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Carbonation via spunding

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_HH_

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Hi gang,

I have finally made the change from bottling to kegging, and want to use a spunding valve to carbonate my beer.

My set up is quite different from my friends’ who brew. I am fermenting in a corny, and am using a fermentasuarus floating dip tube so I can serve from the same vessel after cold crashing.

Having bottled and had a sneaky suspicion my bottling technique was letting some O2 get involved in my beer, I’m using the above method of fermenting and serving from the same keg to ensure there is zero oxygen exposure. There is also no need to transfer, and not using bottled CO2 is also cheaper.

My question is this: as my spunding valve stupidly only goes up to 15psi, how can I ensure proper volumes of CO2 are in my finished beer?

What I am planning to do (whilst waiting for a new gauge to arrive!), is to remove the spunding valve once there are 5pts of gravity left in my beer, and allow the pressure to build in the keg to whatever the yeast want to take it to. I will then cold crash for a week, before bringing my IPA up to a serving temperature of 45’F.

At 45’F, as long as the pressure in the keg at that point is 15psi (which I can adjust down to with my spunding valve), am I correct in thinking this would equate to 2.5volumes of CO2? That is what the charts tell me.

Can anyone see a problem with doing this? Is there a better way to do this whilst I wait for my 30psi gauge to arrive?

Thanks for your help!
Henry
 
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It will definitely work, you just have to be patient as dropping down to 15psi will not instantly release excess CO2 from beer. Depending on how much the beer is overcarbed it might take more than one week to adjust to the proper level.
 
Ah that’s fantastic - thanks for your advice! I’ve just taken the spunding valve off now with 7pts to go (est FG 1.012, valve removed at 1.019) so we’ll see how it goes.
 
Do you know whether there’s any benefit to doing it the way I have described above, compared to just setting the regulator at 15psi at the beginning? If I did just set it to 15psi would it mean there were fewer units of CO2 in the beer once it was chilled to serving temperatures and the pressure in the keg reduced due to the fall in temperature?
I can’t quite get my head around what happens to the units of CO2 when it cools!
 
Burst_Cover_GIF_Action_20180610205250.gif keg on right is primary ,left is transfer..i set psi 20
 
View attachment 601247 keg on right is primary ,left is transfer..i set psi 20

Nice set up! Thanks for the tip on setting to 20psi, I’ve got mine set to 15psi currently. It’s currently conditioning in the keg for a week, then I’ll chill to serving temperatures. I’ll let you know what it’s like once I’ve had a try.
 
Inline carb,after transfer ,keg at 39 temp,carb a 20psi.twenty min on the line done..it is just another method
IMG_20180506_101149.jpg
 
I set spunding valves higher, depending on cellar temp, that way when kegs are crashed to serving temp they are at or just above target PSI.
 
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This is 50liter keg,it is in the fisrt phase,which is why the gas line is the blow off to a water bucket. It will say on for about the first 12 then the spunding will go on at 20 psi...the keg only get 10-11 gallon out of the 13..if it is full to the top it will clog the ball locks and spunding
IMG_20180520_181400.jpg
 
I will leave the primary keg sit ,not moving at all.I will let it sit on the spund 1 -2 weeks as i am not in a hurry ..my think is it has 20 psi on it. ..on transfer day .I will hook up pinic (pluto) tap .It will pull up trub and yeast and beer ..It is the first time i will taste my beer...then i will purge the clean starsan corny 5 keg .I will purge the 50l keg and hook up gas co2 to 5psi....to do the transfer....the corny keg should not have any psi or the transfer will stop..I will be watching the transfer line close for the trub yeast to be picked up...I will then put on a pinic tap and havest every thing in a clean jar..I want to reuse the yeast ..IMG_20181124_132831.jpg.On brewday i will take jar out of frige ,when it is time to pitch yeast i will dump out the top part of beer and trub...I will dump the yeast into the keg first,then pump the cool wort on top to help with oxgen..It works in my brew house...The spundy is the thread ,but it is how i use it ....I am not a 'Beer Troll"....stay strong and brew on
 
I set spunding valves higher, depending on cellar temp, that way when kegs are crashed to serving temp they are at or just above target PSI.

Hey Dland! I was interested to read your post, as this is just what I was hoping to find out from my original question. Could you let me know your process for spunding? If you could let me know temperatures and timing of when you add the valve, and how much PSI you end up with at serving that would be super useful!
Thanks :)
 
Hey Dland! I was interested to read your post, as this is just what I was hoping to find out from my original question. Could you let me know your process for spunding? If you could let me know temperatures and timing of when you add the valve, and how much PSI you end up with at serving that would be super useful!
Thanks :)

If you use a carbonation chart, it is pretty easy to figure target PSI based on the temperature of room keg is in. For instance, if you are shooting for 2.5 vols CO2 and your fermentation room is 65F, you would set valve at around 30 PSI, when keg is cooled to 34F, it will be at around 10PSI and around 2.5 volumes C02.

If you undershoot PSI, you can make up the difference with forced carbonation of course.

I ferment in conicals, I'll rack to kegs and put spund valve on when within .006-.008 of target finish gravity, or when fermentation slows but still is steady. If your fermenting a cool lager, you can spund and D rest at same time.

My cellar is usually in the 60s in the summer, and gets down as low as mid 40s in winter. During the winter I often use heated fermwraps and an Inkbirds to move keg temps up for D rest at 64F, and otherwise run lagers in the 53-54 range, ales in the 60s. I keep my 12 keg coffin freezer at 33F, which crashes yeast well, and my favorite serving temp for most beers.
 
I spund all my German styles and use a Tilt to help me gauge when the fermentation progress is appropriate for transfer. It doesn't really matter that much to me if my beer has too little or too much extract when transferred since I'll just set the CO2 pressure on my tank to the proper carbonation pressure after the spunding has completed.
 
Thanks for your detailed response Dland, it’s really helpful for someone new to spunding such as me to see how other more experienced brewers do it.

It’s also good to hear from you Martin, that RDWHAH still applies with spunding, and if it’s a bit over or under-carbed it’s an easy fix.

Just spunding my second brew today! As my 30psi gauge still hasn’t arrived I’m going to keep the spunding valve set to 15psi all the way through and see how this affects things. At least then I’ll have my benchmark!
Once my 30psi gauge comes in I’ll make proper use of the carbonation charts as per your helpful advice Dland.
Thanks guys!
 

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