Spunding PSI

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Brews and Blues

Brews and Blues

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Background on this brew: I am fermenting and serving a black IPA in one keg. I used a blow off tube until day 7, which is when i added the spunding valve. My plan is to spund until fermentation is complete and i hook up to co2 and throw in the kegerator. Today is day 9 and the brew has been temp controlled at 63F - yeast US-05. My question is, what PSI do i want my spunding valve at. The one i have is adjustable. It has slowly crept up to about 15 PSI currently. Not sure where that should be at. This is my first time using it and i have no idea what my goal PSI should be.
 
I'm guessing around 25-30 PSI at your current temps. Once it's totally done fermenting and you move it to the kegerator, the psi is gonna drop as it cools down. Once it's cold crashed the keg psi should be close to what your regulator is already set at for serving.
 
I'm currently doing my first single keg ferm & serve. A steam beer ferming at 55-60 so I'm targeting 20 psi until it finishes.

But I don't have a spunding valve yet. I just put a press gauge on the gas post and bleed the PRV to 10 psi every so often and let it build again. Once it stops "rebuilding" I'll know it's done fermenting.
 
Thanks everyone!
So if my psi is low, the only effect will be that i will need additional efforts from the co2 to get my beer carbonated correct?
 
That's right, you just have to partially force carb up to desired levels if you undershoot spunding pressure. (or I suppose add sugar, but would avoid this as is an oxidation risk at this point).
 
Why wouldn’t you pressure ferment from day 1 if you have a spunding valve and a fermenter that holds pressure?
 
Jim R said:
Why wouldn’t you pressure ferment from day 1 if you have a spunding valve and a fermenter that holds pressure?
Click to expand...

If you mean ferment under high pressure from day 1, I wouldn't do that because it supresses (slows) yeast actvity. I "spund" from the beginning, but at only about 2 PSI gauge.
 
So far I've set my spunding valves to 14-15psi from the start and let things ride. Solid results for those batches.
Next two batches, I plan to set the spunding valves at a lower limit and see what that gives me. One is another stout and the other is a best bitter. Probably somewhere in the 5-10psi limit (haven't decided just yet, could be different for the two recipes).
IMO, not having to change out a blow-off assembly for the spunding valve is a GOOD thing. One less time you're opening things up to risks.
 
Dr_Jeff said:
I've had a lively fermentation several times and had yeast blowing out of the vents on the spunding valve, what a mess.
Click to expand...
What spunding valve was that? How much headspace did you have in the fermenter?

I've put almost 7 gallons into a 7-3/4 gallon fermenter without any issue at all with the blowtie I was using. Going to the SSBrewTech setup for the conicals. Conical capacity is 14 gallons and I don't expect to put more than about 10-11 gallons into them (for 9 gallon to keg/can batches).
 
I use this calculator.
https://drhansbrewery.com/beercarbonationcalculator/
I start with about 10/15 psi for clean non expressive ferments and leave it open or just a couple of psi if I want the yeast to do it's thing, then turn it up as the krausen falls. I aim to have enough pressure in the fermenter for my serving vols at the end of ferment or a day or two before. Pressures can be quite high with kveik ie 35 psi at 30 celsius for 2.3 vols. I also purge the keg and fill it to that pressure so that when I do closed transfer and the fermenter pressure has dropped during the cold crash the keg pressure excess nearly runs the whole transfer.
@VikeMan I accidentally sealed the fermenter from day one ( due to a non return ball lock connector I fitted on my spunding valve - I hadn't thought it thru) on a wheat beer it was fermenting like crazy on day 5 when I checked it and was at 35 psi.
Also the yeast seems to be going fairly well in this video



But the pressure does affect how the yeast works but perhaps not that much in terms of speed, I've not done a side by side test though.
 
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No doubt, there are many ways to spund. Some here seem to be fermenting at pressure and will of course end up with a "spund carbonated" product, if all goes well.

What has worked out for me best is to rack from primary to kegs when there is still a little fermentation to go,( & do D rest at same time if a lager). This is admittedly with the luxury of conical fermentor dump & rack valves, plenty of kegs, etc.

I'm sure there are a lot of ways to get good results for experienced brewers who know their gear. You'll know when your have got spunding right with your rig when you get good results, and it hardly takes any extra effort.
 
Golddiggie said:
What spunding valve was that? How much headspace did you have in the fermenter?

