Keg Force Carbing Methods Illustrated

[Beenym88]

What's the best closed beer transfer method from a plastic fermenter to a keg? Is there a video format version to demonstrate it (non-native eng speaker here)?

This was something that I was going to do for my next batch, but a fellow homebrewtalk member said it wasn't enough.

It’s very dependent on your fermenter can it hold pressure?

 

[chazam]

It’s very dependent on your fermenter can it hold pressure?

It's a basic plastic fermentator bucket. Similar to the one in the video, but without a tap (tap I need to drill and install myself). It can hold a little bit pressure but not much.

 

[tracer bullet]

What's the best closed beer transfer method from a plastic fermenter to a keg?

I run the spigot coming out of the fermenter into the keg, and a return from the keg going back to the top of the fermenter.

* The beer coming out of the fermenter comes out of the bottom - my fermenter has a spigot
* It goes into the keg through what is normally the "out" side, connecting to the metal pipe inside (less splashing just in case)
* The return line comes from the keg on the "gas in" side, because the tube there is so short
* The return line goes into the top of the fermenter through whatever available location you have (perhaps where you had an airlock).
* The fermenter is higher than the keg

Gravity draws beer from the fermenter into the keg, and the return line simply allows the air to move out of the keg and go into the fermenter to replace the beer coming out.

Definitely fill the keg w/ water or a star-san or similar solution and use CO2 to purge it out, so you know your keg starts with only CO2 inside.

 

[Srdjan Ostric]

I have never been successful with force carbing any beer. I usually just turn the psi to between 10 and 15 and wait a week. I have found that lower pressures just don't work. I mean they probably work slowly, but who wants to wait 3 weeks?

 

[Bobby_M]

I have never been successful with force carbing any beer. I usually just turn the psi to between 10 and 15 and wait a week. I have found that lower pressures just don't work. I mean they probably work slowly, but who wants to wait 3 weeks?

Pressure is dictated only by the beer temperature and your desired carbonation level. I don't think I'd say that any particular pressure doesn't work, it's just not the right one for the volumes of CO2 you're looking for. There's a very big difference between 10 and 15 psi.

If 15 psi gets you were you want to go in one week, it will be overcarbed in another week if you don't turn the pressure down. If it takes 3 weeks to get you where you want to go, you'd just leave that pressure alone for the rest of the keg's life.

 

[Srdjan Ostric]

I appreciate it. I taste it every 2 to 3 days

 

[Srdjan Ostric]

Pressure is dictated only by the beer temperature and your desired carbonation level. I don't think I'd say that any particular pressure doesn't work, it's just not the right one for the volumes of CO2 you're looking for. There's a very big difference between 10 and 15 psi.

If 15 psi gets you were you want to go in one week, it will be overcarbed in another week if you don't turn the pressure down. If it takes 3 weeks to get you where you want to go, you'd just leave that pressure alone for the rest of the keg's life.

Also, in your original post, which was excellent by the way, you had a graph with a line, and it didn't show up. At least not on my phone. I think that might be helpful if I could see that.

 

[day_trippr]

That graphic has vanished so many times I've kept a copy just to refresh the thread when needed

Cheers!

 

[bracconiere]

doing it by weight myself, being 1.2ozs seems right.....4 of these and be done with it?

https://www.supplyhouse.com/Westwoo...snk-AqdNXwJxUcRyEqD2yeJ80PGWgD1AaAkYZEALw_wcB
(with one of those little regs for them.....)

edit: or two of these at $1 a piece?

https://impeccable-o.com/products/i...9rXmDnVWT54PJWqq4b7PjU_3E2VTLjj0aAjNhEALw_wcB

 

[mtemple]

Weird question. But if I kegged a batch of beer and kept it lagering in my fridge for about a month, would I be able to then force carbonate it after that? Seems weird to carbonate after having it sit for that long "flat".

