Force carbing in a corny keg

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logdrum

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sivdrinks said:
If you can over carb beer how comes it doesn't over carb when you set it and forget it? If the answer is beer can only absorb so much co2 then how can it be over carbed doing the other methods?
Because your "set it" pressure was (hopefully) assigned according to temperature and eventual volumes of CO2. Beer is able to"absorb" more CO2 than we'd typically like, so at a higher psi more CO2 is dissolved in the beer.
 

sivdrinks

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As far as the gauge goes, it must mean something. Mine went from 850 to 450 in less than a week. The fresh fill before that didn't even last me a 3 gallon keg. Do I have a bad bottle? Soapy water found zero leaks.
 

Homercidal

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As far as the gauge goes, it must mean something. Mine went from 850 to 450 in less than a week. The fresh fill before that didn't even last me a 3 gallon keg. Do I have a bad bottle? Soapy water found zero leaks.
There must be something. I have lost pressure due to a QD losing pressure when it got cold enough. I just replaced it and so far so good.

When you start with a warm tank, the CO2 is less dense and therefore takes up a greater volume. A greater volume means higher pressure.

When you then chill it down, it is more dense and has less volume and lower pressure. So some of your pressure loss might have come from being chilled in the kegereator (if you keep it in the kegerator)

But that's a lot of pressure loss, so I suspect a leak somewhere in the system.

Do you use teflon tape on all the threaded fittings?
 

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Yooper said:
I don't agree with overcarbing and then turning it down. That seems unnecessary to me. If you have a fridge, set it at 10-12 psi and let it sit for a week. After a week it should be just about perfect!
This its the only way if you ask me...unless you enjoy foam...
 

sivdrinks

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Homercidal said:
There must be something. I have lost pressure due to a QD losing pressure when it got cold enough. I just replaced it and so far so good.

When you start with a warm tank, the CO2 is less dense and therefore takes up a greater volume. A greater volume means higher pressure.

When you then chill it down, it is more dense and has less volume and lower pressure. So some of your pressure loss might have come from being chilled in the kegereator (if you keep it in the kegerator)

But that's a lot of pressure loss, so I suspect a leak somewhere in the system.

Do you use teflon tape on all the threaded fittings?
I got my stuff from Keg Connection, not sure I'd order there again. Lots of mistakes with my order. I'll have to double check the tape, I did a soapy water test on the regulator and found nothing. The two kegs I've carbed I did the shake method, not sure if that matters. I'm also getting my bottle filled instead of exchanged, not sure they're doing it right either.
 
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aaronc5150

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Of all these ways mentioned, whether its the "hurry up" or the "patient" method, do you always use the line in connector or do you use the liquid out connector? Is one better than the other and is there any "risks" if you use the liquid out connector? Thanks.
 

logdrum

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The posts are slightly different. G-gray for Gas, B-black for Beer. You can force the wrong one on, but it messes up the disconnect.

Sent from my iPod touch using HB Talk
 
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aaronc5150

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I don't agree with overcarbing and then turning it down. That seems unnecessary to me. If you have a fridge, set it at 10-12 psi and let it sit for a week. After a week it should be just about perfect!
Yooper - when doing this, do I hook up the C02 to the "gas in (gray)" connector and not the "liquid out (black) connector like I have seen others suggest? And I am assuming with this method you mention there is no shaking of the keg after hooking up CO2? Thanks!
 

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Yooper - when doing this, do I hook up the C02 to the "gas in (gray)" connector and not the "liquid out (black) connector like I have seen others suggest? And I am assuming with this method you mention there is no shaking of the keg after hooking up CO2? Thanks!
I just hook it up correctly- with the gas into the gray connector. The theory with putting it on the "out" line is that it will bubble through the gas, and so make the carbonation faster. I don't think that works very well, as the bubbles are pretty big and would just bubble up through the beer anyway.

