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Storing kegs without constant c02 pressure

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beervoid

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I've got the following situation.

I've got a fridge to cold crash and store my beers before I move them to my kegerator where I can connect them to constant co2 pressure.

I've got co2 available at the "cold crash fridge" but I can only keep 1 keg connected at the time.
What i'm doing now is every morning and evening I top it up to about 20psi. This usually drops to about 15-12 psi by the time I check again.

This seems to make sure the kegs keep sealed but it is kind of tedious so im looking for possible solutions and suggestions to perhaps do this another way.
Force carbonating is not an option as I got all loose hops in the kegs.

How long do I need to keep topping up?
Will my beer not be over carbonated at some point?

Cheers!
 

Moose_MI

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My 2 cents ...... if you’re just storing them in your fridge then I wouldn’t worry about topping them off.

If you’re trying to carb the beer that’s in their that’s going to be tedious w/o co2 setup in that fridge.

Yes, i would assume you will over carb but I’ve never done what you’re doing. Not even sure i can offer a guess as to how long before that might happen.
 
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beervoid

beervoid

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Carbing and cold crashing at the same time.

On that note if I get co2 splitter how many kegs can I carbonate at the same time?
 

Vale71

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Force carbonating is not an option as I got all loose hops in the kegs.
Actually, force carbonating is what you are doing to those kegs. The reason the pressure drops is because CO2 is migrating to the beer thus increasing carbonation. If beer is already properly carbonated and the kegs are in good working condition (i.e. no leaks) then you don't need to keep a CO2 bottle connected to them just for storage.
 
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beervoid

beervoid

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Actually, force carbonating is what you are doing to those kegs. The reason the pressure drops is because CO2 is migrating to the beer thus increasing carbonation. If beer is already properly carbonated and the kegs are in good working condition (i.e. no leaks) then you don't need to keep a CO2 bottle connected to them just for storage.
That is the thing, im cold crashing and carbonating the kegs so i'm curious how long this proces will last and if there is any better way to go about it.
 

Vale71

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How longs this lasts depends on how much you have to top up and how cold the beer is stored. Colder beer absorbs CO2 more slowly than warm. Since you do have one CO2 bottle at the storage freezer one not build a manifold so that you can keep as many kegs as you might have at one time connected? That way you just set the target pressure and wait a few days before disconnecting, if there is any pressure drop rettach bottle and wait a few more days and so on and so forth...
 

william_shakes_beer

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I have more full kegs than space in my keezer, so I store the full kegs at room temperature (concrete basement, cool year round) under pressure but uncarbed until I kick a keg and place a fresh one "on deck" to carb. I usually allow a month at serving pressure to carb, but I'm in no hurry. I have a 2 stage regulator and *could* burst carb if I became impatient. Just don't want to add to all those " My keg is over carbed" threads.
 

bleme

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If it is going to be at least 2 weeks before a tap is available, I would add 125 grams priming sugar to the keg and leave it at room temp.

If less, I would build a gas manifold for your carbing fridge.
 
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beervoid

beervoid

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I do naturally carbonate my beers but they are mostly loaded with hops so im not to keen on keeping them warm. Besides im in a warm climate where its 30c + most of the time.

If the beer is done carbonating they should hold their own pressure?
How can one check this? When the pressure is not dropping anymore below desired carbonation level and pressure associated with it from a carbonation chart?
 
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day_trippr

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If the your gas system doesn't have any check valves (not shut off valves but "backflow preventer" valves) you can use the low pressure gauge on the regulator to test the keg head space pressure - after closing the cylinder valve, popping the keg PRV, and letting everything sit for awhile.

Alternatively (and likely more practical - who doesn't have check valves somewhere in their gas systems?) you can attach a pressure gauge to a keg gas connector and snap it on the keg gas post. My spunding valve has a teed-off gauge which is handy for checking keg pressures...

spunding_valve_01.jpg


(That was just for the pic - it's an empty keg ;))

Cheers!
 
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beervoid

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If the your gas system doesn't have any check valves (not shut off valves but "backflow preventer" valves) you can use the low pressure gauge on the regulator to test the keg head space pressure - after closing the cylinder valve, popping the keg PRV, and letting everything sit for awhile.

