Natural Carbonation using SS Brewtech Unitanks

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Crusty

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I'm wondering if any of you guys with the SS Brewtech Unitank can explain your natural carb method using the spunding valve.
I know that you close off the tank a couple of points above FG but wondering when you dump the yeast?
To get a decent yeast dump, the beer would need to be chilled before dumping but hows that gunna work if you want to naturally carb the beer.
I know most micro's crash chill then dump the yeast before carbonating with the carb stone. One bloke I spoke to crash chills, dumps yeast, sets his spunding valve to 0.8bar, 12psi then turns on the CO2. Takes at least a couple of hours & then it's carbed. I'd like to have a crack at naturally carbing using the spunding valve. Putting the tank under pressure before a decent yeast dump will have too much suspended yeast floating around won't it? Maybe dump just before closing the tank, naturally carb, cold crash, then dump remaining settled yeast, then transfer carbed beer to keg?
 
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Hi Crusty. I use one of those unitanks. I don't bother with a yeast dump. I leave the beer on the yeast until kegging. With naturally carbing I set the spending valve at approx day 3-4 but usually pretty low pressure, maybe 20kpa. Once I know the gravity is within about 5 points of terminal I close the blow off pipe and remove the spunding valve and let the pressure rise to what ever, it usually gets high enough to activate the PRV, 140 kpa. Once the beer is at terminal I start to chill the fermenter to about 6-7 degrees and the pressure is around 70 kpa. I use cylinder gas to push the beer into the keg and have the spunding valve on the keg to prevent the beer from fobbing to much. Yeast gets cleaned out afterwards or on the odd occasion I will dump a new beer straight onto the cake. With chilling the unitank prior to kegging I don't get a lot of suspended yeast, the longer the chill the more yeast that drops out, but you knew that.
 
Wouldn't the chilled yeast start to clump? Also I think you meant to write CO2 not oxygen.
Pity you haven't got 2 then you could use one as a bright tank.

I did mean CO2, thanks. I'll fix that up now.
The Unitanks do away with the need for a bright tank. I'll be getting more of them but I'm waiting on the glycol unit to be back in stock & that's my next purchase.
 
Hi Crusty. I use one of those unitanks. I don't bother with a yeast dump. I leave the beer on the yeast until kegging. With naturally carbing I set the spending valve at approx day 3-4 but usually pretty low pressure, maybe 20kpa. Once I know the gravity is within about 5 points of terminal I close the blow off pipe and remove the spunding valve and let the pressure rise to what ever, it usually gets high enough to activate the PRV, 140 kpa. Once the beer is at terminal I start to chill the fermenter to about 6-7 degrees and the pressure is around 70 kpa. I use cylinder gas to push the beer into the keg and have the spunding valve on the keg to prevent the beer from fobbing to much. Yeast gets cleaned out afterwards or on the odd occasion I will dump a new beer straight onto the cake. With chilling the unitank prior to kegging I don't get a lot of suspended yeast, the longer the chill the more yeast that drops out, but you knew that.

Thanks razz.
I thought it might of been essential to get the yeast off the beer before carbing & this is why I was so confused as to how it's done with natural carbonation. As above, the commercials chill, drop the yeast then carb via the carbonation stone but still use the spunding valve to determine pressure or carb level. Have you carbed via the stone? I just ordered the sampling coil for mine & the 3" tri-clover CIP ball. Going to run that sucker with a Davey pressure pump I have here, does over 70l/min at about 48m head. If you got a sight glass, what one did you opt for?
My Unitank is a 1/2bbl.
I did read somewhere maybe over at SS Brewtech that it's a good idea to leave the yeast in place during transfer as it takes up the void in the cone. If you dump it, beer will fall into the cone with some of the yeast so doing it that way, recovers more usable wort.
Cheers
 
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I haven’t bothered with the brew tech carb stone, the first time I hooked it up and turned on the gas the head blew off and I threw it in the bin! The coil would be handy but very pricey, I draw off a sample and swirl it around to get the gas out before taking a gravity reading. The CIP fitting I have, very handy piece of kit. But I always take out the Tri clamp fittings and check them before running the sanitizer.
 
