Continuous CO2 build up

[BarnBrian]

I've got SMASH that I made about three months ago. It's in a cornie and every time I draw off a beer it's virtually all froth. I keep venting the pressure down to close to zero but it just builds up again. I've got no CO2 connected to it and no sugar was added during legging. The beer tastes good, no off flavours.
Any ideas.

Brian

 

[Steved53]

I've got SMASH that I made about three months ago. It's in a cornie and every time I draw off a beer it's virtually all froth. I keep venting the pressure down to close to zero but it just builds up again. I've got no CO2 connected to it and no sugar was added during legging. The beer tastes good, no off flavours.
Any ideas.

Brian

I've got a few like that, and as they are also cloudy and taste disgusting, I am guessing they have some sort of infection. It is possible that you also have one, just not a horrible tasting one, or as far advanced as mine.

Assuming you took a final gravity reading when you kegged, maybe try and take another one, and see if there has been a substantial lowering of gravity.

 

[peebee]

Hello Brian. Firstly; how over-carbonated did it get? You can vent off excess pressure in the headspace, but the dissolved CO2 takes very much longer and will just replace the CO2 in the headspace after a few hours, especially if the keg is pretty full. You can keep venting off the headspace pressure and you will catch up eventually. In pubs they'll use "soft spiles" to vent the pressure for maybe a day or so. I use aquarium "bubble counters" because it gives me a bit more control (after hours of venting I don't want to drop the pressure below 1-2PSI).

Secondly; I could go along with "Steve53" (previous post) and say "infection". But infected with the most obvious culprit ... the yeast! Yeast is a living organism and doesn't have to work by the Book, and a medium/low attenuator might well slowly adapt to become a high attenuator. I get this all the time with S-33 yeast which has stopped at a FG of 1.020, then after a few weeks or months slowly gets going again. I had one keg in long maturation pressure up to near 100PSI before I noticed.


(EDIT: We discussed my use of bubble counters in an earlier thread: http://www.thehomebrewforum.co.uk/showthread.php?t=72738. I actually fix my bubble counters in the gas supply lines because they are so useful.)

 

[Godsdog]

Hello Brian. Firstly; how over-carbonated did it get? You can vent off excess pressure in the headspace, but the dissolved CO2 takes very much longer and will just replace the CO2 in the headspace after a few hours, especially if the keg is pretty full. You can keep venting off the headspace pressure and you will catch up eventually. In pubs they'll use "soft spiles" to vent the pressure for maybe a day or so. I use aquarium "bubble counters" because it gives me a bit more control (after hours of venting I don't want to drop the pressure below 1-2PSI).

Secondly; I could go along with "Steve53" (previous post) and say "infection". But infected with the most obvious culprit ... the yeast! Yeast is a living organism and doesn't have to work by the Book, and a medium/low attenuator might well slowly adapt to become a high attenuator. I get this all the time with S-33 yeast which has stopped at a FG of 1.020, then after a few weeks or months slowly gets going again. I had one keg in long maturation pressure up to near 100PSI before I noticed.


(EDIT: We discussed my use of bubble counters in an earlier thread: http://www.thehomebrewforum.co.uk/showthread.php?t=72738. I actually fix my bubble counters in the gas supply lines because they are so useful.)

can you explain how you connect and how you use them in a cornie keg system for a no nothing about them bloke:thumb:ta

 

[JapanBrew]

Put your co2 on the out side of the keg (noted this will take screw drivers, spaners and a whole lot of curse words to get the ball lock off) and force 10 psi through it while the vent is open. It might spray so put a towel over it. This will de carb your beer. If the co2 comes back in 24 hours you've got a wild yeast issue.

 

[peebee]

can you explain how you connect and how you use them in a cornie keg system for a no nothing about them bloke:thumb:ta

You mean the bubble counters? Give me a day or so to get together my easier-to-explain "stand-alone" version, but there is an explanation in my document on "Cask" home-brew under "venting" ... https://drive.google.com/open?id=0BwzEv5tRM-5EQUhZbDNPdmV1bWc. Basically the bubble counter is connected via a needle valve (to control the speed of venting) to a tee on the gas line going to the keg.

You won't like what I'm doing now! The photo is the CO2 controls for my "cask" styles for my work-in-progress bar. The bubble counters and needle valves can be clearly seen on the outputs from the low-pressure LPG regulators (the regulators appear to be "upside-down" so any condensation doesn't collect in them):

 

[BarnBrian]

I think posting on the forum has scared it into submission. After venting for down to about 2 psi for about seven days it's now started to behave itself as it should. I think I must have over carbonated in the first place and left it pressured up for too long.

 

[BarnBrian]

Put your co2 on the out side of the keg (noted this will take screw drivers, spaners and a whole lot of curse words to get the ball lock off) and force 10 psi through it while the vent is open. It might spray so put a towel over it. This will de carb your beer. If the co2 comes back in 24 hours you've got a wild yeast issue.

I can't follow your logic on his on.

Brian

 

[JapanBrew]

I can't follow your logic on his on.

Brian

If you ever over carb your beer, you can force co2 through the beer and it will push out the co2. It's weird but it works. The gas lock goes on the "out" post on your keg. Open your vent and apply the gas. It will push out the gas in the beer. Then you can re carb your beer.
But it sounds like it was just over carbonated. Glad it wasn't a wild yeast issue. Those suck.

 

[Godsdog]

If you ever over carb your beer, you can force co2 through the beer and it will push out the co2. It's weird but it works. The gas lock goes on the "out" post on your keg. Open your vent and apply the gas. It will push out the gas in the beer. Then you can re carb your beer.
But it sounds like it was just over carbonated. Glad it wasn't a wild yeast issue. Those suck.

Have to be careful swapping the gas QD onto the beer out post as there is a nominal difference in the diameter size,not much just a few thows but enough to make it a pain to get back off again

 

[Alside101]

just leave the pully thing on the lid open for a day or so or buy 1 of these a d set the psi you want and it will let any pressur out you dont want

https://www.themaltmiller.co.uk/index.php?_a=viewProd&productId=804

 

[peebee]

Have to be careful swapping the gas QD onto the beer out post as there is a nominal difference in the diameter size,not much just a few thows but enough to make it a pain to get back off again

Dead right! If you've got pin-locks (I have) you can't do it anyway, but it is surprisingly easy to put a ball-lock on the wrong post (and have endless fun trying to get it off).

But I think "JapanBrew" neglected to suggest you need to fit the gas line to a "beer out" disconnect. The process sounds interesting, but there does seem to be a lot of messing about and potentially quite a mess to clear up after. And I guess the beer needs a few days to settle after such treatment.

... or buy 1 of these and set the psi you want and it will let any pressure out you dont want
https://www.themaltmiller.co.uk/index.php?_a=viewProd&productId=804

Never cared for these, using a PRV to finely manage pressure seems a bit crude to me. The pressure relief component was intended as emergency pressure relief. The price doesn't include the post either. Still, better than nothing (perhaps?).

(EDIT: This inspired me to lookup prices on low-pressure - beer is low pressure - relief valves. The prices were ... let's say eye-watering).