If you wanted to try something like that, I"d recommend a carbonation stone. It's an airstone, like for aquariums or o2 set ups, that diffuses the gas through a solution. I think Brewpastor talked about using one a few years ago, and liked the result. For me, I just hook up the keg in the fridge, leave it 36 hours and purge and reset down to 12 psi.
 
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aaronc5150

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Ok, ya I will just hook it normally to the "in" connector. So after its kegged and cold, just hook it up at the desired PSI (10-12) and let it sit, without shaking it at all?
 

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Ok, ya I will just hook it normally to the "in" connector. So after its kegged and cold, just hook it up at the desired PSI (10-12) and let it sit, without shaking it at all?
I hook mine up warm, but yes, you can just let it sit if you're a patient soul! It'll be ready in about a week in the fridge at 12 psi.
 

JuanMoore

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I just hook it up correctly- with the gas into the gray connector. The theory with putting it on the "out" line is that it will bubble through the gas, and so make the carbonation faster. I don't think that works very well, as the bubbles are pretty big and would just bubble up through the beer anyway.

If you wanted to try something like that, I"d recommend a carbonation stone. It's an airstone, like for aquariums or o2 set ups, that diffuses the gas through a solution. I think Brewpastor talked about using one a few years ago, and liked the result. For me, I just hook up the keg in the fridge, leave it 36 hours and purge and reset down to 12 psi.
+1
The agitation from the giant bubbles coming through the beer is actually counterproductive since it knocks existing C02 out of solution. Pushing CO2 through the out diptube while purging pressure is actually a very quick way to degas an overcarbed keg.
 

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Hi, all -

I'm just now carbing up my first Corney keg, and I'm doing it at room temperature of 67 degrees. Per my carbbing chart, to get 2.5 volumes of CO2, I need to be at 31 psi. I'm using the "set and forget" method - but I have a few questions:

1. Should I expect the Corney keg's gauge to slowly decrease over the next two weeks? I set it per my chart at 31 psi, should I expect it to hold at 31 psi the full two weeks, or will it gradually drop?

2. Once two (or even three) weeks has gone by, do I just lower it to serving pressures (5-10 psi depending on length of beer line, or do I shut the pressure off, bleed it out, and THEN reset it at serving pressures?
 

JuanMoore

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Hi, all -

I'm just now carbing up my first Corney keg, and I'm doing it at room temperature of 67 degrees. Per my carbbing chart, to get 2.5 volumes of CO2, I need to be at 31 psi. I'm using the "set and forget" method - but I have a few questions:

1. Should I expect the Corney keg's gauge to slowly decrease over the next two weeks? I set it per my chart at 31 psi, should I expect it to hold at 31 psi the full two weeks, or will it gradually drop?

2. Once two (or even three) weeks has gone by, do I just lower it to serving pressures (5-10 psi depending on length of beer line, or do I shut the pressure off, bleed it out, and THEN reset it at serving pressures?
1. The entire job of the regulator is to keep the pressure constant. If it drops, you either have a faulty regulator or a leak and an almost empty CO2 tank.

2. Assuming you'll be putting the keg in a fridge/keezer or somehow chilling it before serving, you'll want to adjust the pressure to correspond to the new temperature. Use the same chart you used to find the original pressure. If you set it at a different pressure, it will slowly gain or lose carbonation accordingly. The serving/carbonating pressure is not at all dependent on line length. It's the line length that's dependent on the pressure.

You can either disconnect the gas, chill the keg, then reconnect at the lower pressure, or turn off the gas, purge the keg, turn the gas back on at the lower pressure, and then start chilling it.
 

chrismontgomeryil

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1. The entire job of the regulator is to keep the pressure constant. If it drops, you either have a faulty regulator or a leak and an almost empty CO2 tank.

2. Assuming you'll be putting the keg in a fridge/keezer or somehow chilling it before serving, you'll want to adjust the pressure to correspond to the new temperature. Use the same chart you used to find the original pressure. If you set it at a different pressure, it will slowly gain or lose carbonation accordingly. The serving/carbonating pressure is not at all dependent on line length. It's the line length that's dependent on the pressure.

