carbing a corny keg

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mancer62

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after reading lots of posts I now realise that force carbing my corny would work so much better after i have chilled the beer. Unfortunately i do not have the facility to do this and I would have to force carb at room temp....
I therefore would like to know the best way to do a normal carb of the corny.
Would this take around 7 days? more? less?
Once i put beer in keg and before i connect my gas line do I first purge the keg?
then connect gas line and put co2 in?.... to what pressure?
once my dial shows this pressure do i shut valve off then disconnect or leave valve open?
do i shut valve off at this pressure and keep gas line connected
find it hard to grasp if when i reach my required psi do i leave connected and run gas or shut down disconnect...
 
After a quick Google I came across this carbonation chart which shows the temperature vs PSI to gain your desired co2 volume.

force_carbonation_psi.png

As I am sure the image won't render well, the link is

http://mikebirdgeneau.com/blog/force-carbonation/#

If you follow this chart just leave it connected at the desired result for 7 to 10 days (I'll probably be wrong here) and then crank down to your serving PSI.

Keep gas on throughout
 
Oh and purge the keg a few times, always good practice

Yep, put the gas on, set to the pressure you want, and with the gas still on, pull the ring on the pressure release valve. You'll hear a really loud PSSSHHHTTTT of air and CO2 coming out. It will scare your cat.

Give it a count of 5, then do it again.

Then again.

I normally do about 5 'burps' to make sure all air, and hence O2, is purged from the keg.
 
and if you are new to kegging check for leaks - I have lost more than a few kilos of CO2 force carbing.
 
I am always worried about leaks and never leave the gas on I once purged give a blast upto the desired PSI then shut off the gas and proceed to give further blast of gas and then turn off again. I do probably 3 burst in the first 24 hours to keep it topped up to the PSI I have selected as the gas is absorbed by the beer then I do it once a day thereafter until it is at the desired PSI and so do not run the risk of a bad connection and coming to a empty bottle of gas
 
I am always worried about leaks and never leave the gas on I once purged give a blast upto the desired PSI then shut off the gas and proceed to give further blast of gas and then turn off again. I do probably 3 burst in the first 24 hours to keep it topped up to the PSI I have selected as the gas is absorbed by the beer then I do it once a day thereafter until it is at the desired PSI and so do not run the risk of a bad connection and coming to a empty bottle of gas

Tend to do this also. The keg of stout I have the nitro connected to seems particularly prone to not showing any leaks but then leaking as soon as the gs line into the JG on the disconnect gets slightly knocked.
 
Bit the bullet kegged earlier today this is how i done it hope its ok...lol
1. beer into keg
2. muslin bag with 50g Citra into keg
3. with gas connected couple lbs pressure then purged.
4. increased to 30 PSI then disconnected
5. if this is right how long till i can test beer.
6. I presume when carbed just reduce to serving pressure ie 10psi ish?
7. from today sitting at 30 PSI how long would u say till its a.Fully carbed & B. Ready to drink?
Cheers
 
Bit the bullet kegged earlier today this is how i done it hope its ok...lol
4. increased to 30 PSI then disconnected
Leave the gas connected, it won't carb otherwise. You'd need a permanent 30PSI for about 10 days to achieve roughly 2.5vols; with an assumed ambient temperature of 20C.

The issue you will face is that you can't really serve at 30PSI, unless you use an unusual beer line length and/or diameter. If (as you have said) you "reduce to serving pressure of 10PSI-ish" - you're going to find your beer goes flat pretty quickly. As 10PSI will give you about 1.5vols; which is flat beer.

The worse part of all this is that you're going to be drinking 20C beer which is a nightmare in itself.

I'd look into building a kegerator as it will be something you're going to realistically have to do. If not that, back to bottling.
 
Back before I had a keezer 30psi would result in a sure fire glass of foam. Even now I only pressurise lagers to 20psi or so at 6C and they're gassy enough for the style.

If I were you I'd back off down to 15psi or so and leave it there for a week before trying it.

Carbing beyond the pressure you serve at risks foam. Think about what happens when you take a sealed bottle of fizzy drink, crack the lid to release a bit of pressure then screw it back on. The contents fizz up inside until enough CO2 has been released to get back to equilibrium. It's the same if you try to vent keg pressure then serve - you'll have decarbonating beer running through the lines.
 
… As 10PSI will give you about 1.5vols; which is flat beer. …
Honestly … gheesh!

Did you say that because you're bored and want to kick off a blazing argument?