I've put almost 7 gallons into a 7-3/4 gallon fermenter without any issue at all with the blowtie I was using. Going to the SSBrewTech setup for the conicals. Conical capacity is 14 gallons and I don't expect to put more than about 10-11 gallons into them (for 9 gallon to keg/can batches).
Click to expand...

15.5 gallon fermenter, Belgian Quad - WLP-530 yeast, big pitch (yeast cake from a wit) likely 11-11. 5 gallons in 64=65 degrees or so if I remember correctly, it's been a while. (4 years ago, maybe)
 
DuncB said:
I start with about 10/15 psi for clean non expressive ferments and leave it open or just a couple of psi if I want the yeast to do it's thing, then turn it up as the krausen falls. I aim to have enough pressure in the fermenter for my serving vols at the end of ferment or a day or two before. Pressures can be quite high with kveik ie 35 psi at 30 celsius for 2.3 vols. I also purge the keg and fill it to that pressure so that when I do closed transfer and the fermenter pressure has dropped during the cold crash the keg pressure excess nearly runs the whole transfer.
Click to expand...

+1. This is almost exactly what I do and it works perfect every time.
 
Dr_Jeff said:
15.5 gallon fermenter, Belgian Quad - WLP-530 yeast, big pitch (yeast cake from a wit) likely 11-11. 5 gallons in 64=65 degrees or so if I remember correctly, it's been a while. (4 years ago, maybe)
Click to expand...
Still don't see what spunding valve you used. But judging by the time frame, it's not one that I've used. So far I've used both Blowtie models and will be using the SSBrewTech TC connected model. I'll probably give one of the Blowtie setups to my nephew if he's going to brew with friends out in the Chitcago area (he's going there since his fiancee is going to grad school out there). I'll keep the other in case I do something in one of my kegmenters (instead of the conicals).
 
Any spunding valve is better than that all metal one they used to sell ( I had to modify mine seen on the right in this picture). Required the skills of a safe cracker to set that and even then was unreliable.
IMG_20210318_101554.jpg
 
Vikeman, does that low pressure(2 psig) suppress the krausen enough for a 10.5 gal batch in a 13.2 gal conical? I'm getting the Fermzilla on Tues and use 2565 as a house yeast and use a blowoff every time.
Also wondering if using the capture CO2 method (pushing 5 gal of sanitizer into another keg) is enough pressure to suppress the krausen.
 
hottpeper13 said:
Vikeman, does that low pressure(2 psig) suppress the krausen enough for a 10.5 gal batch in a 13.2 gal conical?
Click to expand...

It doesn't, I suspect, do much at all to supress krausen. If I'm worried about my combination of gravity, yeast strain, fermentation temp, batch size, and headspace size causing a blowoff, I use a blowoff for a couple days, then switch to the valve. But that's maybe 5% of my batches.

hottpeper13 said:
Also wondering if using the capture CO2 method (pushing 5 gal of sanitizer into another keg) is enough pressure to suppress the krausen.
Click to expand...

I don't use the sanitizer method. But I think it would depend on how much pressure is needed to push it in your system.
 
Jim R said:
Why wouldn’t you pressure ferment from day 1 if you have a spunding valve and a fermenter that holds pressure?
Click to expand...
The OP was fermenting in a keg. That is why. Minimal head space. Maybe 1/2 a gal. There will be blow off...or blow out :O

I'm attempting to ferment in the serving keg as well. I got my full 5 gal of wort plus one pint in there. The first couple of days it's gonna have some blow off that i would not want in my valve and gauge. When the bubbling slows down is when I'll cap it and let it pressurize as it finishes.
 
odie said:
The OP was fermenting in a keg. That is why. Minimal head space. Maybe 1/2 a gal. There will be blow off...or blow out :O

I'm attempting to ferment in the serving keg as well. I got my full 5 gal of wort plus one pint in there. The first couple of days it's gonna have some blow off that i would not want in my valve and gauge. When the bubbling slows down is when I'll cap it and let it pressurize as it finishes.
Click to expand...
I've never understood the desire to ferment in serving keg. You'll always be down a good amount of volume due to the blowoff, or headspace needed, plus the yeast sediment in the bottom. For a long time I did ferment in sanke kegs (or kegmenters I guess they call them these days). Pressure transfer to serving kegs, with those being full.
 
Golddiggie said:
I've never understood the desire to ferment in serving keg.
Click to expand...
I never knew it was a thing.

There are many way to brew and ferment...everyone has their own reasons...and their own objectives.

Depending on one's own system and methods, they may or may not have the same issues of volume, headspace, blowoff and yeast that you experienced.
 
odie said:
I never knew it was a thing.

