Korny Keg Size

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Tractorboy

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Having now made a couple of beers, I have invested in a Korny keg (19l) setup and through some careful negotiation I have convinced the wife of the need for a new fridge so that I can use the old one to make a kegerator (which will be this weekend's project).
When I got the CO2 system, I got one with a dual regulator so that I can expand to a second keg. This will easily fit in the fridge alongside my current keg.
Now I have a couple of beers under my belt, I plan to experiment a little, so my plan is to make smaller batches of beer. Would there be any problem with using another 19l keg for smaller batches of beer. I appreciate that I will have to use a bit more CO2 for carbonation and dispense pressure, but would there be any other downsides?
I have noticed from looking online that the smaller kegs seem to be the same price as the large ones, and there also seems to be a lack of reasonably priced reconditioned kegs. So my plan is to buy a second large keg and use it for the smaller batches, with the flexibility to make larger batches when I want. Does this sound reasonable?
 

Drunkula

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Absolutely reasonable. The co2 downside is about it.

For example force carbing and serving half a keg takes 81% of the gas you'd use doing the same for a full keg, quarter of a keg 71% - and that doesn't include if you wanted to purge the headspace. Mad innit.

You could purge the keg with co2 from something fermenting if it were all ready to go so you wouldn't have to purge.
 
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Petrolhead

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Slightly off topic but you could also use the corny as a fermenter or more likely secondary fermenter and save a little on CO2 by fermenting at serving pressure. Easiest is with a spunding valve.
 

Tractorboy

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Absolutely reasonable. The co2 downside is about it.

For example force carbing and serving half a keg takes 81% of the gas you'd use doing the same for a full keg, quarter of a keg 71% - and that doesn't include if you wanted to purge the headspace. Mad innit.

You could purge the keg with co2 from something fermenting if it were all ready to go so you wouldn't have to purge.
Thank you.
I had assumed that the force carbing would be proportional to the amount of beer in the keg, so I guess other factors come into play. I had expected more gas to be used to purge the headspace.
Large keg it is then!
 

xozzx

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You want to be sure all air is purged as you will have a lot of head space. The best way to do this is fill the keg to the brim with starsan then transfer it out (preferrably into another clean keg but a plastic fermenter would work). Next bleed the CO2 pressure from the keg and then do a closed transfer in through the beer out connector. This will guarantee no air in the keg. I started doing this a few brews ago and it works great and probably saves a fair amount of CO2 as I used to purge the keg a lot of times before using it.
 

Petrolhead

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That's a great tip xozzx and I will definitely take up your suggestion. Currently I do the usual squirt and purge a number of times and I am never confident that I have reduced the oxygen to a nominal amount or that this is an economical use of CO2.
 

James

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I have several large cornies and one small one.
I wish it were the other way around - I have taken to bottling a portion and kegging the rest, though I don't have a keezer and the little keg is easier to fit in a normal fridge (I do have brew fridge I can set to dispense temp if I'm not fermenting).
I always feel that the character of the beer, particularly the aroma, changes as the corny gets emptier, though it might just be the new beer novelty wearing off my palate.
Also - the bottles often taste remarkable different but that's more understandable.
I may try the fill with starsan trick on the small keg and then fill it from the larger one. Hmmm....
 

Drunkula

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Somebody should invent this : it's like a ball in two halves slightly weighted on the bottom with a pinhole in the top. You unscrew it, put sugar and yeast in it and put it in a keg and leave a post open and it pushes out the air with its blanket of co2.

Then when you fill the keg if floats on top and the pinhole is at the top and it's fine.

At this point are you buying it or not? Let me know in the comments below!

Ok - let's do the mathems:

1 vol of co2 = 1.96 grams so times 19 = 37.24g (seems like a lot for a load of nothing, don't it, Jean?)
Amount of sucrose to produce 1 vol = 3.81111g, so to make that much co2:
141.9g (that's seems so much!)
Cost at 65p a kilo = 141.9/1000 * 65 = 9.2p

Ok - what about a pub cylinder at £18.99 for 6.35kg?

Cost = 37.24 / 6350 * 1899 = 11.1p

Hmmmm. Well the ball is a saving of 2p per batch, and produces the right amount of co2 under ideal conditions in only a few days. I was thinking of selling them for £9.99. So after 500 kegs it's paid for itself!

Ok. Time to work on the bicarb and vinegar version for those who want results fast.
 

Tractorboy

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You want to be sure all air is purged as you will have a lot of head space. The best way to do this is fill the keg to the brim with starsan then transfer it out (preferrably into another clean keg but a plastic fermenter would work). Next bleed the CO2 pressure from the keg and then do a closed transfer in through the beer out connector. This will guarantee no air in the keg. I started doing this a few brews ago and it works great and probably saves a fair amount of CO2 as I used to purge the keg a lot of times before using it.
OK, so I understand what you are saying apart from the part about doing a closed transfer in through the beer out connector.
I'm thinking that the idea is to get the beer from the fermenter to the keg without it making contact with air. How would this be achieved when transferring from a 23l plastic fermentation bucket. I'm guessing that normal siphoning isn't an option?
Additionally, how would I know when the keg was full via a close transfer? My understanding is that I have to fill the keg to just below the short pipe coming from the CO2 connector.
Apologies if these are stupid questions.
 

xozzx

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How would this be achieved when transferring from a 23l plastic fermentation bucket. I'm guessing that normal siphoning isn't an option?
It may be a bit trickier with a plastic bucket, I use a SS brewbucket and use a very small amount of pressure from my CO2 bottle to push the beer out, however it may work so worth giving it a try. Does your bucket have a bottling tap? Are you using an autosiphon?

To do the closed transfer you want to connect your fermentor to the beer out post. You can cut a short piece of 3/8" hard tubing, connect this to the black (beer) disconnect and attach the disconnect to the beer out post. Connect some rubber tubing to your tap or autosiphon and slide it over the 3/8" hard tubing which is now connected to the keg (I attach a jubilee clip to ensure it doesnt come off). Make sure the pressure bleed off on the keg lid is pulled up (twist it so it stays open) and you can now just start the transfer. The extra resistance as the beer flows through the ball lock will slow the transfer down, this is why I use a small amount of pressure to push the beer out (basically I open the regulator until I can just hear the gas passing through, the gauge doesnt even move. This also means my fermentor is being filled with CO2 instead of air coming in). I found the below pics of my method (not the best pics but is should give an idea). I also use a MD Bouncer filter in line.
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Additionally, how would I know when the keg was full via a close transfer? My understanding is that I have to fill the keg to just below the short pipe coming from the CO2 connector.
I removed these short pipes and cut them to about 5mm long so I can get a bit more beer in each keg. There is no need for them to be full length.
As there is normally a bit of foam created you will start to get some foam coming out the bleed valve in the lid when the keg is full. If you think you might have overfilled it just put some CO2 pressure on the gas in and push some of the beer back out the line. As I cold crash every beer I can see what level it is at as it fills from the condensation forming on the outside. I also lift it up occasionally to get an indication of how full it is.

Hope this helps. The SS buckets are a really good investment if you are looking to upgrade your FV
 

Tractorboy

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It may be a bit trickier with a plastic bucket, I use a SS brewbucket and use a very small amount of pressure from my CO2 bottle to push the beer out, however it may work so worth giving it a try. Does your bucket have a bottling tap? Are you using an autosiphon?
Thank you for the very thorough response. I’ll give this a go next time I transfer a brew.
My plastic FV has a good seal, so I might be able to apply a little pressure via the airlock hole in the lid.
 
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