Most of my beer is primed for 1.3ish volumes and served with 1.1 volumes (2psi). Do you ever hear me whining that my beer has no head or is "flat"? The lager I have on is cooled to 7C and held at 14-15 PSI to retain the 2.5 volumes created by 40g of sugar in 20L at kegging. Is "priming" considered an inferior technique now-a-days? That would be odd given that I'm seeing an increasing number of bottle-conditioned "premium" lagers popping up in supermarkets.

I think I'll partner with @foxbat as he's obviously missing this trick too; bang up the pressure in my kegs to something b***-crunching, and see if I can flog them as foam fire extinguishers for a decent price.
 
ive gone to the expense of a large co2 tank + 2 cornies and taps etc and your telling me if i dont build a kegerator id be better going back to bottles...
so the 30psi i put into my kegs then disconnected wont carbonate them yes?no?
what u recommend i do now then?
 
Did you say that because you're bored and want to kick off a blazing argument?
Absolutely not @peebee; not my style and not why I'm posting here. So please calm down a little as you sound quite excited.

My reference of "flat beer" at 1.5vols actually rings true for many popular styles. To name but a few: Lagers, American pales and IPA's, Wheat beers, Saison, Helles, Kolsch. That should be enough to reiterate my point here. 1.5vols for any of these popular styles is under-carbonated. A popular synonym for this anomaly: flat.

I don't know where you're pulling incorrect correlations between priming and inferiority. Please show me where I said that? We; or certainly myself and the OP; are talking force carbing.

If you read the OP's post, properly this time, you'll see that he is not only focusing on force carbing, but more importantly doing so at room temperature. Thus why we're addressing the potential issues and hurdles surrounding the lack of cooling to aid carbonation at a lower pressure.

Take a look at this chart, you can see that a "middle of the road" 2.3 vols at room temp is >25PSI. A lot of pressure when you consider serving and carbonating should ideally be the same.

https://www.kegerators.com/carbonation-table/

If carbed at 25PSI to achieve ~2.3vols; then reduced to serving pressure of "10PSI-ish" - after a short while the CO2 will come out of solution to maintain the head pressure and cause the beer to become undercarbed from our "middle of the road" figure of 2.3vols.

I'm not arguing here because I simply don't have time, but if you wish to contest anything I've said as incorrect then feel free. But, if we are both indeed talking about force carbing at room temp to achieve correct carbonation for any of the popular styles I mentioned, then it's science and that's all there is to it.

In short: bucket loads of pressure to achieve and maintain the desired vols at room temperature. Simple.
 
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ive gone to the expense of a large co2 tank + 2 cornies and taps etc and your telling me if i dont build a kegerator id be better going back to bottles...
so the 30psi i put into my kegs then disconnected wont carbonate them yes?no?
what u recommend i do now then?
I've been in a similar position as you having recently bought a corney keg and other assorted bits. I opted to use a sodastream gas bottle which runs out pretty quickly. But the one beer I've had in the keg so far I ended up force carbing it, had 30psi running through it for an hour or so with a gentle rock with my foot every 10 minutes or so. Then I dialled down the psi to serving and job done, fizzy beer with a good head.

If you can cool the beer whilst having co2 going into it then it'll get fuzzier quicker. I now have the problem of keeping the keg cool with no room for another fridge, but that's another story
 
ive gone to the expense of a large co2 tank + 2 cornies and taps etc and your telling me if i dont build a kegerator id be better going back to bottles...
so the 30psi i put into my kegs then disconnected wont carbonate them yes?no?
what u recommend i do now then?
1) If you want to carb upwards of 2vols at room temperature then you need a high pressure on your keg. If you want to keep that same calculated volume in solution throughout the life of your keg, then you have to serve at the same pressure you carb. Do do this you need to balance your lines, so you'll need a fair length of beer line to avoid excess foaming. You could easily serve at 30PSI with 2-3m of 3/16" beer line.

2) If you're happy drinking room temperature beer then you won't have to build a kegerator. But, I would hedge my bets that you like cold beer? As you've purchased everything else anyway, investing in a second hand fridge is a mere fraction of the cost vs what you've already spent. My first one was £15.

3) If you put a blast of 30PSI into a keg full un-carbonated - it will simply absorb it over a reasonably short time and you will no longer have 30PSI in your keg. The beer will continue to absorb CO2 until it has reached equilibrium with the headspace. There is no definite time period for this, but 7-10 days is a solid estimate. So, 30PSI at room temperature for 7-10 days would give you around 2.5 vols. Reference the chart I linked in my last post to target estimated vols against the ambient temperature of your kegs. You can choose whatever you like against your beer temperature.