You can either disconnect the gas, chill the keg, then reconnect at the lower pressure, or turn off the gas, purge the keg, turn the gas back on at the lower pressure, and then start chilling it.
I figured if I carbed it at room temperature (67 degrees ) for the appropriate length of time (2 weeks), then disconnected the gas line, whether I chilled the beer or not, I thought it would keep the same volumes of CO2 in the beer - that is, once the beer has been infused with the proper volume of CO2, the temperature the beer is stored at later shouldn't matter (i.e. I thought volumes of CO2 are constant once dissolved into the beer).

If I understand you correctly, you're saying that if I carb the beer at 67 degrees for a set amount of volumes of CO2, then disconnect the CO2 line and chill the beer, that my volumes of CO2 will change.

Though I'm understanding your comment about line length, I will certainly check out the proper serving pressures vs. line length prior to serving the beer.
 

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I figured if I carbed it at room temperature (67 degrees ) for the appropriate length of time (2 weeks), then disconnected the gas line, whether I chilled the beer or not, I thought it would keep the same volumes of CO2 in the beer - that is, once the beer has been infused with the proper volume of CO2, the temperature the beer is stored at later shouldn't matter (i.e. I thought volumes of CO2 are constant once dissolved into the beer).

If I understand you correctly, you're saying that if I carb the beer at 67 degrees for a set amount of volumes of CO2, then disconnect the CO2 line and chill the beer, that my volumes of CO2 will change.

Though I'm understanding your comment about line length, I will certainly check out the proper serving pressures vs. line length prior to serving the beer.
Not at all- dissolved co2 is dissolved co2, so the volumes of c02 will be correct. What MIGHT be an issue is any c02 still in the headspace- you don't want 30 psi for example backing up any beer into the regulator when it's chilled and you set for the lower psi. Does that make sense? You purge so you don't have that problem, and then simply set it at the lower psi for the temp in the kegerator.
 

JuanMoore

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I thought it would keep the same volumes of CO2 in the beer - that is, once the beer has been infused with the proper volume of CO2, the temperature the beer is stored at later shouldn't matter (i.e. I thought volumes of CO2 are constant once dissolved into the beer).

The carbonation level is not constant, it is dependent on temperature and pressure. If you're just storing the beer, then you are correct that the carbonation will remain constant if you disconnect the gas regardless of temperature. The pressure in the headspace will change as temperature changes, but it will stay at 2.5 vol since the gas has nowhere to go. I assume however that you plan on serving this keg at some point, and the first time you pour a pint the headspace pressure will change. It's not an instant thing, but the carb level will eventually reach equilibrium with whatever the headspace pressure is set to, which is why the serving pressure needs to be set according to your desired carbonation level. If you carb to 2.5 vol, but then put the beer on only 5 psi at 40F, the carb level will eventually drop to 1.83 vol (according to the chart). Likewise keeping the beer at 32F and 12 psi will result in 2.9 vol after a few days. You've carbonated your beer to 2.5 vol, and if you want to keep it at that level as you serve it, then you need to set the serving pressure to correspond with that carb level at your beer temp. At 42F you need 13psi, at 38F you need 11psi.

Once you know your desired carbonation level and beer temperature, you can use the chart to set the serving pressure. Once you know the serving pressure, you can then determine how long your beer lines should be to provide proper resistance to counter that pressure and get a good pour.

Hope this helps.
 

JuanMoore

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Not at all- dissolved co2 is dissolved co2, so the volumes of c02 will be correct. What MIGHT be an issue is any c02 still in the headspace- you don't want 30 psi for example backing up any beer into the regulator when it's chilled and you set for the lower psi. Does that make sense? You purge so you don't have that problem, and then simply set it at the lower psi for the temp in the kegerator.
Correct, but I don't think they understand that the serving pressure will affect the carbonation level.
 
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