Carbonating in secondary?

[Wort*hog]

I 'm sure this has been covered and I'm thinking out loud but here goes. In secondary, if you were to use a blow off tube going to a second carboy. The end of the outlet tube was submerged at a depth of 15 inches. The pressure at that depth is a tad over 15 psi. I reason that would maintain 15 psi on the brew in the secondary if the stopper and tubing connections could hold that pressure. I know at serving temp 15 psi is enough to carbonate. Any body have any input?

 

[Drunkensatyr]

I am almost certain that you would blow something. Prolly just enough pressure to raise the blow off out of the water, or out of the top of car boy or the cap. IF that all held, I don't know that I would EVER want to keep a 20lb glass shrapnel grenade around my house.

 

[Wort*hog]

If the pressure of water at 15'' is 15psi then the pressure at the bottom of a full carboy would be around 15 psi and they withstand that every day.

I just filled a carboy. using a tube and racking cane I blew through the tube and sensed the pressure and various depths. harder to blow as you lowered the end of the cane at 15 inches it was not that hard, nothing that would blow the tube off the cane by any means.

 

[Muss]

When you bottle the already carbonated brew you might end up with foam all over the place.

 

[Wort*hog]

When you bottle the already carbonated brew you might end up with foam all over the place.

I keg! a quiet transfer to the keg would give a jump on carbonation.

 

[Alamo_Beer]

since you keg why don't you use a keg as a secondary and try it? you could always blowoff some of the pressure if it was too great...

 

[rfidd]

I 'm sure this has been covered and I'm thinking out loud but here goes. In secondary, if you were to use a blow off tube going to a second carboy. The end of the outlet tube was submerged at a depth of 15 inches. The pressure at that depth is a tad over 15 psi. I reason that would maintain 15 psi on the brew in the secondary if the stopper and tubing connections could hold that pressure. I know at serving temp 15 psi is enough to carbonate. Any body have any input?

Not quite sure your calculation of converting pounds per square inch to inches of water is correct. I think it should be something like 1 psi equals 2.31 feet of water. So theoretically if you could submerge your outlet tube to 34.6 feet would give you 15 psi (15x2.31), then you might get there.

Rick

 

[Wort*hog]

This is the calculator I used;
http://www.mrhall.org/science/waterpressurecalc/waterpressurecalc.htm.

It doesn't seem right. I'll see if I can find another!

 

[Denny's Evil Concoctions]

I would not carbonate in a carboy, that is just plain dangerous.

If you keg and want to carb naturally, rack to a keg 3 days into fermentation and let the beer finish in the keg, you'll be fully carbed.

Use a shortened outlet or add a piece of tubing to the outlet tube bent back up wards so that it's above yeast level. Or alternatively just tap and most of the yeast will come out in the first few pints. Just don't bump the keg afterwords.

 

[rfidd]

This is the calculator I used;
http://www.mrhall.org/science/waterpressurecalc/waterpressurecalc.htm.

It doesn't seem right. I'll see if I can find another!

Yeah, I think another source might be advised. This guy is a first grade teacher? Pretty heady stuff for first graders. Anyway, I am pretty sure he is incorrect.

Rick

 

[JimC]

He is, 15psi is a ~34 feet of salt water or ~35 feet of fresh water.

 

[Wort*hog]

Boy howdy? I entered 38.1 centimeters=15" and got 15???psi then changed to 38.1 mm ( 1 tenth as deep) and got14.???

 

[JimC]

Here is the proper (well, close to proper) equation.

Let P be pressure in psi
Let D be depth in ffw (feet of fresh water)

P = D * 14.7 psi / 33.9 ffw

 

[david_42]

That calculator is hosed. 15" = 15 psi, 15 FEET = 21 psi? I don't think so.

As an ex-submariner: divide feet by 2 for psi. Close enough if you aren't at crush depth (AKA war time operating limit, RLY!)