Closed system transfer from carboy to keg: What you need

[lilbova3]

I'm looking into kegging now! I'm going to get a kegerator with two taps, order some ball lock corny kegs but I'm having trouble figuring out what all I need for a closed CO2 transfer from my carboy to my keg. I'm ordering a kegerator, not putting one together so it's going to come with all the lines, CO2 tank, tap tower and handles etc. I just need to make sure that the lines are fit for ball lock cornys, correct?

Once I know my kegerator will fit ball lock cornys my question is what all do I need to purchase and hook up/set up for a closed transfer? I'm not very witty when it comes to this kinda stuff and building putting it together. I've been looking and researching topics about this but don't really understand what a "beer MFL ball lock disconnect - barbed" but know that I will need one for the transfer into my keg through the dip tube. Actually, I just don't know what MFL means. I've read metabrewing.com's post about this (http://www.metabrewing.com/2014/08/avoiding-oxygen-when-kegging-co2.html) but am not sure where to go out and buy everything and don't know where to buy everything (I'm guessing Home Depot or Lowe's should have most of it and some stuff will have to be from a homebrew website as I don't have a LHBS nearby).

Here's a list of things I think I need and stuff I'm probably missing. Please help fill in what's needed.

-Carboy cap
-SS racking cane (5/16" ID tube needed)
-Extra CO2 tank (so I don't have to disconnect the one from my kegerator, will use it to purge kegs and apply pressure for transfer)
-CO2 tank regulator
-Ball lock LIQUID disconnect - barbed (I can attach tubing straight to that correct, don't need any fittings?)
-Ball lock GAS disconnect (needed for purging the keg and will keep the line hooked up when I fill keg)
-Clamps

Now where I'm stumped is trying to get the proper tubing size and connects from my CO2 tank and regulator to my carboy cap, which will need a proper connect as well because I'm sure the tube won't fit right onto the carboy cap. Then the proper tubing from my racking cane (which I know I need to use 5/16" ID tube) to my ball lock LIQUID disconnect. I imagine 5/16 will be too big for the disconnect. Will tightened clamps be enough?

Sorry for the long post, any help would be appreciated!

 

[day_trippr]

I'm presuming your racking cane OD is what's driving the tubing ID.
If you went with an MFL liquid disconnect, you can get a 5/16" barb on a 1/4" FFL swivel nut here and other places.

The other piece is the CO2 to carboy cap business.
I wanted to be able to simply snap on a ball lock gas QD, so I used a Firestone ball lock gas post with a matching Firestone-to-1/4"-FFL post adapter, then a 1/4" MFL-to-1/4" barb, which gets clamped into the smaller carboy cap port.





For the rare carboy-to-carboy racking I have a second dip tube and a length of nekkid tubing.
About all that one gets used for is my stouts...


Cheers!

 

[mongoose33]

Let me add to DayTrpper's excellent post:

I have an extra keg filled with Star-San; it becomes the next keg I'm going to fill with beer. I use a jumper line to connect the keg filled with Star-San to an empty one (it connects the OUT posts). I pop the lid of the empty keg to allow pressure to release, apply CO2 pressure to the full Star-San keg, and push the Star-San into the empty keg.

This ensures not only is the first keg sanitized (which it is--I cleaned it first, then filled w/ Star-San), but I'm replacing the fluid with CO2. This becomes the keg into which I'll transfer the beer, and it has almost no oxygen in it.

I'll pop the lid of the now-empty keg just enough to let it drain, invert over a sink so any remaining dregs of Star-San can dribble out, and then reset the lid for now. Then I'll drain the beer from the fermentor into that keg, which is now almost completely filled with CO2. Virtually no risk of oxygen contamination.

Meanwhile, the Star-San from the first keg is now in the second one, which then awaits another batch of beer.

You could, if you have no extra keg, simply push that Star-San into a 5-gallon bucket to save for the next iteration.

 

[Tommydee]

Day tripper, know this is old, but while this is a good setup, it ia bit unsafe. Generally bad idea to pressurize glass this way, a no no in the industrial setting for sure. If you're going to continue with this setup, at least remove the worm drive on the hood, so that the cap will pop off. A carboy has a lot of surface area, and if you have a crack/weak point in the glass, force = pressure times area, and you can get some large pieces of glass coming at you with serious force.

I was surprised to find LHBS actually sells a rig set up to put a CO2 tank on a carboy similar to this . Risky business if you ask me.

