Does the 30 PSI over 48 hours carb method waste more gas?

CornyKegs 728
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bearcamp

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So my first CO2 tank which is 5lb kicked over the weekend. It so far has last 4 kegs of carbing and serving. Still have about a gallon or less left on keg 3 & 4. I have read that a 5lb tank should last more than 4 kegs usually around 7-10. I have a two regulator kit and my method is to carb at 30 PSI for 2 days then bring the PSI down to 10-12.

Does this method of carbing waste more gas? If so I'll definitely move to the set it and forget it method. I don't think it is a leak as I hooked up a friends CO2 tank to check with soapy water. It may also be I played around with the first two kegs making sure the keg was keeping presure and purging the air as sometimes the PSI would get higher than what I set it. Plus I've used some gas to clean and sanitize the lines.

Any help or suggestions.

Thanks
 
No, it doesn't use more gas.

The only way using 30psi would use more gas than 12psi, is if you left it at that level too long and ended up carbing at a higher carb level than 12psi would have given in the long run.
 
SouthernCross said:
Yes, without doubt.[...]
Click to expand...

Ok, color me Curious. Why would that be the case?

I don't do the burst-carb thing, but I'm having trouble understanding why it would "waste" gas compared to just setting serving pressure on the keg and letting it carb up over a couple of weeks.

Leaving aside the multitudes of over-carbed scenarios so often related here, if both methods result in the same volume of CO2, how could either method be more efficient in the use of the gas?

Cheers!

[edit] Wow - in the time it took me to type that, the proposition has already been contested twice ;)
 
Bs, the same amount of o2 is used in carbing a keg however you do it. why/how would one method use more? I suspect it's the venting and the repressurizing to push cleaning solution that is using the gas.
-cheers
 
Im also using this method and I hate to thread jack, but do any of you shake the keg when carbing at 30 psi?
 
Ah thanks for the info ill just leave it be.....I'm sure 48hours at 30psi is plenty of carb
 
AnOldUR said:
Only if you over carb and have to vent.
Click to expand...

this.

2 volumes is 2 volumes, doesnt matter if you get there at 12psi slowly, or 30psi quickly and then reduce pressure. its the same volume of CO2.

you only waste it if you overshoot and have to vent some.
 
if your not venting the co2 off then you are not using any more gas with 48hr overpressure, or 5 minute shake method or target level over 5 days. the same amount of co2 will dissolve into solution to get your target carb level
 
I run 30 psi at 72 hours. 48 and it is no where near carbed (I carb almost everything to 2.6 vol./CO2. You are expelling CO2 into another sealed vessel. There is nothing "waisted" you just run the risk of the beer absorbing more than the desired amount of CO2.
 
Aksig88 said:
Im also using this method and I hate to thread jack, but do any of you shake the keg when carbing at 30 psi?
Click to expand...

Nope - but I DO shake it at 12psi, or whatever psi is required to achieve a given volume of co2, based on the temperature of the beer.

It takes about 5 minutes or so of shaking until the regulator stops dumping into the keg. Once that's done, put it in the refrigerator at the same psi, and let it sit for several hours, and it's ready to drink.

Shaking at 30psi is unnecessary and is a recipe for overcarbing.
 
AnOldUR said:
Only if you over carb and have to vent.
Click to expand...

So every one of you is saying that from the very first time you force carbed, you never bled any off? Cmon. Don't be so quick to disagree with everyone.
If OP is trying this technique, chances are he's going to bleed some off. And again, if his keg isn't cold, he'll use more when he hits it, cooling the beer before it carbs.
Sheesh. Present people with real-world advice, not best-case scenario.

Again I'll say then, that yes, when you try this method, you'll end up using more gas. But the tradeoff will be beer that's carbed and ready to drink in a couple days. You won't use half a bottle more gas, but if you do a few kegs worth, it adds up.
 
AnOldUR said:
Only if you over carb and have to vent.
Click to expand...

SouthernCross said:
So every one of you is saying that from the very first time you force carbed, you never bled any off? Cmon. Don't be so quick to disagree with everyone.
If OP is trying this technique, chances are he's going to bleed some off. And again, if his keg isn't cold, he'll use more when he hits it, cooling the beer before it carbs.
Sheesh. Present people with real-world advice, not best-case scenario.