There are many way to brew and ferment...everyone has their own reasons...and their own objectives.

Depending on one's own system and methods, they may or may not have the same issues of volume, headspace, blowoff and yeast that you experienced.
Click to expand...
True... I've found that fermenting under pressure I can get 7 (or a little more) gallons in the tall 1/4 bbl kegmenter and NOT need a blowoff setup. Previously, if I didn't leave a gallon of head space, I'd need to have the blowoff setup in place right after pitching yeast.

I need to find new homes for most of my kegmenters.
 
Golddiggie said:
I've never understood the desire to ferment in serving keg. You'll always be down a good amount of volume due to the blowoff, or headspace needed, plus the yeast sediment in the bottom. For a long time I did ferment in sanke kegs (or kegmenters I guess they call them these days). Pressure transfer to serving kegs, with those being full.
Click to expand...

I just did a full 5 gallon batch and didn't have one drop come through my blow off tube. There was plenty of headspace at least with the US-05 and i had good fermentation.
The reason why i want to ferment and serve in the same keg is so i don't have to transfer. Less cleaning and less work.
As far as the sediment, i am using a floating dip tube so it shouldn't be an issue until the keg blows.
 
Closed system transfers eliminates any potential issues from that. Moving off the yeast cake also eliminates needing to install floating dip tubes. You're also limited in what size batch you can ferment in each vessel. I have kegmenters sized from about 3-1/2 gallons up to 15-1/2 gallons. We did a 12 gallon (into carbonating/serving kegs) batch in the 15-1/2 gallon kegmenter last.
With my new conicals (getting their first batches Sunday and then sometime next week) I'll have even more options and be able to fine tune things easier. Dry hopping is going to be easier and O2 free. I'll be carbonating in those before moving some to serve on tap and the rest will go directly into cans.

Did you use a 5 gallon keg for that 5 gallon batch? Or did you use one of the 6 gallon Torpedo kegs to get 5 gallons out??
 
I've got 2 beers going right now in kegs. 5+ gal of wort in each 5 gal corny (they hold 5.5). Nothing came out the blow off except bubble and a little foam. the jar the tube was in did not gain any volume. Both have slows down and the blow off tube was replaced by the gas post.

My old methods the wort is screened so there is only 1/2 of trub or yeast at the end of fermentation. I expect my first pint to be the yeast harvest followed by hopefully clear beer. If not, then a floating dip tube will be my next modification.
 
Golddiggie said:
Closed system transfers eliminates any potential issues from that. Moving off the yeast cake also eliminates needing to install floating dip tubes. You're also limited in what size batch you can ferment in each vessel. I have kegmenters sized from about 3-1/2 gallons up to 15-1/2 gallons. We did a 12 gallon (into carbonating/serving kegs) batch in the 15-1/2 gallon kegmenter last.
With my new conicals (getting their first batches Sunday and then sometime next week) I'll have even more options and be able to fine tune things easier. Dry hopping is going to be easier and O2 free. I'll be carbonating in those before moving some to serve on tap and the rest will go directly into cans.

Did you use a 5 gallon keg for that 5 gallon batch? Or did you use one of the 6 gallon Torpedo kegs to get 5 gallons out??
Click to expand...

Standard 5 gal corny keg. They hold a bit more than that really and it was the perfect amount of space for fermentation actually. That being said, i don't aerate. I just give it a good mix. I did temp control a little low - around 63F, so maybe those things kept the fermentation from being out of control. And maybe a different yeast and aeration would give me different results.
If I like the end result of this brew, I will be using this method every time. It basically leaves all of the work on brew day, which is nice for me because spare time always eludes me LOL.
 
Brews and Blues said:
Standard 5 gal corny keg. They hold a bit more than that really and it was the perfect amount of space for fermentation actually. That being said, i don't aerate. I just give it a good mix. I did temp control a little low - around 63F, so maybe those things kept the fermentation from being out of control. And maybe a different yeast and aeration would give me different results.
If I like the end result of this brew, I will be using this method every time. It basically leaves all of the work on brew day, which is nice for me because spare time always eludes me LOL.
Click to expand...
Shifting to a conical (15psi working pressure rated) allows me to cold crash the entire batch (I'll be able to do this with my normal batch sizes since the fermenter can hold up to 14 gallons) and then carbonate it in a few days (they say 24-48 hours, I'll probably go 48-72 hours). I can then pressure/closed transfer part to serving keg to go into the keezer (my normal keg size is 3 gallons) and then can/bottle the rest directly. The fermenters are on locking wheels, so they'll roll from the brewing area into the fermenting area. The glycol chiller means I can either do precise fermentation temperature control (more a concern in the summer) as well as cold crash as desired/needed.