 

[govner1]

Take a look at the setup offered by Love2Brew. I got one as a BD present earlier this month and will use it next week.
You could easily assemble the pieces separately.

 

[Izzie1701]

Is this really necessary. I have kegged over 25 batches, including a mead, and never had any oxidation issues. I typically purge the keg, use auto siphon racking cane with tubing right to the bottom of the keg and fill away. After filling I put the cap on the keg, fill to 10 psi and purge 3 times. Then force carb. I get doing this from a bright tank and using counter pressure but the safety of pressurizing glass to odds of a beer oxidizing seem a little lopsided.

 

[govner1]

Is this really necessary. I have kegged over 25 batches, including a mead, and never had any oxidation issues. I typically purge the keg, use auto siphon racking cane with tubing right to the bottom of the keg and fill away. After filling I put the cap on the keg, fill to 10 psi and purge 3 times. Then force carb. I get doing this from a bright tank and using counter pressure but the safety of pressurizing glass to odds of a beer oxidizing seem a little lopsided.

There shouldn't be an issue w/"pressurizing" your carboy since you only use 2-3 psi for the transfer. Unless you have a cracked/damaged carboy which is going to break at some point.
I happen to use all BB's so breakage isn't really a concern.just keep an eye on your regulator setting.

 

[zgja2]

Is this really necessary. I have kegged over 25 batches, including a mead, and never had any oxidation issues. I typically purge the keg, use auto siphon racking cane with tubing right to the bottom of the keg and fill away. After filling I put the cap on the keg, fill to 10 psi and purge 3 times. Then force carb. I get doing this from a bright tank and using counter pressure but the safety of pressurizing glass to odds of a beer oxidizing seem a little lopsided.

It depends. For most beer, a purged keg and standard racking is fine. If you want to brew some highly hopped, multi dry hop, NE IPAs and the like this and other steps to reduce O2 exposure are absolutely necessary. If you dont you will have crap beer in a week or two.

 

[Izzie1701]

It depends. For most beer, a purged keg and standard racking is fine. If you want to brew some highly hopped, multi dry hop, NE IPAs and the like this and other steps to reduce O2 exposure are absolutely necessary. If you dont you will have crap beer in a week or two.

Shouldn't it be the opposite as alpha acids oxidize after ethical and acetic acids. Alpha acids are the second to last acid to oxidize. A high alcohol beer will
Oxidize quicker then a high hopped beer. Either way I have done dry hopped IPAs and never pressurized a glass carboy. Also 2-3psi is still enough to cause some serious harm when a carboy explodes. F=MA and a face full of shattered glass. 3 psi would have the equivalent damage of around a piece of glass being blown at you with a 100mph wind. A 5psi explosion will rupture ear drums. So it's still a pretty Big Bang. Just because it's a small number doesn't mean it's harmless. Your still putting 3 lbs of pressure on every square inch of your glass carboy.

 

[govner1]

Or you could use BB's!
Don't forget the pressure is pushing your beer from the carboy into the keg (or another carboy) so you're not applying a constant pressure to the glass. Obviously, you need to vent the receiving vessel as the transfer progresses.

 

[zgja2]

Shouldn't it be the opposite as alpha acids oxidize after ethical and acetic acids. Alpha acids are the second to last acid to oxidize. A high alcohol beer will
Oxidize quicker then a high hopped beer. Either way I have done dry hopped IPAs and never pressurized a glass carboy. Also 2-3psi is still enough to cause some serious harm when a carboy explodes. F=MA and a face full of shattered glass. 3 psi would have the equivalent damage of around a piece of glass being blown at you with a 100mph wind. A 5psi explosion will rupture ear drums. So it's still a pretty Big Bang. Just because it's a small number doesn't mean it's harmless. Your still putting 3 lbs of pressure on every square inch of your glass carboy.

two things...

1. I am not 100% on the science behind it but there is plenty of data and my experience to back it up. Highly hopped beers are VERY susceptible to o2. Trust me, drain pouring 5 gallons of beer with 16 oz of hops in it is rough.

2. I should have clarified. I would NEVER add any pressure to any glass vessel. Especially a carboy. I do not condone using them at all. I ferment in 1/4 bbl sanke kegs and closed xfer right into the serving keg. I recommend this method among others to reduce O2 (like continuous purging of head space while adding dry hops or taking samples)

Just my method. YMMV. but it works.