Again I'll say then, that yes, when you try this method, you'll end up using more gas. But the tradeoff will be beer that's carbed and ready to drink in a couple days. You won't use half a bottle more gas, but if you do a few kegs worth, it adds up.
Click to expand...

I think everyone agreed with AnOldUR, and I think you do too. OP admitted to purging / venting, so that's where the extra gas went. Hey, everybody's correct!
 
Yeah, I gotcha. But some of the responses here are akin to telling someone that fermenting in buckets is 'wrong'. Or 'no one' uses secondary anymore. We all know there are different techniques, and different methods.

Why everyone has to be so quick to disagree eludes me. Bah...
 
People tend to disagree because some answers are blatantly incorrect, somewhat incorrect or "it depends based on these other factors you didn't mention". He described a method that MAY use more gas "if you do a lot of venting" but otherwise does NOT. Your answer was "absolutely without a doubt" and that was incorrect because you didn't know if the OP does any venting along with the elevated pressure process. The weird thing is that your first post was a definitive answer and your last post was criticizing posts that espouse definitive answers.


Bottom line, there are methods to conserve gas no matter what your carb method is. To the OP's question, You don't HAVE to vent the gas just because you held the regulator at 30 psi for 2 days. You can disconnect the gas QD, drop the pressure to 12psi, and then let the 30psi headspace dissolve overnight before hooking the QD back up.
 
jvcjbl said:
I run 30 psi at 72 hours. 48 and it is no where near carbed (I carb almost everything to 2.6 vol./CO2. You are expelling CO2 into another sealed vessel. There is nothing "waisted" you just run the risk of the beer absorbing more than the desired amount of CO2.
Click to expand...

I've run 30 PSI for less than 3 days and overcarbed.

It's important to note that charging a cold keg will give different results than charging a warm keg. Cold kegs accept more CO2 and faster.
 
Bobby_M said:
People tend to disagree because some answers are blatantly incorrect, somewhat incorrect or "it depends based on these other factors you didn't mention". He described a method that MAY use more gas "if you do a lot of venting" but otherwise does NOT. Your answer was "absolutely without a doubt" and that was incorrect because you didn't know if the OP does any venting along with the elevated pressure process. The weird thing is that your first post was a definitive answer and your last post was criticizing posts that espouse definitive answers.


Bottom line, there are methods to conserve gas no matter what your carb method is. To the OP's question, You don't HAVE to vent the gas just because you held the regulator at 30 psi for 2 days. You can disconnect the gas QD, drop the pressure to 12psi, and then let the 30psi headspace dissolve overnight before hooking the QD back up.
Click to expand...

Yup, rereading what I posted you're dead-on. Heh. I was the person I was just complaining about! Ah, must've been sleepy or lazy when I posted...
 
So I am new to this kegging / force farb thing. Last night I placed my Lager in a cold keg. I placed a little Co2 to push the O2 out. Then I put in 30 psi in the keg then I disconnected the Co2 line, shook, and placed it in the fridge. Do I have to bleed it before hooking back up my regulator and Co2 before I place it on serving pressure?

*Note* When I shook it I did not hear "hissing" or "bubbling" did I do it correctly?
 
When you hook up the gas line again, if the pressure gauge goes up past your serving pressure, just bleed a bit then re-connect. Do it again if needed to equalize to your serving pressure.
MOst times you shake while gas line is connected so that more gas enters keg during shaking. And gas enters cold beer much better. Might not be a bad idea to do it again now that beer is cold. Connect gas, set to 30 psi. Shake until hissing stops. Then disconnect and chill for a couple days...
 
SouthernCross said:
. . . now that beer is cold. Connect gas, set to 30 psi. Shake until hissing stops. Then disconnect and chill for a couple days...
Click to expand...
But not so sure about this.

If you shake chilled beer with the CO2 hooked up at 30PSI until it stops hissing, I'd think that you just carbed you beer to 30PSI.


edit to say:
I personally don't shake.
But if I did it would be at serving pressure.
 
@Bobby - No worries, you were right and I didn't read it snarky.

@AnOldUR - maybe that's why I bleed off more then? That's the way I read/learned. Your comment makes sense for sure. So you wouldn't roll/shake, or wouldn't do so at 30PSI?
 
SouthernCross said:
So you wouldn't roll/shake, or wouldn't do so at 30PSI?
Click to expand...
There's really no wrong way as long as it ends up with beer at the proper serving pressure.