I haven’t bothered with the brew tech carb stone, the first time I hooked it up and turned on the gas the head blew off and I threw it in the bin! The coil would be handy but very pricey, I draw off a sample and swirl it around to get the gas out before taking a gravity reading. The CIP fitting I have, very handy piece of kit. But I always take out the Tri clamp fittings and check them before running the sanitizer.

Thanks razz.
I wasn't going to worry about the sampling coil but it's a shitload easier to take samples with it.
I'm waiting for more stock to come in & chasing the SS Brewtech spunding valve next order.
Do you set the racking cane in a horizontal position during ferment or just leave it facing down.
 
Thanks razz.
I wasn't going to worry about the sampling coil but it's a shitload easier to take samples with it.
I'm waiting for more stock to come in & chasing the SS Brewtech spunding valve next order.
Do you set the racking cane in a horizontal position during ferment or just leave it facing down.
I leave the racking cane face up Crusty, just run a little beer to waste before connecting to kegs. I'm thinking about getting the SS adjustable valves bit of a "i want it" rather than "I need it" though. If they are available from GrainNGrape next Fathers Day sale I'll get one.
 
I leave the racking cane face up Crusty, just run a little beer to waste before connecting to kegs. I'm thinking about getting the SS adjustable valves bit of a "i want it" rather than "I need it" though. If they are available from GrainNGrape next Fathers Day sale I'll get one.

Cheers razz.
 
I haven’t bothered with the brew tech carb stone, the first time I hooked it up and turned on the gas the head blew off and I threw it in the bin! The coil would be handy but very pricey, I draw off a sample and swirl it around to get the gas out before taking a gravity reading. The CIP fitting I have, very handy piece of kit.
I use the carb stone after cold crashing, last brew it worked very well but others not so well. I think the pores can get clogged.
Does the sampling coil de-gas the sample? I thought it was just like having afew meters of 4mm serving line, gives some restriction?
I have the full CIP setup but honestly it's just as much effort to set it up as it is to clean by hand. As Razz too all the fittings have to come apart anyway.
 
I use the carb stone after cold crashing, last brew it worked very well but others not so well. I think the pores can get clogged.
Does the sampling coil de-gas the sample? I thought it was just like having afew meters of 4mm serving line, gives some restriction?
I have the full CIP setup but honestly it's just as much effort to set it up as it is to clean by hand. As Razz too all the fittings have to come apart anyway.

If I decide to force carb it, I think I'll get a sight glass & a longer carb stone & inject it through the racking butterfly valve.
The Coil acts like the serving line & restricts the flow so the sample is much easier to test. Under pressure, the tap itself pours basically just foam.
 
Under pressure, the tap itself pours basically just foam.
I have not had this issue what so ever and last batch was a stout, forced carbed in tank and reached 11psi, still pulling samples with minimal foam. 🤷‍♂️
 
I have not had this issue what so ever and last batch was a stout, forced carbed in tank and reached 11psi, still pulling samples with minimal foam. 🤷‍♂️

Good to know but according to SS Brewtech themselves, foaming can be an issue.
Maybe just a marketing stunt so like me, you'll buy something you might not need.

 
I'm wondering if any of you guys with the SS Brewtech Unitank can explain your natural carb method using the spunding valve.
I know that you close off the tank a couple of points above FG but wondering when you dump the yeast?
To get a decent yeast dump, the beer would need to be chilled before dumping but hows that gunna work if you want to naturally carb the beer.
I know most micro's crash chill then dump the yeast before carbonating with the carb stone. One bloke I spoke to crash chills, dumps yeast, sets his spunding valve to 0.8bar, 12psi then turns on the CO2. Takes at least a couple of hours & then it's carbed. I'd like to have a crack at naturally carbing using the spunding valve. Putting the tank under pressure before a decent yeast dump will have too much suspended yeast floating around won't it? Maybe dump just before closing the tank, naturally carb, cold crash, then dump remaining settled yeast, then transfer carbed beer to keg?
I have put this article up a few times, this is the brewer who started the pressure fermenting fad, she explains the way they did it in the brewery just got picked up and went off at a tangent on homebrewtalk and now pressures are being applied to some unusual levels.
http://www.terifahrendorf.com/Closed-Pressurized-Fermenatation.pdfRead the paragraph on Steel Head Brewery.
 
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