just so you know, you cannot purge a keg that way and end up with 100% CO2 inside. There's still quite a bit of of air (O2) mixed in with your CO2, even after 10 purges at 30 psi. You also use waaay more CO2 than the mere 6-7 gallons needed to push out the 5.25 gallons of Starsan (or water) which will get you a keg filled with 100% CO2.

Hmmm......I guess I never really considered the AMOUNT of CO2 being used....but that makes perfect sense. Once I've pressurized the empty keg to 25psi at 5 gallons......then purge multiple times.......holy crap! I realized that I wasn't purging ALL of the O2, but I never actually stopped to think about CO2 usage. Thanks.......I'll be changing my method.
 
Just so you know, you cannot purge a keg that way and end up with 100% CO2 inside. There's still quite a bit of of air (O2) mixed in with your CO2, even after 10 purges at 30 psi. You also use waaay more CO2 than the mere 6-7 gallons needed to push out the 5.25 gallons of Starsan (or water) which will get you a keg filled with 100% CO2.

Using a 5 pound CO2 tank, how many gallons of CO2 would those contain? Doing some math to see how many kegs we could push star san out of for 100% CO2 filling for O2 free transfers.
 
hmmm......i guess i never really considered the amount of co2 being used....but that makes perfect sense. Once i've pressurized the empty keg to 25psi at 5 gallons......then purge multiple times.......holy crap! I realized that i wasn't purging all of the o2, but i never actually stopped to think about co2 usage. Thanks.......i'll be changing my method.

me too!
 
Hmmm......I guess I never really considered the AMOUNT of CO2 being used....but that makes perfect sense. Once I've pressurized the empty keg to 25psi at 5 gallons......then purge multiple times.......holy crap! I realized that I wasn't purging ALL of the O2, but I never actually stopped to think about CO2 usage. Thanks.......I'll be changing my method.

Yeah, it's astonishing how much CO2 that takes, with extreme diminishing returns on each subsequent fill after 5x.

I started 100% liquid pre-purging kegs a couple years ago when I calculated that it takes way more CO2 to purge the headspace of a keg that's filled with "only" 4 gallons of beer! And that's when purged (5x at 30psi) to a still very substandard O2 level.

There are a few threads on 100% pre-purging. The key to the best methods is that you need to get rid of that little pocket of air that remains under the lid.
 
Annnnnnnddddd...........you're gonna tell us the trick to that.....right?:tank:


I've seen 2 good methods and 1 better-than-nothing method.

1. Cut the gas dip tube so it's flush inside. Fill the keg with water through the liquid port, venting out the gas port. Tilt to 45 degrees a couple times, then give it one final tilt just past 180 degrees to get the last tiny air pocket out of the lid. Then push all of the liquid out the of the liquid side using co2. I can elaborate more if interested. It's what i do.

2. Turn the keg upside down, and fill with water through the gas port. Vent through the liquid port. Once water is coming out of the liquid port (assuming the dip tube is standard) then the keg is as purged as you're going to get. Turn it over and push the liquid out the liquid port just like in #1.

3. I've seen another method that uses starsan bubbles to displace the air pocket in the lid, but i'm not totally convinced that the bubbles aren't made up of regular air and not co2.

You can do #2 with no modifications, and #1 by shortening the gas dip tube. Shortened gas dip tubes have other advantages too, like not back flowing when you're keg is full.
 
Using a 5 pound CO2 tank, how many gallons of CO2 would those contain? Doing some math to see how many kegs we could push star san out of for 100% CO2 filling for O2 free transfers.

From something I wrote a while ago, in a different thread. I hope it's accurate:

1# of liquid CO2 will produce 8.7 cu ft. of CO2 gas at 14.7 psi (=1 atm, regular atmospheric pressure). 1 cu ft. = 7.5 gallons. A corny keg has a volume of 5.5 gallons, give or take.

So 1# of liquid CO2 delivers 8.7 * 7.5 = 65 gallons of CO2 gas. Enough to dispense 65/5.5/(14.7+12)*14.7 = 6.5 kegs at 12 psi on your regulator.

Theoretically a 5# cylinder can thus dispense 5 * 6.5 = 32.5 corny kegs. That's without using gas for anything else like carbonating, purging kegs and headspaces, flushing fermentors, having leaks, etc.

