BigB
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OR you could just look at the first post and get the link there.
Keg Force Carbing Methods Illustrated
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OR you could just look at the first post and get the link there.
wattershed
Member
Someone please jump in if I'm incorrect about this, but he says he's got 5g in a 15g keg. At 11psi wouldn't the last week he's been carbing it have mostly been spent on filling the headspace?
Either bump it up a bit (18ish) for another week, then test every other day until it seems good and back it down to 11, or just wait another 3 weeks or so until the 11psi has both filled the headspace and infiltrated the beer. Just don't crank it and leave it cranked. You can always add more, but it's annoying and takes a long time to calm a beer down, CO2-wise.
solavirtus
Well-Known Member
The head space fills up to the set pressure very quickly. Most of the time is spent on the CO2 from the head space dissolving into the beer. Since the regulator keeps the head pressure constant, it shouldn't take any longer in a 15 gal keg than a 5 gallon. It could even take less with a larger gas-liquid interface.
I think ill try this method
CheemsAF
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Man, we could have saved a lot of chaos by going from post 1 directly to this one.
If you do run the numbers, don't forget to consider the surface area between the headspace and beer. I think it matters but I'm not sure. I always wanted to actually measure the partial pressure every 24 hours for 3 weeks to better plot the real rates of absorption but I don't have the discipline to pull it off.
Bobby M,
After taking a hiatus to the wonderful country of Afghanistan for 9+ months, I started to experiment with the a few different partial pressure laws on my beers upon my return. Namely Henry, Amagat, and Daltons' laws. There are way too many variables to come up with for a single solution (time, beer temp, beer density, CO2 temp, beer volume, surface area, and tap height or press release height). The one variable that doesn't compensate is the line pressure, which was throwing me for a loop. Essentially I was over-carbing all of my beers using a boost carb method that I came up with; or so it seemed. It turned out my lines (3.5 feet long), where way too short. The partial pressure in the keg was probably close, but the lines were ruining it. I.e. the beer was probably the correct vol CO2, but once it left the keg, the CO2 quickly came out of solution. I swapped my lines out for 9 foot lines, and it made all the difference. One thing I'm still trying to determine in balancing your keg, is where is the reference height that you calc your tap height off of is...the bottom of the pickup tube, the top of the keg, or where the top of the beer in the keg (that is always dropping). I would argue it's the moving beer height within the keg. But this thread is getting way too long. Happy New Year's...
If you rely on a bottle of CO2 gas for carbing your kegged beer, there are basically two ways to go about it; set and forget and what I'll call "burst carbing". Some folks talk about this second method as "force carbing" but it's all done with force so forget it. For example sake, let's assume you want to carb your 45ºF beer to 2 volumes of CO2....
Set and forget relies on certain gas laws that will determine the carbonation level based on pressure and temperature. The volumes of carbonation will eventually reach an equilibrium to the head space pressure that is applied (what the regulator is set to). You'd use the charts like this one http://www.kegerators.com/carbonation-table.php to figure out what that pressure needs to be. In our example, the chart shows it would take 9 psi to reach 2 volumes in your 45ºF beer.
The second method, burst carbonation, uses a much higher initial pressure and even some gas diffusion techniques like shaking or airstones to encourage a quicker solution of the gas. In our example, you might put 30psi on initially. If you refer back to the chart, you'll see this pressure, if left long enough will equilibrate to 3.79 volumes given enough time. The trick/difficulty in this method is knowing how long to leave it at the elevated pressure to get close to your desired volumes without overcarbing.
Some people understand pictures better than words so I drew this.
The green line is the set and forget method. You can see that it will take about 2 weeks to reach your desired volumes. Some folks will argue that they have carbonation in 1 week but "some" carbonation is not exactly equilibrated carb level though you might enjoy it anyway. I'm not 100% sure how long it takes but I have noted an increased carb level between week 1 and 2 on more than a few batches so I'm calling it 2 weeks to get it pretty close. You'll notice a small increase from week 2 to 3 but it's slight.
The blue line is just an example of a well executed boost carb. You'd leave it at approximately 3 times the equilibrium pressure for 24 hours, then drop it down and purge the keg so the headspace is now at the "chart pressure". If you do it right, you'll get close and then it will only take a couple more days to reach your desired volumes.