 

[dcs]

Hello!

TommyDee is correct.

No one should ever intentionally pressurize a glass fermentation carboy to any level of pressure. They're not designed or constructed or rated for it.

Izzie is also correct.

Aerated beer leading to oxidation or other evils associated with the very presence of oxygen in the universe has ruined almost every batch of beer ever made throughout human history.

Oh wait. No. Sorry. Almost no batch of beer ever made has been ruined by oxygen. Because you really kind of have to aerate the bejeezus out of your beer during transfer if you want to have even a chance of ruining the beer with oxygen.

Just sayin is all.

There are some beers out there that you need to age for a year or so before drinking. If you make one of those beers, you probably want to be extra careful, but for everything else, just be normal careful. Try to avoid making bubbles when you transfer.

I read a post today that debated how much oxygen enters back into a purged corny keg (against the flow of outbound CO2) while you are venting out most of the CO2 that you just used to push out a full keg of water or sanitizer solution.

For realz.

 

[brew703]

I'm presuming your racking cane OD is what's driving the tubing ID.
If you went with an MFL liquid disconnect, you can get a 5/16" barb on a 1/4" FFL swivel nut here and other places.

The other piece is the CO2 to carboy cap business.
I wanted to be able to simply snap on a ball lock gas QD, so I used a Firestone ball lock gas post with a matching Firestone-to-1/4"-FFL post adapter, then a 1/4" MFL-to-1/4" barb, which gets clamped into the smaller carboy cap port.

View attachment 360078
View attachment 360076
View attachment 360077

For the rare carboy-to-carboy racking I have a second dip tube and a length of nekkid tubing.
About all that one gets used for is my stouts...
View attachment 360079

Cheers!

Trying to get my racking equipment. I found these at AIH. these appear to be the same as what you have, right?

https://www.homebrewing.org/SS-14-MFL-x-14-barb_p_3607.html
https://www.homebrewing.org/Plug-Adapter-14-FFL-x-1932_p_4637.html

 

[day_trippr]

The 1/4" MFL-1/4" barb is definitely the same.
The post adapter I used is 1/4"FFL x 9/16-18" to match up with Firestone posts.
The one you linked is 1/4" FFL x 19/32" (-18, probably) which matches Cornelius posts.
You definitely need to make sure you buy mating posts and adapters...

Cheers!

 

[brew703]

Would this work? https://www.homebrewing.org/Used-Firestone-Gas-Post-916-18_p_2616.html

 

[day_trippr]

Again, it's all about the threads.
That's a Firestone compatible (9/16"-18) threaded post.
The 19/32"-18 adapter you linked is not compatible with Firestone fittings.

So, either find a Firestone compatible adapter like the one I originally linked, or find a Cornelius post to use with the Cornelius adapter you linked...

Cheers!

 

[brew703]

would this work?
Post https://www.homebrewing.org/AIH-New-Keg-Gas-Post_p_7459.html
Adaptor https://www.homebrewing.org/Plug-Adapter-14-FFL-x-1932_p_4637.html
Barb https://www.homebrewing.org/SS-14-MFL-x-14-barb_p_3607.html

If these work, the adaptor screws into the post then the MFL barb screws into the adaptor?
Just trying to get everything from one place as I will be ordering kegs from AIH.

 

[brew703]

Got it figured out and parts ordered.

 

[radwizard]

I have a pretty noob question about this:
How do you know if the keg is full (for example you carboy is bigger then 5, or you have an ss tank), do you weigh it? Do you just fill it until beer comes out of the pressure release valve, and then pour a little back out?
I'm getting ready to do some co2 transfers outta my ss brew bucket, and just wanted to cover my bases....

 

[day_trippr]

fwiw, I have the keg on a digital shipping scale while I'm filling it.
I use 4.90 * 8.345 * FG to calculate the target weight for a fill right to the top of the keg sidewall (typically ~41.5 pounds) so as not to affect the carb rate.

btw, if you happen to use a digital scale that isn't smart enough to realize something's happening and shuts itself off, don't target net weight, use the gross weight (beer plus keg) so you just re-zero and put the keg back on the scale if it takes a nap...

Cheers!