Alternatively (and likely more practical - who doesn't have check valves somewhere in their gas systems?) you can attach a pressure gauge to a keg gas connector and snap it on the keg gas post. My spunding valve has a teed-off gauge which is handy for checking keg pressures...

View attachment 602369

(That was just for the pic - it's an empty keg ;))

Cheers!
I got a spunding valve but I was curious when do you know the keg can hold its own pressure?
Ive been filling it for 4 days straight to 25psi and it will drop below 10psi within half a day or so, I keep refilling it for now.
 

day_trippr

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Oh, well, one has to have verified the keg is actually gas-tight before filling. Or surely right after. Otherwise the gas man gets paid ;)

There's no chart that would help predict when a quasi burst carb regimen will achieve a carbonation goal, but I carbonate my cold kegs at 12 psi - half that 20 or 25 psi setting you're using - and they take a solid two weeks plus a few days to reach equilibrium at 2.5 volumes.

I don't know if carbonation absorption is a linear function but if we assume it is your four days is roughly halfway to equilibrium which could explain why the head space pressure isn't where you want it...

Cheers!
 

Vale71

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I got a spunding valve but I was curious when do you know the keg can hold its own pressure?
Ive been filling it for 4 days straight to 25psi and it will drop below 10psi within half a day or so, I keep refilling it for now.
The keg can "hold" pressure if it's sealed properly. The pressure will stop dropping once you've achieved the targeted carbonation level, you'll know that's the case when pressure does not drop for at least 24h after the gas line has been disconnected.
 

Unicorn_Platypus

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I have more full kegs than space in my keezer, so I store the full kegs at room temperature (concrete basement, cool year round) under pressure but uncarbed until I kick a keg and place a fresh one "on deck" to carb. I usually allow a month at serving pressure to carb, but I'm in no hurry. I have a 2 stage regulator and *could* burst carb if I became impatient. Just don't want to add to all those " My keg is over carbed" threads.
What PSI to you typically pressurize them at before storing? I recently kegged a beer that I'm cellaring at 58 degrees on oak cubes. Will leave it for at least 3 months.

I pressurized the lid at 40 PSI and its now disconnected from CO2. Will this keg be noticeably carbonated at all if left for a few months disconnected to a CO2 tank?

I usually burst carb and want to avoid overcarbonating when I eventually stick it in my keezer.

Probably best for me to just do the set it and forget it in this case and avoid the risk of overcarbonation. Agree?
 

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Once the 40psi in the tiny headspace is distributed throughout the beer, it would be minimally carbonated. I doubt you'd notice it.
I sometimes cellar uncarbonated beer in the keg. I have pinlocks and there is .6 gal of headspace when there is 5 gal in the keg. I also pressurize the headspace to 40psi and, when the keg is tapped, there is more carbonation than you might expect. Not fully carbed, by any means, but it doesn’t take long at serving pressure to bring the beer up to the desired level.
 

Imhoppy

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After filling the keg, I purge the headspace with CO2. Pressureze keg, close CO2 valve, vent, and repeat several times to remove the unwanted air. Then chill it to 42F until ready to carbonate.

My 2-tap kegerator can hold 3 kegs. When one keg is empty, I then "set-and-forget" carbonate the keg at 12 psi for 2 weeks. So I always have one serving, one carbonating, and one chilling at all times.
 

day_trippr

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What we need is @doug293cz to do the math for us :D
Could some of that carbonation originate from lingering fermentation while cellaring?

Cheers!
 

TheMadKing

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The keg can "hold" pressure if it's sealed properly. The pressure will stop dropping once you've achieved the targeted carbonation level, you'll know that's the case when pressure does not drop for at least 24h after the gas line has been disconnected.
This

I've got the following situation.

I've got a fridge to cold crash and store my beers before I move them to my kegerator where I can connect them to constant co2 pressure.

I've got co2 available at the "cold crash fridge" but I can only keep 1 keg connected at the time.
What i'm doing now is every morning and evening I top it up to about 20psi. This usually drops to about 15-12 psi by the time I check again.

This seems to make sure the kegs keep sealed but it is kind of tedious so im looking for possible solutions and suggestions to perhaps do this another way.
Force carbonating is not an option as I got all loose hops in the kegs.