Highlighted for emphasis: More often than not, people in a hurry will try boosting even more by going with higher pressures and/or shaking the heck out of the keg. This usually results in what the red line is showing. You overshoot the carb level and then fight with the keg for several days to get it back down by purging the pressure a few times.
The final point I want to make is that the only reason I'd advocate a boost carb is when your beer has already aged/conditioned prior to making it to your kegerator and you need the beer to be drinkable in less than two weeks (poor planning on your part of course). I noted on the chart that if you went from primary right to keg at week zero, no matter how fast you carb, it will still take at least 3 weeks to taste decent. Therefore, why boost carb at all?
I'm new to kegging-
does the 'set it and forget it' method still apply if, for example, I want to only carbonate 1 gallon in a 5 gallon keg? It would still take 2 weeks to carbonate if set to 10 psi?
Is there any way to figure out how much quicker or is it simply by trial and error? Like say it takes 2 weeks for 5 gallons, should it take 1/5th the time (3 days) for 1/5th the volume (1 gallon) (assuming same surface area exposed to the CO2)?
I would like carbonate some of my mead, but not all of it. Probably no more than 2 gallons at a time. Is the best way to go about this buying a 2.5 gallon kegging system like this:
http://www.homebrewing.org/25-Gallon-Metal-Handle-kegging-system_p_2972.html
peterlonz
Well-Known Member
Re: Bobby M's post 646.
An excellent & simple answer to the often asked question of newcomers to carbing.
Addressing particularly newcomers, I think several additional points are worth making:
1) "Set & forget" necessitates the CO2 regulator being left open for the whole time generally in the order of 2 - 3 weeks. This is OK but only when the brewer is certain that his/her system has no leaks. In my case I tested for leaks (very thoroughly I thought), but lost all my CO2 gas over a few days due to a minute leak. Finally able to detect it only after putting the pressurised keg into my swimming pool!!
CO2 is not low cost & I never now leave the regulator permanently on.
I start force carbing at 50 psi & re-pressurise at about 2 day intervals until the gas uptake slows when I reduce the pressure to about 20 psi & repressurise then at about 3 day intervals. Soon things come to equilibrium & in my case I settle around 8 psi.
2) Remember that a "full" keg has only a relatively small "airspace" so pressurising to 50 is not actually introducing very much gas. By the same reasoning you will find that only a few glasses dispensed from a new keg (with regulator shut) will result in the keg pressure falling to as little as 2 to 4 psi & the dispensing rate will fall quickly.
Possibly a good idea to allow the regulator to remain open, but set at a lower (than 8 psi) pressure during "dispensing". I say that because I find 8 psi is too high for dispensing in my case despite quite long lines.
An excellent & simple answer to the often asked question of newcomers to carbing.
Addressing particularly newcomers, I think several additional points are worth making:
1) "Set & forget" necessitates the CO2 regulator being left open for the whole time generally in the order of 2 - 3 weeks. This is OK but only when the brewer is certain that his/her system has no leaks. In my case I tested for leaks (very thoroughly I thought), but lost all my CO2 gas over a few days due to a minute leak. Finally able to detect it only after putting the pressurised keg into my swimming pool!!
CO2 is not low cost & I never now leave the regulator permanently on.
I start force carbing at 50 psi & re-pressurise at about 2 day intervals until the gas uptake slows when I reduce the pressure to about 20 psi & repressurise then at about 3 day intervals. Soon things come to equilibrium & in my case I settle around 8 psi.
2) Remember that a "full" keg has only a relatively small "airspace" so pressurising to 50 is not actually introducing very much gas. By the same reasoning you will find that only a few glasses dispensed from a new keg (with regulator shut) will result in the keg pressure falling to as little as 2 to 4 psi & the dispensing rate will fall quickly.
Possibly a good idea to allow the regulator to remain open, but set at a lower (than 8 psi) pressure during "dispensing". I say that because I find 8 psi is too high for dispensing in my case despite quite long lines.
