Water as a spunding valve?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

Djangotet

Well-Known Member
Joined
Nov 15, 2022
Messages
82
Reaction score
12
Location
California
Hey I am definitely not smart enough to figure this out but I’m wondering if I wanted to ferment under pressure and I put the gas out hose into a gallon of liquid, how much psi would that generate? Is it possible to generate anywhere near 5 psi by altering the water? Would water pressure do enough to give the benefits of pressure fermentation without carbonation? After you could just force carb. I keep hearing that spunding valves are not accurate so I’d almost rather the beer not carbonate to an unpredictable level.
 
Last edited:

TheMadKing

Western Yankee Southerner and Brew Science Nerd
HBT Supporter
Joined
Jun 17, 2015
Messages
4,130
Reaction score
2,448
Location
Gainesville
The volume is irrelevant. It doesn't matter whether you put the hose into a gallon of water or the ocean, the amount of pressure needed to push the bubble out of the end of the tube is determined by the head pressure of water over the tube end (so the depth of the tube)
 
Last edited:
OP
OP
Djangotet

Djangotet

Well-Known Member
Joined
Nov 15, 2022
Messages
82
Reaction score
12
Location
California
The volume is irrelevant. It doesn't matter whether you put the hose into a gallon of water or the ocean, the amount of pressure needed to push the bubble out of the end of the tube is determined by the diameter of the tube and the head pressure of water over the tube end (so the depth of the tube)
Interesting, my goal is to retain about 5 psi of pressure in my keg. I will be using the fermentation gasses from my first keg to purge my second one. I don’t wanna lose all the aroma. Probably a spunding valve is my best option?
 

doug293cz

BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
HBT Supporter
Joined
May 14, 2014
Messages
13,833
Reaction score
10,946
Location
Renton
The volume is irrelevant. It doesn't matter whether you put the hose into a gallon of water or the ocean, the amount of pressure needed to push the bubble out of the end of the tube is determined by the diameter of the tube and the head pressure of water over the tube end (so the depth of the tube)
Yes, and just for reference, you would need the end of the hose about 11 feet deep in the water to get 5 psi.

Brew on :mug:
 
OP
OP
Djangotet

Djangotet

Well-Known Member
Joined
Nov 15, 2022
Messages
82
Reaction score
12
Location
California
Yes, and just for reference, you would need the end of the hose about 11 feet deep in the water to get 5 psi.

Brew on :mug:
Is the very little amount of pressure applied when submerged in a gallon of water enough to reap the benefits or should I just get a spunding valve with a 10psi limit?
 

doug293cz

BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
HBT Supporter
Joined
May 14, 2014
Messages
13,833
Reaction score
10,946
Location
Renton
Is the very little amount of pressure applied when submerged in a gallon of water enough to reap the benefits or should I just get a spunding valve with a 10psi limit?
If you want more than 1 psi, get a spunding valve. You could get 1 psi by connecting to the liquid out post of a keg full of water.

Brew on :mug:
 
OP
OP
Djangotet

Djangotet

Well-Known Member
Joined
Nov 15, 2022
Messages
82
Reaction score
12
Location
California
If you want more than 1 psi, get a spunding valve. You could get 1 psi by connecting to the liquid out post of a keg full of water.

Brew on :mug:
I was thinking of doing that, filling the second keg with starsan and pushing the water out with fermentation gas. Then finishing the job with my co2 tank. But I’d need 3 kegs to do it, or fermentation bucket. Hmm… might be worth a try.
 

brewbama

Well-Known Member
Joined
Sep 20, 2013
Messages
3,681
Reaction score
2,333
I ferment under ~2 psi until I get to 1-2% of extract remaining, then closed transfer to the keg that was full of iodophors and purged with fermentation CO2, attach a spunding valve, raise the fermentation chamber temp by 5°F to secondary under 30 psi (~2 bar). It’s my effort to allow the yeast to consume inadvertent O2 introduced during xfer and clean up any by-product from fermentation and simultaneously carbonate the beer. I then cold condition under CO2 pressure to keep positive pressure on the inside of the keg as the contents contract.

VLB’s Annemüller documents the process in Managing Fermentation and Maturation of Beer although I think it’s been around longer than that. But he did study the process and document the results as a viable solution. These are the ‘Cliffs Notes’: Fermenting lagers in 21 days
 

D-Max

Member
Joined
Apr 19, 2017
Messages
23
Reaction score
7
Location
Nelson
The volume is irrelevant. It doesn't matter whether you put the hose into a gallon of water or the ocean, the amount of pressure needed to push the bubble out of the end of the tube is determined by the head pressure of water over the tube end (so the depth of the tube)
From my diving experience every 30 feet of water above you equals approximately 15 PSI of pressure.
So for 10 PSI you would need a depth of approximately 20 feet.
 
Top