Force carbonation of 1 gallon keg

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Alf34

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Hi brewers

I just kegged my Homebrew for the first time, it's a 1 gallon keg that sits in my fridge, sideways ( space issue) at 48 degrees. After reading about burst carbonation techniques, I decided to set to pressure to 40 psi for 24 hours, then turn it down to 14 psi for serving pressure and leave it for another day.

I do realize now it was a big mistake since we are taking about a 1 gallon keg, not a full size 5 gallon keg, so not that much pressure and time are needed. First few pours were ok. Then almost all foam, and very very slow, to the point of no beer flow. Also, I can see a lot of co2 bubles in the beer line, so its seems that it's definetly a matter of ovecarbonation and inadequate pressure.

The beer line is 1 meter long and 5mm internal diameter by the way.

Next time I plan to use the set and forget method and play it safe. I know that it usually takes around 7-10 days to carbonate using that method for a 5 gallon keg. Any idea how long it would take for a 1 gallon keg? If it is only, as I am assuming, a matter of 3-4 days, I really dont mind waiting, specially after seeing the potencial risks of burst carbonating.

Also, if burst carbonating such a small batch, any idea what pressure and how long it it would take to carbonate?

Thanks for your answers!
 
What knd of tap do you have attached? ...1m of 5mm ID line is too short in most circumstances. If the 1meter length is the important part to you, you'd need the 3mm ID line. I can't answer for picnic taps, but with that line and length you'd need a flow control faucet or disconnect.
:mug:
 
First thing that comes to mind (other than the over carbonation) is hop debris in your liquid keg post. That used to happen to me before I had a good dry hop and transfer regimen. You could de pressurize and remove the leg post to see if debris inside the spring.

Next thing that comes to mind is the fact you have the keg sideways. I think you'd have trouble pushing beer out if the gas post is below the liquid level. Maybe not. The other thing is your liquid pickup tube. Maybe sideways it's above/at the liquid line so you spit foam. If you have a floating dip tube, depending on the type, it might not have the tube sitting under the liquid line.
 
@micraftbeer has a good point on the pickup when keg is sideways.
The liquid out dip tube can be down the side, or angled to the center, both at the bottom of the keg. You need to know the geometry in order to know why having the keg sideways is a problem.
1734539199761.png
 
having the gas in tube in or out of the beer is not a problem for pushing the beer out.

it *can* be a problem if you inadvertently reduce the CO2 gas cylinder or regulator pressure to a pressure that is less than what pressure is in the keg. If the gas in tube is below liquid level and keg pressure is higher, it ***WILL*** force beer up the gas in line, into the regulator, causing a mess, massive headaches, projectile diarrhea, cats and dogs living together, real wrath of God type stuff. Avoid that. You have been warned.
 
Problem solved, I think. A few days ago I had a gas leak coming from the gas disconnect that was not properly screwed.

So I had do disassemble this check valve disconnect and assemble everything back. Well I did not assemble all parts in the right order, so esentially it was not working as supposed to and gas was not not flowing to the beer. I just realized when cleaning and trying to push pbw solution out of the keg, 0 flow. I tried with a normal untouched gas disconnect, no problem pushing it out.

For next time, any idea what pressure and time to carbonate this 1 gallon keg? Either set and forget or burst carbonate such a small batch.
 
Problem solved, I think. A few days ago I had a gas leak coming from the gas disconnect that was not properly screwed.

So I had do disassemble this check valve disconnect and assemble everything back. Well I did not assemble all parts in the right order, so esentially it was not working as supposed to and gas was not not flowing to the beer. I just realized when cleaning and trying to push pbw solution out of the keg, 0 flow. I tried with a normal untouched gas disconnect, no problem pushing it out.

For next time, any idea what pressure and time to carbonate this 1 gallon keg? Either set and forget or burst carbonate such a small batch.
I am no expert.
I always get better results set and forget.
It always takes more than one week and less than a month. Given that it's chemical reaction to dissolve CO2 into liquid, I would think 1/5th the volume would take 1/5th the time.

I used to have a spreadsheet from somewhere that gave me time to get volumes dissolved given burst pressure, beer volume, headspace volume. I'll try to look it up when I get home. It was not elegant, you have to try diff values until it comes out as I never converted it to the Excel solution stuff, but it always seemed to be a bit under what I wanted. I had better (anecdotal) luck just hooking up 30psi for "about two days" and then unhook everything and let it sit, basement temp.

Anyway, I'll see if I can find it.
 
You might find this chart handy, I've used it many times with success on different size batches. Granted, you need to be patient and wait for 10-14 days. Using this method, you're less likely to overcarb tho, so that is the benefit.

https://www.brewersfriend.com/force-carbonation-chart/

When I'm feeling especially impatient, I'll set a 30 PSI, 30 Degrees F and 3 days "usually" does the trick. (like right now, I'm on day 3 in a couple hours with a new batch and wondering if it will be over/under or just right..always seems like a gamble) More hits than misses though.
 
THis is what it looks like. I cannot recall where I found it to give proper bibliographic citation, let me know if you want a copy.
1734561000716.png


I also have this one that speaks more to TIME to carb. It is really just someone's data for 5 gallons held at 36F.
1734561040505.png
 
I believe that the limiting issue leading to long carbonation times is diffusion of the dissolved CO2 through the rest of the keg. That's to say, the thin layer at the very top comes into equilibrium relatively quickly, but that means no more CO2 is dissolved until the stuff at the top makes its way deeper into the keg. (Diffusion is slow enough, in fact, that I'd expect mixing driven by convection or vibration would be what matters. This suggests to me that a small shaker motor attached to the keg would allow for faster set-and-forget carbonation times.)

So you'd expect a 1-gallon keg -- which is usually about the same diameter as a 5-gallon keg -- to carbonate much faster. That has been my experience, with set-and-forget only taking a couple of days.

This also suggests that if you have the option of using a shorter, squatter keg, it will carbonate faster -- the surface area goes up and the diffusion length goes down.

When I'm feeling impatient, I do set-and-shake. Once the beer is cold, this can be very fast, too, and you won't overcarbonate.

If you're going to store a keg on its side, I'd recommend a floating dip tube, specifically this one. It pretty much eliminates out-tube clogging, as well.
 
small kegs carb up very quick i just carbed a 1.6 gallon in 3 days. i did 24 hours at 25 then 2 days at 12 and then it was good
 
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