Just the tread I was looking for. I have a kegerator and would like to have one batch on tap and a second carbonating. Pretty sure I have room for both to chill but I can't currently have them both hooked to the co2. Surely there are several ways to go about this. Not too concerned with a two week wait. Any thoughts would be appreciated.
You need 2 regulators if you want to put different pressure on 2 kegs. If you don't mind them being the same pressure, then all you need to do is split your current CO2 line. Either with fancier pre-built splitters with separate shutoff valves, or simply splice a "T" into your current line and run another with it's own QD on the end
jeepinjeepin
Well-Known Member
wilsojos said:
This. I don't force carb, but I wish I had a dual regulator so I could leave one turned up to seat lids or carb at room temperature.
Yes, it's quite handy.
My setup is 2 regulators on the outside of the keezer with the lines running thru the collar to separate CO2 splitters inside.
Also, one of the regulators has a "Y" on the output so one line goes into the keezer, and the other is a separate CO2 line with QD.
When it comes time for kegging a batch, it's really nice to have that separate "outside line" for purging kegs, sealing lids, getting a "head start" on carbing a keg on the outside when there isn't room for another keg on the inside, etc. Simply turn off the valve that feeds the keezer and then the exterior line is free to do whatever you want without screwing up your kegs inside the keezer.
And being able to run different pressures on different kegs inside is nice too
wobdee
Junior Member
Whew! What a thread, lots of great info and different techniques. I may of missed it but I have 4 ea 2.5 gal kegs and have been doing nat carb for the last few months but now I'm switching to force carb.
Can I still follow the co2 charts with a smaller 2.5 gal keg or are these charts for the standard 5 gal kegs?
I like the idea of set and forget but with 4 kegs in line in my fridge I don't think I would want 4 seperate gas lines and extra hardware, just seems like too much trouble.
My plan is to cold crash, pick co2 from chart, roll till carbed and throw it back in fridge for about a week or when it's next in line. This way I only need one gas line with one regulator. How does this sound? Thanks
Can I still follow the co2 charts with a smaller 2.5 gal keg or are these charts for the standard 5 gal kegs?
I like the idea of set and forget but with 4 kegs in line in my fridge I don't think I would want 4 seperate gas lines and extra hardware, just seems like too much trouble.
My plan is to cold crash, pick co2 from chart, roll till carbed and throw it back in fridge for about a week or when it's next in line. This way I only need one gas line with one regulator. How does this sound? Thanks
jeepinjeepin
Well-Known Member
DustBow said:
Mine, as I've said, is a single reg. It will become part of the travel rig when I upgrade to a dual. I have a T on the outside and a 4 way manifold inside. Of course they are all running 12-14 psi, limiting my ability inside, but especially outside the fridge.
DustBow said:
Thx! Think I've got my plan set. Please confirm and/or poke holes in what follows:
I will buy a second QD, a splitter with shutoffs and more tubing (length?). I'll have both kegs always attached and set the regulator to serving psi (when/why would I want a second regular to push different psi?). I'll leave the carbonating keg chilling with the drinking keg in the kegerator for two weeks or longer before drinking.
Thanks
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Just be sure that the shutoffs have check valves (most do). The length of the gas line doesn't matter. Give yourself enough extra to be able to move the kegs around if you have to.
Opinions will vary but I would just wait until you have your co2. Right now your beer has a nice layer of co2 protecting it but when you move it to the corny that will be gone if yoy can't purge the oxygen.
jeepinjeepin
Well-Known Member
Laoz said:
Kealia said:
As long as you haven't cold crashed it you can rack it and add priming sugar. Personally, I would wait.
I was able to find co2 yesterday after all! $30 to swap out a 2.5lb tank can't be my best option going forward tho. My first batch, an ipa, tasted good! Racked and brewed a porter. Rolling! Think I'll need to rig a bigger co2 outside my kegerator to get this 2 keg plan setup for long term use. Alls well. Thx for for advice.
BigB
Well-Known Member
Ouch... That is steep. I pay around $20 to swap out a 20# tank. Heck a 5# tank at my LHBS (which is always higher than everyone else for gas) is only $14.