My point about going back to bottling if you're not going to build a kegerator is based on the premise that you want cold beer. If you don't want cold beer, then it's a non issue budathumb..
 
… My reference of "flat beer" at 1.5vols actually rings true for many popular styles. …
My point was don't write garbage when giving advice; and then don't try to justify it with lame excuses. I was referring to my lager so people wouldn't see my comments as a bigoted outpouring and I then went off at a bit of a tangent about "priming"; sorry if you still thought I was referring to you. At least it was me picking on you for your bad prose, there are plenty of other more "excitable" folk out there.

Anyway, @mancer62 doesn't want to hear this: The rest of what @Ghillie writes is sound, as are some of the other comments you (@mancer62) have collected. Let me put it in piccies and summarise it.

CO2 in keg.jpg

You start with the first keg of 20L beer and a headspace of roughly 1L full of CO2 (presuming you purged the headspace). The beer will have roughly 1 volume (20L) of CO2 dissolved in it from fermentation (again, presuming the beer was kept away from air with an airlock or something). It will actually have about 0.85-0.90 volumes dissolved, but 1 volume is close enough. You want beer with 2.5 "volumes" of CO2. That's 2.5x the volume (20L) less the 20L it already contains … (2.5x 20 = 50L, 50-20 = ) … you need to dissolve 30 more litres of CO2. You put 30PSI in the headspace; that's roughly 2 bar or 2 "atmospheres" (1 atmosphere = 14.7 psi), so you've added 2L of CO2, and you need 30. See the problem?

One solution as mentioned above is just leave the gas regulator attached and give the CO2 time to dissolve. The other is shake the keg between top-ups of CO2 (you'll need to do this 15+ times), CO2 will readily dissolve. Another is add about 66g of sugar (at 20C) and let the yeast generate the CO2 but you will have sediment to watch out for.

But 2.5 volumes of CO2 in beer will be very unstable at 20C (will probably instantly turn to foam). And beer at 20C wont be very nice. Even the "cask conditioned" stuff ("Real Ale") isn't good at that temperature. Which is why everyone here is building "kegerators" or making other cooling arrangements (I use "shelf coolers" too). CO2 dissolves into beer better at lower temperatures too (so less psi).
 
My point was don't write garbage when giving advice; and then don't try to justify it with lame excuses.
On your bike @peebee. Excuses, bad prose, writing garbage? 1.5vols is a useless carbonation target for virtually all beers. Unless; for example; you were making a porter, stout or some sort of brown ale. But even then, as per BJCP guidlelines (and what would they know?!), 1.5vols even for those lower carbed styles is still under-carbonated! I'm not making this up, that's just how it is. I didn't make the rules!

Take your angry little man syndrome and get back in your box. You're the one who got excited, banging the drum about batch priming kegs. You saw so much red mist you weren't even on the same topic as everyone else:laugh8:

Looks like after a good sleep you eventually shared some useful advice. Well done for finally contributing. Useful advice or not, it still doesn't take away from the fact that you're a complete roaster clapa
 
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… 1.5vols is a useless carbonation target for virtually all beers. …
Hum, that's odd, I've got two beers on with only 1.1 volumes (approx.) …
20190814_111239_WEB.jpg
(… I'd keep your voice down if I was you!).
… But even then, as per BJCP guidlelines (and what would they know?!), 1.5vols even for those lower carbed styles is still under-carbonated! …
I made this mistake too. The BJCP only mention "high", "medium" and "low" carbonation. It is others that interpret the BJCP's scrawling that add fanciful details (usually foreigners and not Brits … like in Beersmith who have British Best Bitter down as a minimum of 1.6 volumes :laugh8:).

Well you got your "blazing argument". I hope I'm meeting your expectations? Although I'm not a very good antagonist, I know, I'm sorry about that.
 
Hum, that's odd, I've got two beers on with only 1.1 volumes (approx.) …
Yes but it looks like you're dispensing through a beer engine? Thus you'll likely have a sparkler which churns up your beer to make it palatable. Dispense that out of a normal tap and I'd hate to imagine what it would be like. What's more is that anyone with a beer engine has a particular tendency for "British" beers - the warm, flat CAMRA sort. I for one don't sit in that category, so maybe that's where our differences lie.

I'll leave you with your low volume beer and I'll stick to my well carbed beer. It's personal preference after all. So keep doing what you're doing @peebee and enjoyathumb..
 
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