 

[bracconiere]

Weird question. But if I kegged a batch of beer and kept it lagering in my fridge for about a month, would I be able to then force carbonate it after that? Seems weird to carbonate after having it sit for that long "flat".

yes? co2 dissolves in water under pressure, then comes out of solution when depressurized....

edit: but if it was already under pressure, it'd probably be carbed allready, and not to burst it or anything....

 

[balrog]

If'n you put it in the keg at room temp, closed it up, and stuck it in the fridge, it'll be under negative pressure initially as the headspace gas contracts due to temperature, which then, over a couple days, will draw CO2 dissolved from fermentation out of the beer. Likely it will be quite flat. And you can apply CO2 under pressure to increase the dissolved CO2 in solution at any time without ill effect.

 

[bracconiere]

If'n you put it in the keg at room temp, closed it up, and stuck it in the fridge, it'll be under negative pressure initially as the headspace gas contracts due to temperature, which then, over a couple days, will draw CO2 dissolved from fermentation out of the beer. Likely it will be quite flat. And you can apply CO2 under pressure to increase the dissolved CO2 in solution at any time without ill effect.

thinking about that, i'd be worried the lid seal would fail.....

 

[balrog]

thinking about that, i'd be worried the lid seal would fail.....

I didn't go into that and the O2 ingress, blah blah blah, but I'd always pop a few PSI on a keg, if not a whole lot of PSI, before I stuck it in the cooler.

 

[day_trippr]

Calling @doug293cz !

I would be surprised if a keg ever "went negative" given at the end of fermentation beers typically have somewhere around .6 to .8 volumes of CO2 already extant...

...although if that was always true I wouldn't have to provide low pressure CO2 to keep my fermenters from collapsing during a cold crash...

NVM

Cheers!

 

[balrog]

Put any vacuum on a beer with any dissolved CO2 and it comes right out pretty fast.

Not that I've done that. Vacuum guys getting pretty particular with their oil diffusion "babies" if you even joke about that sort of thing...

 

[doug293cz]

Calling @doug293cz !

I would be surprised if a keg ever "went negative" given at the end of fermentation beers typically have somewhere around .6 to .8 volumes of CO2 already extant...

...although if that was always true I wouldn't have to provide low pressure CO2 to keep my fermenters from collapsing during a cold crash...

NVM

Cheers!

At 65°F and 14.7 psi CO2 partial pressure (0 psi gauge if headspace is 100% CO2) the equilibrium carbonation level is 0.88 volumes. So, that is how much carbonation should be in your beer at the end of a 65°F fermentation.

At 33°F and 14.7 psi CO2 partial pressure, the equilibrium carbonation level would be 1.56 volumes.

So, if you sealed the keg, and cold crashed, some of CO2 in the headspace would dissolve into the beer, lowering the pressure in the headspace. This would reduce the headspace pressure below 14.7 psi absolute (0 psi gauge), so the gauge pressure would go negative.

It's possible to calculate where the pressure would end up when equilibrium is reached, if you are interested.

Brew on

 

[doug293cz]

At 65°F and 14.7 psi CO2 partial pressure (0 psi gauge if headspace is 100% CO2) the equilibrium carbonation level is 0.88 volumes. So, that is how much carbonation should be in your beer at the end of a 65°F fermentation.

At 33°F and 14.7 psi CO2 partial pressure, the equilibrium carbonation level would be 1.56 volumes.

So, if you sealed the keg, and cold crashed, some of CO2 in the headspace would dissolve into the beer, lowering the pressure in the headspace. This would reduce the headspace pressure below 14.7 psi absolute (0 psi gauge), so the gauge pressure would go negative.

It's possible to calculate where the pressure would end up when equilibrium is reached, if you are interested.

Brew on

Ok, found my spreadsheet that does this calculation. When equilibrium is reached after cold crashing 5 gal of beer with 0.35 gal of headspace from 65°F to 33°F, the headspace absolute pressure (CO2 partial pressure) would be 8.55 psia, and the gauge pressure would be - 6.15 psig.

Brew on

 

[balrog]

This is why we keep him around.