My kegerator also came with a 2.5 lb tank. I am just barely able to fit a 5 lb tank inside of it now. I just keep my 2.5 lb tank full in case I run out of gas at a bad time and need to use it.
Well I have my 5 lb tank sit on the back ledge of my Frosty Keg kegerator. The tank measures 18" tall and with the regulator dials they add about 1.5" taller than the tank. So if you go atleast 20" of vertical clearance from the ledge to the ceiling then I'd say you are fine. Hope that helps!
I've made it up to page 48 and my eyes are crossed!
Was wondering this... if the patient method required 2 weeks of waiting and this can be done at room temperature, can the last 2 weeks of secondary conditioning be performed in the keg while it's carbonating at room temp (ie; 68-70°)?
Scenario; I've racked from primary to secondary after 1 week. Beer has been in secondary for 1 week and a little more settlement has appeared, but not much.
If it's possible to finish out the conditioning in the keg, I understand that I might have some sediment in the bottom--I can simply discard a pint.
Can I condition and carbonate at the same time?
Was wondering this... if the patient method required 2 weeks of waiting and this can be done at room temperature, can the last 2 weeks of secondary conditioning be performed in the keg while it's carbonating at room temp (ie; 68-70°)?
Scenario; I've racked from primary to secondary after 1 week. Beer has been in secondary for 1 week and a little more settlement has appeared, but not much.
If it's possible to finish out the conditioning in the keg, I understand that I might have some sediment in the bottom--I can simply discard a pint.
Can I condition and carbonate at the same time?
Yes you can. However, some of the clean up for by the yeast during conditioning is more efficient at higher temperatures, leading to a more rounded beer faster. But if you're in a hurry to get the beer on tap, you can hook er up.
You can cold crash the beer before transferring to the keg in order to minimize the trub in the keg. 2 days in the fridge should be good to get most of it dropped out
You can cold crash the beer before transferring to the keg in order to minimize the trub in the keg. 2 days in the fridge should be good to get most of it dropped out
"However, some of the clean up for by the yeast during conditioning is more efficient at higher temperatures"
right... in the query; "and this can be done at room temperature, can the last 2 weeks of secondary conditioning be performed in the keg"
Is room temperature considered "higher temperature". I'm trying to figure out if I can combine the two procedures into one at room temperature. Sorry if my question was poorly asked but with the "however" stipulation in the reply lead me to believe that I may have misconstrued my thoughts..
right... in the query; "and this can be done at room temperature, can the last 2 weeks of secondary conditioning be performed in the keg"
Is room temperature considered "higher temperature". I'm trying to figure out if I can combine the two procedures into one at room temperature. Sorry if my question was poorly asked but with the "however" stipulation in the reply lead me to believe that I may have misconstrued my thoughts..
Sorry, I misread your post. I thought you were asking if you could do this all in the fridge despite your temperature statements! Stupid me.
Yes you can do that. Since my CO2 is in my keg fridge, i would need to chill and carb my beer at the same time as try need to be hooked up for the entire process. This is where my temperature and conditioning time comes in to play.
The additionally pressure shouldn't have a significant impact on conditioning, so you're fine to go ahead and do that. Sorry about the misinterpretation'
Cheers
Yes you can do that. Since my CO2 is in my keg fridge, i would need to chill and carb my beer at the same time as try need to be hooked up for the entire process. This is where my temperature and conditioning time comes in to play.
The additionally pressure shouldn't have a significant impact on conditioning, so you're fine to go ahead and do that. Sorry about the misinterpretation'
Cheers
OP
OP
I don't think this is correct. Given adherence to the chart for the exact same volumes of CO2, physics says the warmer beer should reach equilibrium faster than the cold beer.
StMarcos
Well-Known Member
Yup. Diffusion is faster when the system is warmer.
True but if you are boost carbing then cold is better
StMarcos
Well-Known Member
What's boost carbing?
Hi pressure low temp for a short period of time.
It is true that diffusion is faster given the same pressure and a higher temp. But also the required pressure for a given volume of CO2 is lower for lower temp. So if you doing it properly you can boost carb to 80% of the deaired vols overnight. At a low temp and high pressure.
