Keg Pressure

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msppilot

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I just kegged my first home brew on Saturday morning. I set the pressure at 30 p.s.i. and left it until today, Monday. Question one, Is this enough time to fully carbonate it? Second question I backed the pressure off tonight to about 9 to 10 p.s.i. and when I serve it, i am getting a lot of foam. How long will it take for this to go down. Should I bleed the keg a bit, or will it settle down on its own? I am having people over on Saturday and how to serve it then.
 
It will settle on it's own as CO2 is absorbed into the beer.I recommend set the seal with 30-35psi vent twice, then set to 10-12psi and leave it for 2 weeks and your good to go. Burst carbing almost always leads to over carbed
 
I force carbonate at about 30psi after I refrigerate the keg. I give it a good shaking several times a day while listening for the gas moving out of the tank (you can hear it kind of hiss). Then I serve at about 8 psi. I let the high pressure down first. It takes about 2 days to do this and while slow carbonating over a week or so may be better for a thick head, I do get a reasonable carbonation in a short time. I notice that over the next couple of weeks the keg the head characteristics get more creamy.
 
You should be fine. I usually allow a week for carbonating in a keg with the first day or two at ~30 psi. Do you know how many vols of co2 you're wanting? Based on that and your serving temperature you can set the carbonation pressure. It will continue to carbonate/de carbonate to reach your carbonation pressure once you adjust it down. If you get a lot of foam later when you serve you can bleed it off. I don't think there's an advantage to bleeding it now if you're not serving it.

Ideally you'll set the keg pressure based on the desired vols co2 for the beer style you're serving. Then adjust the line length for the pressure drop to achieve ~1/2 psi at the spout.
 
Not sure how many vols of CO2 I need. I brewed an American lite Ale for a party we are having. This is my first attempt at kegging, so it's all new to me.
 
Not sure how many vols of CO2 I need. I brewed an American lite Ale for a party we are having. This is my first attempt at kegging, so it's all new to me.

I'd carb to around 2.7-2.8 volumes for a truly light ale. And make sure to have plenty of 3/16" ID beer line ready to tame it.

You can refer to this chart to set up your carbonation pressure versus the beer temperature.

When you figure out what serving temperature you're going with, make sure to reset the CO2 pressure per the chart to maintain the same volumes of CO2...

Cheers!
 
ok next question is, how to i measure this? I can put a thermometer in the kegerator, but how do I measure the P.S.I in the keg?
 
msppilot said:
ok next question is, how to i measure this? I can put a thermometer in the kegerator, but how do I measure the P.S.I in the keg?

you set your regulator to that psi...it will keep that much in there as long as its connected
 
You're probably getting foam because your serving pressure is lower than the pressure that corresponds to the carbonation level in the keg. Let's say your beer is at 38°, which at your serving pressure of 9 psi corresponds to ~2.3 vol of carbonation. It sounds like you left it at 30 psi for ~50-60 hours, which would result in a pretty high carbonation level, much higher than 2.3 vol. By only applying 9 psi, the gas wants to come out of solution as it sits, and forms pockets of gas in the lines, which create foamy pours.

You need to decide what level of carbonation you want, and then consult the chart linked above to determine the serving pressure. If pockets of gas are still forming in the lines at this pressure, it means you overcarbed the beer, and will need to disconnect the gas and repeatedly vent the pressure for a day or two to bring the carbonation back down.

If there are no gas pockets forming in the line at this new pressure, but you're still getting foamy pours, the next thing to look at is the serving line length. The higher the pressure and/or temperature, the longer your lines need to be to slow the beer down and prevent it from becoming a foamy mess.

FWIW when I'm in a rush and use the carbonation method you tried, I only leave it on the higher pressure for ~36-40 hours, and then reduce to serving pressure.

ok next question is, how to i measure this? I can put a thermometer in the kegerator, but how do I measure the P.S.I in the keg?

Typically you don't. You set the regulator to the pressure that corresponds to the beer temperature and desired carbonation level.
 
Silly question, did you purge the keg before dialing it down from 30 psi to 9 psi? That may cause some issues if you didn't.
 
You can download the manual for that unit from here. On page 8 a close-up of the CO2 regulator is shown along with simple instructions on how to use it...

Cheers!
 
Sorry Juan, didn't mean to make things confusing. From what I am understanding is there are two pressures to look for. The CO2 tank pressure and the pressure of the keg itself. I can adjust the CO2 tank pressure but it doesn't look like I have the second regulator for my unit. I got it used so who know what may of happened to it. What I did notice was the temperature of the refrigerator was turn to the lowest setting. I tuned the temp down this morning so hopefully that will help as well.
 
Did you look at the manual I linked? That unit came with a single regulator.

There's only one pressure to "look for" regarding setting the pressure to the keg, and you set it by turning the big shiny regulator knob and watching the low pressure gauge, which if your regulator matches the one in the manual for your kegerator, is the one at 12 o'clock. As long as the other gauge reads a few hundred psi with the tank valve wide open you're good to go.

Honest, this really isn't that complicated...

Cheers!
 
I do see what you are referring too. My regulator is slightly different then the one pictured. I do not have the gauge that reads the tank pressure, just the output pressure. No big deal on that one. I think my issue was with the temperature, that gauge was turned to the warmest position. I turned it down but that made it too cold. Now that I understand the pressure part, I just have to get my temperature dialed in. Thanks again for the advice.
 
Oh course, I am still over carbonated. I did purge the keg and hopefully the beer will absorb the excess carbonation over the next few days.
 
My regulator has a little valve that I can turn off the gas without using the valve on the tank. I let out most of the gas if the beer is overcarbonated, and then use the little valve to add more serving pressure as I need it.
 
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