[Edit] Here's a good link (http://www.airproducts.com/products...ht-and-volume-equivalents/carbon-dioxide.aspx) to convert an amount of liquid CO2 to gas and vv.
 
From something I wrote a while ago, in a different thread. I hope it's accurate:

1# of liquid CO2 will produce 8.7 cu ft. of CO2 gas at 14.7 psi (=1 atm, regular atmospheric pressure). 1 cu ft. = 7.5 gallons. A corny keg has a volume of 5.5 gallons, give or take.

So 1# of liquid CO2 delivers 8.7 * 7.5 = 65 gallons of CO2 gas. Enough to dispense 65/5.5/(14.7+12)*14.7 = 6.5 kegs at 12 psi on your regulator.

Theoretically a 5# cylinder can thus dispense 5 * 6.5 = 32.5 corny kegs. That's without using gas for anything else like carbonating, purging kegs and headspaces, flushing fermentors, having leaks, etc.

[Edit] Here's a good link (http://www.airproducts.com/products...ht-and-volume-equivalents/carbon-dioxide.aspx) to convert an amount of liquid CO2 to gas and vv.

Excellent info!!!! Thanks much!!
 
I've seen 2 good methods and 1 better-than-nothing method. [...]

Thank you for this great summary!

Everyone should copy this and stick in your beer notes!

Finding this pertinent information would be like a proverbial needle in the haystack, the knowledge buried in 100s of posts, half of which are inaccurate or incomplete, without knowing which they are.

Since I read them, I've been using a slightly different method, based on the original posts and threads @schematix so neatly summarized:


  1. Cut the gas post short.
  2. Fill the keg with Starsan (I guess water would be fine too) all the way to the rim, slide in the lid and lock it.
  3. With a disconnect and a piece of hose on the gas post, I then tilt the keg ~45° (gas post up) while pushing more Starsan (from another keg) into this one through the liquid post. I jiggle the keg while doing this and Starsan is pouring out into a bucket.
  4. I then push out a pint of Starsan (measured) and purge the headspace 5x at 30 psi before pushing it all out. This may be overkill, but I do it just in case an air bubble was still left behind.
  5. I let the keg sit for 20-30 minutes or so and blow out any Starsan that accumulated on the bottom. All but one of my liquid dip tubes go all the way to the bottom into the well.*
* If your liquid dip tubes are shortened, connect gas to the liquid post, invert the keg keeping the gas post pointing down. Let drip out like that under a 45-60° angle for 20-30 minutes. Keep tilted down while pressing the poppet or sticking a disconnect on it to blow out the remaining Starsan.
 
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OR you could put still fermenting beer in the keg, since active yeast is one of natures best antioxidants. You will also get the benefit of carbing your beer with pure co2, not oxidating it in the process of force carbing (negating most of the purging process anyway). Also when yeast are met with pressure they excrete glycerin which will help you with foam and head retention as well. :D
 
OR you could put still fermenting beer in the keg, since active yeast is one of natures best antioxidants. You will also get the benefit of carbing your beer with pure co2, not oxidating it in the process of force carbing (negating most of the purging process anyway). Also when yeast are met with pressure they excrete glycerin which will help you with foam and head retention as well. :D

do you purge your kegs at all when you do this?
 
That still leaves most of the lid bubble unless the gas dip tube is shortened.

Oh right, sorry I was not very descriptive with my explanation. Was doing too many things at once.

OR you could put still fermenting beer in the keg, since active yeast is one of natures best antioxidants. You will also get the benefit of carbing your beer with pure co2, not oxidating it in the process of force carbing (negating most of the purging process anyway). Also when yeast are met with pressure they excrete glycerin which will help you with foam and head retention as well. :D

I just started getting into low oxygen brewing so I could be wrong but I think people that try to eliminate oxygen from their brewing process do both. They get all oxygen out of the keg and transfer either while fermentation is almost done or add sugar and let it referment a little again.

I'd tend to agree though. The amount of air left in the lid gap is very small and that only contains something like 20% oxygen. And if you transfer with 3 to 5 points left or add sugar after fermentation, the yeast will scrub that small amount of oxygen.
 
The amount of air left in the lid gap is very small and that only contains something like 20% oxygen. And if you transfer with 3 to 5 points left or add sugar after fermentation, the yeast will scrub that small amount of oxygen.

