Spunding Valves

I just built a couple of these. Since I ferment in cornies I figure I'll just put them on when I'm not getting any more blowoff and set it to the PSI I want depending on the beer and the temp. When it's done fermenting I'll pull the spunding valve off and cold crash it, then transfer to a serving keg.

Anybody see a problem with this plan?

Nope, pretty much what I do every single time I brew. Should work perfectly. What psi are you going to ferment at and at what temperature?

WortMonger said:

Nope, pretty much what I do every single time I brew. Should work perfectly. What psi are you going to ferment at and at what temperature?

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I have a helles bock in the cellar at 50 degrees with one on it that I'm going to set at 17psi if there is enough sugar left to get it that high. It was pretty much done already by the time I found all the parts I needed so not sure there is enough sugar left to carb it all the way. At the very least I won't have to use as much CO2 to carb it.

smellysell said:

I have a helles bock in the cellar at 50 degrees with one on it that I'm going to set at 17psi if there is enough sugar left to get it that high. It was pretty much done already by the time I found all the parts I needed so not sure there is enough sugar left to carb it all the way. At the very least I won't have to use as much CO2 to carb it.

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The helles was up to 20 psi when I checked it tonight when I got home. Adjusted the valve a little and it's sitting nicely at 17 now.

I understand the principal of a spunding valve.
But I am not exactly sure about the exact procedure.
Does the valve have settings on it to set the pressure or?
You set the PSI on the releif valve then wait till the gauge reads that # and then it's carbed to the right volumes?

You should read THIS EPIC THREAD

ScubaSteve said:

You should read THIS EPIC THREAD

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Yea that's epic alright, I was looking for a little more basic explanation
googled up this for anyone else who needs the basics
http://***********/stories/projects-and-equipment/article/indices/20-build-it-yourself/400-build-your-own-spunding-valve-to-carbonate-in-the-keg

dzlater said:

Yea that's epic alright, I was looking for a little more basic explanation
googled up this for anyone else who needs the basics
http://***********/stories/projects-and-equipment/article/indices/20-build-it-yourself/400-build-your-own-spunding-valve-to-carbonate-in-the-keg

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Thanks for that link. I have started to read the epic thread two or three times but did not make it through. The magazine article though is wonderfully brief and to the point and I could finish it even with my short attention span.

Yea, I have started doing some keg priming and maybe want to try krausening, or transferring to the keg before fermentation is done to carbonate. And just wanted a simple explanation of how to use the spunding valves.
That thread was way more then I needed to know.

Sorry, yeah... the thread starts off with a lot of different stuff that is all over the place. the wiki article is much more to the point. My thread has been on for many years now and is way too big to just pick up and read. It is good though for everyone wanting to take different approaches to the technique. Basic works though! there is no need to make it any more difficult than just holding pressure, unless you are doing experimentation or wanting a more in-depth knowledge into what has been done. that way you don't have to make the same mistakes we made.

If I understand correctly, the pressure helps twofold. One, the yeast ferment more cleanly at pressure. Two, you won't have to carbonate at the end of fermentation if you do a fast ferm test so you know to expected final gravity.

In terms of the original question, I believe the spund valve is not calibrated. You use a separate pressure gauge to get it where you want it. This requires being around the fermenter while it's coming up to pressure I guess.

1). Pressure does help to keep ester production minimized by slowing yeast growth. Fusel alcohols are also minimized. Diacetyl at first rises fastly, but then towards the end of fermentation cleans up quickly.

2). Carbonation is part of the process. The thread talks about all of our experiments, and different from the other stuff you read some of us are going the whole primary at wanted carbonation volumes. Some use a step pressure. Lots of ways to skin a cat. The benefits in fermenting at your wanted volumes is: First having time to dial in the pressure via temperature and the gauge, and second being 100% carbonated at the end of primary fermentation.

You do have to be around your pressure gauge and mess with it for this technique, unless you buy several valves and have them set to release at a certain pressure. The beer I have going right now, I pitched Friday night. Sunday it started showing pressure early in the morning, and by that evening it was over-pressured. No problem, since I was watching it, but the outcome would have been way over-pressured if I hadn't caught it before bed. I set the valve to release until I hit the 30 psi I wanted and went to be. It has been there ever since. I used to take readings and pressure up at the end. Now, I don't worry about that. I only worry about not catching my valve in time to over-pressure. Under pressure at the beginning is advisable!!!

Hmmm, so I'm thinking I wouldn't want to do this for a saison, hefe, etc. then?

Nope, I think this is best reserved for everything else. You can always just ferment as normal and transfer into a spunded vessel a couple of gravity points from finish though and get your carbonation. After the growth phase of your yeast, pressure really doesn't effect those things.