I'll also be able to dump the yeast out the bottom once fermentation is done and they've all settled down (probably post cold crash). I can dry hop as well, dumping the hop matter out (if needed/desired) before carbonating the batch. Or, rather, finish carbonating the batch. Since I'll also be fermenting under pressure. I'm planning to put dark brews (stouts and porters) at a higher ferment pressure than IPAs and other pale ales. Of course, that also depends on what I want from the yeast.

I'll fine tune my methods over the next few batches with the new fermenters.
 
30.5 litres in a 34 litre fermentasaurus, no blowouts or escapes started under minimal pressure and then turned it up.
I find the krausen is well controllable with the pressure and spuning appropriately. That said did clean my Duotight spunding valve out the other week and there was a bit of gunk in there.
 
@Golddiggie
Agreed I use similar pathway, my fermenters higher pressure rated so I aim for carbonation level correct at end of ferment. That's about 35 psi at 30 celsius if a kveik ferment.
Flushing the kegs out and then purge with CO2 for a good while after really gets rid of any oxygen prior to transfer.
 
I’m new to spunding. Once my beer gets to about 1.022 or so (6-10 points left), I can just set it to 20-30 psi? That’s not going to prematurely stop fermentation, right?

And using a tilt, will the gravity readings be worthless once I start spunding?
 
A related question about the tilt hydrometer. One of the beers I am currently fermenting is an English porter that I brewed Sunday. I pitched a starter of wlp002 around 5pm and it took off later that night. According to my tilt it went from 1.050 to 1.025 in about 24 hours and down to 1.016 by 36 hours. That’s when I put on the spunding valve set to 20psi.

I have a little fear that the 1.016 reading isn’t right, really just because it’s so soon after pitching. I think this yeast just does that sometimes? I’ve read that high krausen can cause inaccurate tilt readings. My graph is steadily downhill, but bounces around a bit. Bounces where it might drop 4 points suddenly then back up 3 and down 2. Not more than that.

Anyway, I guess my point is to ask if the Krausen makes the tilt reading totally unreliable or just off a few points and therefore safe to assume I’m sub 1.020 and safe to sound at a high psi.
 
murphyslaw said:
I’m new to spunding. Once my beer gets to about 1.022 or so (6-10 points left), I can just set it to 20-30 psi? That’s not going to prematurely stop fermentation, right?

And using a tilt, will the gravity readings be worthless once I start spunding?
Click to expand...
That's pretty much what I do for ales, just more 15-20 psi for my own preference. I'd double check the Tilt reading.
 
murphyslaw said:
A related question about the tilt hydrometer. One of the beers I am currently fermenting is an English porter that I brewed Sunday. I pitched a starter of wlp002 around 5pm and it took off later that night. According to my tilt it went from 1.050 to 1.025 in about 24 hours and down to 1.016 by 36 hours. That’s when I put on the spunding valve set to 20psi.

I have a little fear that the 1.016 reading isn’t right, really just because it’s so soon after pitching. I think this yeast just does that sometimes? I’ve read that high krausen can cause inaccurate tilt readings. My graph is steadily downhill, but bounces around a bit. Bounces where it might drop 4 points suddenly then back up 3 and down 2. Not more than that.

Anyway, I guess my point is to ask if the Krausen makes the tilt reading totally unreliable or just off a few points and therefore safe to assume I’m sub 1.020 and safe to sound at a high psi.
Click to expand...
On the occasions I miss the window for fixing the spunding valve, I just add some sugar to the FV before fitting the spunding 🤫
 
murphyslaw said:
I’m new to spunding. Once my beer gets to about 1.022 or so (6-10 points left), I can just set it to 20-30 psi? That’s not going to prematurely stop fermentation, right?

And using a tilt, will the gravity readings be worthless once I start spunding?
Click to expand...
that's pretty much my current method. ferment ales in the keg with a blow off tube. after a couple 3 days or so, I will remove the blow off tube, install a spunding valve and let it finish out as the remaining fermentation raises the PSI from zero to around 15-20.

If it's a lager I will spund from the start, but at ale temps.

It will finish carbed but not over carbed. So when I tap it and set my regulator, it should finish carbing quickly.
 

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