How long to keep keg in fridge before serving?

[st0neski]

I filled my first keg over a month ago, and it has been on co2 for the same amount of time at 12psi. But it has been sitting at room temp this whole time. How long should I let it sit int he fridge before serving it?

 

[944play]

It will take a week or two for the CO2 to come to equilibrium.
http://www.kegerators.com/carbonation-table.php
https://www.homebrewtalk.com/f35/keg-force-carbing-methods-illustrated-73328/

 

[st0neski]

So even though it has been sitting at room temp/serving pressure for a month, it will still need a week to equalize at the cooler temps?

 

[Yooper]

So even though it has been sitting at room temp/serving pressure for a month, it will still need a week to equalize at the cooler temps?

Yes. Because at room temperature, you'd need about 30 psi to carb it up. If it's at 12 psi, that's the serving pressure/carbonation temperature for 40 degrees not for 70 degrees.

See this chart for specific details:
http://ebrew.com/primarynews/ct_carbonation_chart.htm

With 12 psi at room temperature, the beer isn't the least bit carbed.

 

[IrregularPulse]

As the keg cools, the beer will absorb the co2 more readily. In the future, just keg the beer when it's ready, then put it in the fridge on gas for 2 weeks and start serving.
To get 2 volumes at room temp (assuming 65°) you would need 18.3 psi. The 12psi at 65° you have now get's you 1.6 volumes. So when the keg drops temperature, the beer will absorb more co2 to make up the difference of the current 1.6 volumes and the 2.5 you're shooting for at cooler temps with 12psi.
Confused?

 

[st0neski]

Great, thanks for the explanation guys.

irregularpulse, nope, not confused, your explanation was perfect.

 

[st0neski]

irregularpulse. I didnt keg when the beer wasnt ready, just kegged before the keezer was ready

 

[AnOldUR]

Confused?

If so, check out this. Click and print. Handy reference.

 

[JMass]

Pressure is proportional to temperature, so as you lower the temperature, the pressure will go down. See http://www.kegerators.com/carbonation-table.php. To get 2.4 volumes at 65 degrees F., you need 27 psi. I assume that your room temp is above 65 degrees so you would need more pressure than that at room temp.

It hasn't really been at serving pressure for a month, it has been below. You need to go by volumes, not pressure as pressure changes as temperature changes.

 

[dwolf]

I have had good success after secondary fermentation is done, racking in a keg and purging the oxygen out with some CO2. Then cool to the desired and know temperature for 48hours. Next I put the CO2 on the serving side and set the pressure at the recommend value for the CO2 volume I want. I've found it is drinkable after 48 hours. I've been doing this for only 6 months and haven't noticed a major difference between the 48 hours and 3 weeks later. I did notice on some brew the head seems to have tighter retention after being under pressure for a week.