 

[radwizard]

fwiw, I have the keg on a digital shipping scale while I'm filling it.
I use 4.90 * 8.345 * FG to calculate the target weight for a fill right to the top of the keg sidewall (typically ~41.5 pounds) so as not to affect the carb rate.

btw, if you happen to use a digital scale that isn't smart enough to realize something's happening and shuts itself off, don't target net weight, use the gross weight (beer plus keg) so you just re-zero and put the keg back on the scale if it took a nap...

Cheers!

That is what I was thinking. I have digital scale that should work. What kind of situation would I be looking at if I messed it up (got distracted, or miscalculated). With 1 psi pushing out the beer, it seems like there wouldn't be to bad of a mess. I wanna prepare the area for a worse case situation. Murphy's Law seems to rule my life....

 

[mongoose33]

I have a pretty noob question about this:
How do you know if the keg is full (for example you carboy is bigger then 5, or you have an ss tank), do you weigh it? Do you just fill it until beer comes out of the pressure release valve, and then pour a little back out?
I'm getting ready to do some co2 transfers outta my ss brew bucket, and just wanted to cover my bases....

I use a low-tech method....I always crash the beer down to 32-36 degrees prior to kegging. When the beer transfers to the empty keg, I get a condensation line that climbs the side of the keg as it fills. When it gets to the top, I stop filling.

 

[Hayden80]

I'm glad I stumbled upon this thread. I am going to be kegging my first brew in a few weeks and I was going to pressurize a glass fermenter. That is out of the question now. Guess I'll have to figure something else out now.

 

[ten80]

I pressure transfer out of glass carboys (3, 5, and 6.5 gal) all the time and it's safe if you take precautions. I set my regulator to about 3 PSI and use and orange carboy cap with a racking cane and gas flare fitting added. The carboy cap pops off the carboy, acting like a pressure release valve if I exceed about 4 PSI. There's also fair bit of CO2 that blows by the racking cane to carboy cap "seal."

 

[day_trippr]

I also do CO2-push transfers out of my 6.5g italian carboys, but I never go higher than 2 psi, and that's just to get the flow going.
After that I dial down to ~ .5psi, let gravity do most of the work with the low head pressure back-filling the increasing head space.

One could add an extra margin of safety using a "pneumatic fuse", as I do during cold-crashing...

Given the two-ported carboy cap a tee or wye would be required, but it could be done.
I can testify that the balloons actually work as intended in this application.
Before I found a fixed output .5 psi secondary regulator, a couple of the early batches 'sploded the balloons due to primary regulator creep (it's not easy to set most regulators that low)...

Cheers!

 

[gpops]

I'm presuming your racking cane OD is what's driving the tubing ID.
If you went with an MFL liquid disconnect, you can get a 5/16" barb on a 1/4" FFL swivel nut here and other places.

The other piece is the CO2 to carboy cap business.
I wanted to be able to simply snap on a ball lock gas QD, so I used a Firestone ball lock gas post with a matching Firestone-to-1/4"-FFL post adapter, then a 1/4" MFL-to-1/4" barb, which gets clamped into the smaller carboy cap port.

View attachment 360078
View attachment 360076
View attachment 360077

For the rare carboy-to-carboy racking I have a second dip tube and a length of nekkid tubing.
About all that one gets used for is my stouts...
View attachment 360079

Cheers!

Been reading through all your posts on this topic and trying to replicate the setup. Your pictures are a real help! My question is what size stainless racking cane fits in the carboy hood (3/8" or 1/2")?

 

[day_trippr]

Lemme check...micrometer says 3/8" OD.
You do have to work it through the bore of a virgin carboy cap, helps to use some lube. 1/2" would likely rupture the cap.
I have my racking rigs set up all the time so it was a one time deal...

Cheers! (sorry, got a big risqué there )

 

[SanPancho]

just an FYI here on this old thread- i searched for this because i couldnt remember where i got the parts for the setup. i was intending to buy another of the post-to- post adapter- to+ mfl/ffl- mpt/fpt-1/4-barb-to- whatever and i dropped something on my foot that hurt like hell.

a carbonation cap. the stainless kind, with the little barb attachment underneath that is supposed to be for adding carb stones or something crazy like that.

a bit heavier than the post/thread adapter/barb set up, but you can get them on ebay or alibaba for like $5-10 delivered. even amazon has them $10 with prime delivery. AIH, chi, norcal,etc, seem to all run at least $10 -15 for the three separate parts, plus shipping.

if weight is not a concern, stainless carbonation cap with the barb on the bottom is cheap one-item solution.