transition from forced carb to serve
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Yes. You should purge and then raise it to 6 psi again.
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Serving pressure is the pressure required to maintain the volumes of CO2 fit for the style. 6 psi is not enough. For most beer, it's in the 10-12 pound area. Then you use line length to get a good pour.
Even if you purge it, the pressure in the head space will soon return to a pressure well above your serving pressure as CO2 comes out of solution. Your mistake was leaving it at 30 pounds for two days.
Even if you purge it, the pressure in the head space will soon return to a pressure well above your serving pressure as CO2 comes out of solution. Your mistake was leaving it at 30 pounds for two days.
Yep, 6 PSI is far too low. Unless you're serving below freezing, I guess.
If you can't get good pours when the beer is in the 10-15 PSI range, then your line lengths are all wrong. Too foamy means too short of lines. No head and too slow means too long of lines.
First determine how many volumes of CO2 your style of beer needs. You didn't say what style it is, so here's a chart. http://www.tastybrew.com/calculators/priming.html
Then look for that number of volumes at your known serving temperature on this page. http://www.kegerators.com/carbonation-table.php
For example, I'll if you were force carbing an American Pale (2.26-2.78 vol), you might go middle of the road at 2.5 vol. If your serving temperature is 41F, then your beer needs to be at just shy of 12.8 PSI or so.
Why did you force carb for 2 days at 30 PSI? Unless you have a Wheat or other highly carbed beer, you're almost certainly overcarbed at this point. Next time, try force carbing at 3x the serving pressure for 24 hours. In the case of this American Pale at 41F, you'd carb at 38 or 39 PSI for 24 hours.
For now, figure out the appropriate serving pressure and reduce your regulator to that pressure. Every few hours, burp the keg using the pressure relief valve until you hear the regulator groan. You can speed it up by shaking between burps if you really must. It's going to take a little time to get it back out of the overcarbed range, unless you were carbing exceptionally warm.
If you can't get good pours when the beer is in the 10-15 PSI range, then your line lengths are all wrong. Too foamy means too short of lines. No head and too slow means too long of lines.
First determine how many volumes of CO2 your style of beer needs. You didn't say what style it is, so here's a chart. http://www.tastybrew.com/calculators/priming.html
Then look for that number of volumes at your known serving temperature on this page. http://www.kegerators.com/carbonation-table.php
For example, I'll if you were force carbing an American Pale (2.26-2.78 vol), you might go middle of the road at 2.5 vol. If your serving temperature is 41F, then your beer needs to be at just shy of 12.8 PSI or so.
Why did you force carb for 2 days at 30 PSI? Unless you have a Wheat or other highly carbed beer, you're almost certainly overcarbed at this point. Next time, try force carbing at 3x the serving pressure for 24 hours. In the case of this American Pale at 41F, you'd carb at 38 or 39 PSI for 24 hours.
For now, figure out the appropriate serving pressure and reduce your regulator to that pressure. Every few hours, burp the keg using the pressure relief valve until you hear the regulator groan. You can speed it up by shaking between burps if you really must. It's going to take a little time to get it back out of the overcarbed range, unless you were carbing exceptionally warm.
You're getting foam for one of four reasons. Overcarbonation is ruled out because of the 6 PSI, so we're down to two.
1- The faucets are warmer than the beer. When the cold beer hits the warm faucets, the faucets get colder and the beer gets warmer. This causes the beer to be able to hold less dissolved CO2, so some falls out of suspension, causing turbulent flow and a chain reaction. In really bad situations, you can hear sputtering. You can determine if it's this one by touching the faucet or using an IR thermometer, then pouring a few pints.
2- The lines are kept warmer than the beer in the keg. Same as above, CO2 falls out of solution because of the temperature increase. This pushes some beer back into the keg and leaves CO2 pockets in the lines. This one is visible in all transparent and semi-transparent lines when you open the lid.
3- You have a major imbalance between keg pressure and line flow restriction. Very possible in this case. You either need longer or thicker lines. At only 5', you'd need something in the range of 5/16" ID line for around 12 PSI.
Use this formula to get a rough idea for how long your lines should be:
4- Damnit, I forgot already.
If you have Bev-Seal lines, then they need to be much longer.
Hope this helps.
1- The faucets are warmer than the beer. When the cold beer hits the warm faucets, the faucets get colder and the beer gets warmer. This causes the beer to be able to hold less dissolved CO2, so some falls out of suspension, causing turbulent flow and a chain reaction. In really bad situations, you can hear sputtering. You can determine if it's this one by touching the faucet or using an IR thermometer, then pouring a few pints.
2- The lines are kept warmer than the beer in the keg. Same as above, CO2 falls out of solution because of the temperature increase. This pushes some beer back into the keg and leaves CO2 pockets in the lines. This one is visible in all transparent and semi-transparent lines when you open the lid.
3- You have a major imbalance between keg pressure and line flow restriction. Very possible in this case. You either need longer or thicker lines. At only 5', you'd need something in the range of 5/16" ID line for around 12 PSI.
Use this formula to get a rough idea for how long your lines should be:
Brewer's Friend said:
4- Damnit, I forgot already.
If you have Bev-Seal lines, then they need to be much longer.
Hope this helps.
It's very common to experience 1 and 2 in a keezer because they don't have fans to recirculate the air. Stratification sets in. At the bottom, it's 10F colder than the top.
The solution is a recirculation fan of sorts. If you're in a refrigerator, I assume it has one already.
The solution is a recirculation fan of sorts. If you're in a refrigerator, I assume it has one already.
Cool. 
I fill two glasses when a tap is fully warm. Drink the second one. First one settles out to about 1/3 cup... dump it om top of the full one once its down half way.
I fill two glasses when a tap is fully warm. Drink the second one. First one settles out to about 1/3 cup... dump it om top of the full one once its down half way.