How long do I need to keep topping up?
Will my beer not be over carbonated at some point?

Cheers!
The pressure in your keg will always equilibrate between the carbonation level in the beer and the temperature - The warmer the temperature the easier time you'll have keeping CO2 in the headspace . Since you are cooling and attempting to keep pressure at the same time, I would just get a manifold and hook all of your kegs up to the pressure for your desired carbonation level (which is dependent on temperature)

For example: If you keep your keg at a temp of 2C hooked up to gas and set your regulator for 5PSI, your beer will carbonate to 2.02 volumes of CO2 over about 2 weeks, and then AFTER that point the headspace in your keg will stay at 5PSI without needing gas hooked up to it. If you want to reduce that time, you can leave your keg hooked up to gas at 30PSI for ~24 hours and it will be sufficiently carbonated for the keg to maintain pressure on its own.

Basically you will either need to keep doing what you're doing OR leave gas hooked up continuously until it has absorbed enough CO2 to carbonate and maintain a few PSI and keep the kegs sealed
 
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beervoid

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This



The pressure in your keg will always equilibrate between the carbonation level in the beer and the temperature - The warmer the temperature the easier time you'll have keeping CO2 in the headspace . Since you are cooling and attempting to keep pressure at the same time, I would just get a manifold and hook all of your kegs up to the pressure for your desired carbonation level (which is dependent on temperature)

For example: If you keep your keg at a temp of 2C hooked up to gas and set your regulator for 5PSI, your beer will carbonate to 2.02 volumes of CO2 over about 2 weeks, and then AFTER that point the headspace in your keg will stay at 5PSI without needing gas hooked up to it. If you want to reduce that time, you can leave your keg hooked up to gas at 30PSI for ~24 hours and it will be sufficiently carbonated for the keg to maintain pressure on its own.

Basically you will either need to keep doing what you're doing OR leave gas hooked up continuously until it has absorbed enough CO2 to carbonate and maintain a few PSI and keep the kegs sealed
If I understand you correctly. If I hook up a keg that is at diacetyl test temp or 72f and pressurize it with 30psi, disconnect and crash it. It should go down to at least 2psi and maintain pressure?
 

TheMadKing

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If I understand you correctly. If I hook up a keg that is at diacetyl test temp or 72f and pressurize it with 30psi, disconnect and crash it. It should go down to at least 2psi and maintain pressure?
Edit using the keg carbonation calculator posted by day_trippr

No not necessarily - that is only a true statement if you leave it hooked up to CO2 for long enough for the beer to carbonate at that temperature. 30 PSI at 72F = 2.5 volumes of CO2, but how long it will take to equilibrate at that temperature is just a guess. I would guess based on experience that 24 hours should be sufficient at that pressure, but I don't know.

After you cool it, the pressure in the head space will drop depending on your temperature. Assuming you reach 2.5 volumes CO2 dissolved in your beer and you cool it to 35F, your headspace will level off at 10 PSI (according to the carbonation chart)
 
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grampamark

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What we need is @doug293cz to do the math for us :D
Could some of that carbonation originate from lingering fermentation while cellaring?

Cheers!
I’m sure there could be some “residual” carbonation taking place. I usually use the cold storage room for cellaring/lagering in the winter when temps in that room never exceed 50°F. Most ale yeasts would be inactive at those temps; lagers would be another story.
 

eric19312

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A carbonated keg is going to stay sealed better. Can you leave the beer in the cold storage fridge hooked up to gas for 24 hours? If so I'd hook the keg up to 30 PSI for 24 hours and then take it off the gas. You will be most of the way to serving pressure and the keg will (should) stay sealed for months. If you don't want to get a splitter you are probably safe enough doing first keg on day 1 and then repeating process on second keg on day 2.
 

day_trippr

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I’m sure there could be some “residual” carbonation taking place. I usually use the cold storage room for cellaring/lagering in the winter when temps in that room never exceed 50°F. Most ale yeasts would be inactive at those temps; lagers would be another story.
Not sure "inactive" at 50°F is a safe bet for most ale strains, "greatly slowed" might be better, with all that entails...

Cheers!
 
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