The system can only handle a certain max pressure. That max press sure packs more of a punch at low temp
AVLbrewing
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Hey Guys,
I have a few quick questions that someone can hopefully answer (and I assume have already been answered here). Sorry for the lack of foresight in planning on my part but I'd like to get my first keg up and running by Saturday if at all possible. Obviously I'd need to do the burst carb method at this point. So here goes:
1) Right now I'm using a full size fridge without a temp controller. I actually just got one in the mail today, but I'm not sure if I'll have time to get it up and running before I need to start kegging. Should I take the average temperature in my fridge when calculating carbonation rate? For example:
Min Temp: 34F
Max Temp: 43F
Avg Temp: 38.5F
The only issue with this method is that this assumes that it spends equal amounts of time. I guess this temperature could also be considered the "median" temperature. Either way, how should I go about planning my CO2 volumes until I can get it properly regulated?
2) Assuming we go for 38.5F and I want 2.5 volumes of CO2 (for a Cream Ale), I'd set the PSI to approx 3 time the level listed in the chart (12psi x 3 = 36psi) for 24hrs, purge the head space, then set the regulator to 12psi. That gets me to Saturday when I'd like to serve. Would it be ok to serve then at 12psi or do I drop the pressure further to a lower serving pressure, and if so how do I calculate that? Is that based off of keg line lengths? This is all assuming no shaking of the keg. Would I need to do some sort of shaking and adjustments to my original psi calculations?
3) I'll be dispensing from a picnic tap with a super short line length. I assume is close to 3.5', and everything I've read said that I should get a much longer length of line. Is there anyway that I could serve from this? If not I can make a run down to the LHBS and pick up a 10' line.
Thanks for helping out. I'll hopefully start getting this carbed up as soon as possible, so any quick responses would be greatly appreciated. I don't know what I'd do without you fine folks here at HBT!
Cheers!
I have a few quick questions that someone can hopefully answer (and I assume have already been answered here). Sorry for the lack of foresight in planning on my part but I'd like to get my first keg up and running by Saturday if at all possible. Obviously I'd need to do the burst carb method at this point. So here goes:
1) Right now I'm using a full size fridge without a temp controller. I actually just got one in the mail today, but I'm not sure if I'll have time to get it up and running before I need to start kegging. Should I take the average temperature in my fridge when calculating carbonation rate? For example:
Min Temp: 34F
Max Temp: 43F
Avg Temp: 38.5F
The only issue with this method is that this assumes that it spends equal amounts of time. I guess this temperature could also be considered the "median" temperature. Either way, how should I go about planning my CO2 volumes until I can get it properly regulated?
2) Assuming we go for 38.5F and I want 2.5 volumes of CO2 (for a Cream Ale), I'd set the PSI to approx 3 time the level listed in the chart (12psi x 3 = 36psi) for 24hrs, purge the head space, then set the regulator to 12psi. That gets me to Saturday when I'd like to serve. Would it be ok to serve then at 12psi or do I drop the pressure further to a lower serving pressure, and if so how do I calculate that? Is that based off of keg line lengths? This is all assuming no shaking of the keg. Would I need to do some sort of shaking and adjustments to my original psi calculations?
3) I'll be dispensing from a picnic tap with a super short line length. I assume is close to 3.5', and everything I've read said that I should get a much longer length of line. Is there anyway that I could serve from this? If not I can make a run down to the LHBS and pick up a 10' line.
Thanks for helping out. I'll hopefully start getting this carbed up as soon as possible, so any quick responses would be greatly appreciated. I don't know what I'd do without you fine folks here at HBT!
Cheers!
chuckstout
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Im sure someone will give you a proper answer, but this is mine
1. Taste it after your day of quick carbing (36psi)and degassing, you well be able to tell whats right by taste.
2. You should either get a longer line(+) or try 8-10psi to see if that works.
3. Drink up and cheers!
1. Taste it after your day of quick carbing (36psi)and degassing, you well be able to tell whats right by taste.
2. You should either get a longer line(+) or try 8-10psi to see if that works.
3. Drink up and cheers!
Check out this BYO article about balancing your system. http://byo.com/kegging/item/164-balancing-your-draft-system-advanced-brewing
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