I don't believe it is wise to consider the lid volume as 'very small'. If you're going through the efforts of water purging, you should do it right.

I also highly recommend natural carbonation. Not only does it save on bottle CO2, but it has all of the other benefits just mentioned...
 
..... or add sugar and let it referment a little again.

This is what I would love to do.....cut the gas tube flush, fill with StarSan and push it all out, add priming sugar, then transfer beer from the fermenter with CO2. So......any tricks on how to get that priming sugar in the keg before you transfer the beer from the carboy?
 
This is what I would love to do.....cut the gas tube flush, fill with StarSan and push it all out, add priming sugar, then transfer beer from the fermenter with CO2. So......any tricks on how to get that priming sugar in the keg before you transfer the beer from the carboy?

inject the priming solution into the carboy, wait an hour, rack to the keg.
 
This is what I would love to do.....cut the gas tube flush, fill with StarSan and push it all out, add priming sugar, then transfer beer from the fermenter with CO2. So......any tricks on how to get that priming sugar in the keg before you transfer the beer from the carboy?

The trick is to not put it in the keg lol Put it in the fermentor then transfer to the keg. Getting it into the fermentor without getting oxygen in it will depend on the vessel. Using a syringe works well. Sanitize it, draw in the solution and then tap the side to get all the air bubbles to the top and squeeze until solution comes out (just like they do when you get a flu shot).

You can get it into the keg if you want. Get a small soda bottle, add the priming sugar solution to the bottle and squeeze the bottle until the solution drips out the top. This removes the oxygen. Then cap with a carb cap. Fill that with CO2 to pressurize it. Connect a jumper from that to the beer out post of a purged keg and tip the bottle upside down.
 
You can get it into the keg if you want. Get a small soda bottle, add the priming sugar solution to the bottle and squeeze the bottle until the solution drips out the top. This removes the oxygen. Then cap with a carb cap. Fill that with CO2 to pressurize it. Connect a jumper from that to the beer out post of a purged keg and tip the bottle upside down.

HELL YES!!! That's genius! I have a carb cap, so this would be easy. When I cold crash, I put a very tight fitting balloon over my carboy to prevent suck back. I'm not sure how much oxygen exposure it gets when I take that off and put the orange cap on to transfer, but I can't imagine it is much and I try to keep air exposure to a minimum. Adding priming sugar to the fermenter after a cold crash just seems like a bad idea to me.
 
HELL YES!!! That's genius! I have a carb cap, so this would be easy. When I cold crash, I put a very tight fitting balloon over my carboy to prevent suck back. I'm not sure how much oxygen exposure it gets when I take that off and put the orange cap on to transfer, but I can't imagine it is much and I try to keep air exposure to a minimum. Adding priming sugar to the fermenter after a cold crash just seems like a bad idea to me.

If you pull the balloon back just a little, you won't get much oxygen in at all. Use a syringe and just stick the needle in the carboy around the balloon.
 
When you 'purge' a keg, how long do you pull up the lever? I have just been counting 1-2 seconds each time I purge, is this correct? And do I do it 5x at 30psi for best results?
 
When you 'purge' a keg, how long do you pull up the lever? I have just been counting 1-2 seconds each time I purge, is this correct? And do I do it 5x at 30psi for best results?

Read this whole thread. That doesn't really do anything. You need to fill the entire keg with a liquid.
 
I have lately been using co2 from the ferment or to purge kegs. Connect the blowoff tube to the liquid port and a spunding on the gas port. Someone here crunched the numbers and if you leave it connected for a full ferment you get a superior purge to any other method.
I like that its also free and way less hassle than a starsan purge. You just need an extra keg that you can leave connected to the fermentor.
 
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To even further reduce oxygen in the keg after pushing the starsan out you can pull ~15"Hg vacuum on the keg using a small vacuum pump. This pump has a 1/4"
male flare connection so it's easy to hook up to kegs. https://www.amazon.com/gp/product/B01N6IOBWF/?tag=skimlinks_replacement-20 This greatly speeds up transfer too.

I have a vacuum pump, and in my trials with keg vac, the way the corny is set up doesn't really work for vac, all my kegs lose seal under vacuum. Now, sankes, absolutely.
 
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