Personally, after transfer I put the (not yet chilled) keg in the fridge at 30+ PSI for 24 to 48 hours and then drop the pressure back to serving. No venting. No shake or roll. It's usually ready to tap a few days after that. Sometimes sooner.





Edit to say:
That's if I need the beer. Most of the time I'll leave it set outside the fridge at 30+ PSI for 24 to 48 hours and then disconnect and store at basement temperatures.
 
SouthernCross said:
When you hook up the gas line again, if the pressure gauge goes up past your serving pressure, just bleed a bit then re-connect. Do it again if needed to equalize to your serving pressure.
MOst times you shake while gas line is connected so that more gas enters keg during shaking. And gas enters cold beer much better. Might not be a bad idea to do it again now that beer is cold. Connect gas, set to 30 psi. Shake until hissing stops. Then disconnect and chill for a couple days...
Click to expand...


Nope - not a good idea to do that.

Shaking a cold keg at 30psi is going to significantly overcarb and waste gas.

If you shake a cold keg, then it should be done at 12psi, or the required psi for the desired volume, until the regulator stops dumping into the keg. This will carb it exactly to the desired co2 volume and it won't overcarb or waste any gas. Once the foam dies down, it's ready to drink.
 
Gotcha. I merged both methods there. I typically do mine directly after filling, then purge and charge, roll just a bit, then put in kegerator for a few days.
 
SouthernCross said:
Gotcha. I merged both methods there. I typically do mine directly after filling, then purge and charge, roll just a bit, then put in kegerator for a few days.
Click to expand...
If your into the shake or roll thing, that's not a bad method. 30 PSI at room temperature is just about right for serving volumes.
 
Hmm. Unfortunately I'm into instant gratification! The final step of waiting to drink just kills me... Shaking seems a bad thing to do, but I guess as long as I purge first it's ok. I usually roll it a few times on my lap, but that's it. I frequently put some in a tap-a-draft when i keg, and just crank a couple co2 cartridges in it so I can taste test while the keg gets going...
 
Ok, So that I understand, when I get home I'll check the keg. The beer was cold when I charged it @ 30 psi and shook. I should bleed some out until it hits serving pressure right? I just want fast carbing brew. No more two week waits like bottling. The advice on the forums are so back in forth its sometimes harder to understand whats being said.
 
I'd only shake the keg if I were in a huge hurry. And I'm not. The set and forget method is foolproof. It's not worth it to have to vent and degas from overshooting. Unless I had a party or competition that would require my beer in less than 14 days.
 
RandomBeerGuy said:
The beer was cold when I charged it @ 30 psi and shook. I should bleed some out until it hits serving pressure right?
Click to expand...
Here's the problem with shaking. If you over carb there's too much CO2 in solution. You can vent the head space, but that will only allow a small amount of gas to be released. After that, more CO2 will come out of solution until equilibrium is reached between the liquid and head space. You will still have over carbed beer. It may take repeated venting over several days to correct the situation.

So the effort to speed up the process can actually slow it down.
 
AnOldUR said:
Here's the problem with shaking. If you over carb there's too much CO2 in solution. You can vent the head space, but that will only allow a small amount of gas to be released. After that, more CO2 will come out of solution until equilibrium is reached between the liquid and head space. You will still have over carbed beer. It may take repeated venting over several days to correct the situation.

So the effort to speed up the process can actually slow it down.
Click to expand...


Yup - at 30psi, shaking will prob overcarb.. but you CAN'T overcarb if you simply set it to the required psi, which is usually 10-12psi or so. I would never shake it at higher than the required pressure.

If the beer is cold, then you shake at 12psi until the regulator stops filling. At that point, the beer is carbed to the perfect pressure. You then just set it aside for several hours until the foam dies down. Keep it hooked up and at 12psi the whole time.
 
For what it's worth here's how I force carb..(And I just got done doing 3)
Say I want 2.47 volumes and by beer is 40 degrees that would be about 12 lbs..
I set regulator for 30 psi and shake , roll, push ,kick, etc..for 20 mins..
then I shut the co2 valve off and continue to shake. The high pressure gauge will drop off to zero then the low pressure gauge will begin to drop. If you keep shaking and it stops at 10 lbs ya need a little more, if its at 12, your done.
It takes a little getting used to but it works for me.
The co2 bubbles may be a little large at first but I set the serving pressure to the volumes I want ,depending on how cold kegerator is, and in a day or 2 it's perfect.
 

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