WortMonger said:

Nope, I think this is best reserved for everything else. You can always just ferment as normal and transfer into a spunded vessel a couple of gravity points from finish though and get your carbonation. After the growth phase of your yeast, pressure really doesn't effect those things.

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Yeah, I guess that's true. If I just wait until the end to put it on, it should still work fine for those styles. The helles is in the ferm freezer for a D-rest right now, then I'll cold crash it and transfer it to a lagering keg, already carbed!

This may sound stupid, but what method are you using to get gravity readings, especially with the closed pressurized system? I think this is a simple and slick way of fermenting and kegging and want to have all my ducks in a row, so sorry if I sound like a tool.

I am thinking about using a corney and blow-off for primary and then a corney with spunding valve as a secondary/serving. Might even want to try a full pressurized fermentation after I get the bugs worked out, for styles that need to have lower esters/cleaner profiles.

I am new to kegging, so with the secondary do you leave at fermenting temps, and use the pressure level required to get proper carbonation at serving temps? So if I needed 13 psi at 40*F I leave the relief there even though I am conditioning at 68*F prior to cold crashing?

I am trying to have 2 corneys as primaries, and 4 as secondaries/serving, with a minimal amount of transfers. Also plan on doing a kegerator, CO2 to push for serving and transfers, etc.

sasky7777 said:

This may sound stupid, but what method are you using to get gravity readings, especially with the closed pressurized system?

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There is lots of information in my thread, but the way I do it now is with a picnic tap. Just like if you were serving the beer. Actually, now that I am going 100% start to finish in the primary, I don't have anything but the spunding valve hooked up. I trust when I am done by process, but recommend to anyone starting out to always take samples.

sasky7777 said:

I am thinking about using a corney and blow-off for primary and then a corney with spunding valve as a secondary/serving. Might even want to try a full pressurized fermentation after I get the bugs worked out, for styles that need to have lower esters/cleaner profiles.

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You can transfer and then spund a few points from finishing if you want to, but I prefer to do it all in my primary. You can do it as mentioned with a blow-off and then seal the keg up and spund for finish and carbonation.

sasky7777 said:

I am new to kegging, so with the secondary do you leave at fermenting temps, and use the pressure level required to get proper carbonation at serving temps? So if I needed 13 psi at 40*F I leave the relief there even though I am conditioning at 68*F prior to cold crashing?

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If you move to secondary and want carbonation, you treat the same as if you were priming. Instead of adding sugar, you are relying on the remaining sugar, so you want to finish at fermentation temps or higher like for a diacetyl rest. Since growth phase has occurred already, you will get no off-flavors from a warmer fermentation. You will want to set your spunding valve for carbonation volumes wanted at whatever temperature you are at. If you cold crash or anything after that, simply un-tap and let what pressure is in drop on its own due to temperature. So, just say you were at 30 psi for 2.5 volumes @ 68*F once you spunded. Once you are ready to crash cool you fall to 13 psi for 2.5 volumes @ 40*F (numbers may not be accurate, but you see what I am saying). It is easier to dial in carbonation at higher temps. The beer wants to give up gas easier, and so if you are over-pressured after you are finished fermenting/carbonating (which I recommend for this very reason) it is easy to release that excess pressure fast. Not so easy at 40*F, due to the beer wanting to keep the CO2 in solution.

WortMonger said:

You will want to set your spunding valve for carbonation volumes wanted at whatever temperature you are at. If you cold crash or anything after that, simply un-tap and let what pressure is in drop on its own due to temperature. So, just say you were at 30 psi for 2.5 volumes @ 68*F once you spunded. Once you are ready to crash cool you fall to 13 psi for 2.5 volumes @ 40*F (numbers may not be accurate, but you see what I am saying). It is easier to dial in carbonation at higher temps. The beer wants to give up gas easier, and so if you are over-pressured after you are finished fermenting/carbonating (which I recommend for this very reason) it is easy to release that excess pressure fast. Not so easy at 40*F, due to the beer wanting to keep the CO2 in solution.

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So if the beer is at 2.5 volumes at 68*F, I can take off the spunding valve, and cold crash it, and since the CO2 is more soluble at colder temperatures, the psi will fall on its own, but the volumes stay the same. So I don't need to work backwards on the temp, just look at CO2 volumes, as long as that doesn't push me over the release psi level of my spunding valve at 68*.

Pressure and temperature are directly relative of each other. Since you have pressurized and equalized the pressure in the beer and the head space at the higher temperatures (say 68*F and 2.5 volumes at 30 psi), as the temperature drops so does the pressure. the only thing that stays the same is the carbonation volume of 2.5. Heat it back up and the pressure will rise, but the volumes of CO2 will remain the same. This is if you are sealed by the way. Directly relative to each other.