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How to force carb in a week?

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So - I have 3 kegs to carb before my birthday party in 8 days. My kegerator got delayed in transit so I'm using my fermentation fridge which sadly doesn't fit two kegs and the gas cylinder.

I put the first keg on at 25 psi @ 2C for 24 hours on Wednesday, reduced it to 13psi @ 8.5C yesterday. I was thinking another day or two and that one will be ready, repeat for other two kegs.

Now I fear I don't have enough time, that they will need longer.

I have a splitter and two QDs so can do two kegs at once.

Any views on whether I should:
- stick to plan A maybe with psi or temp adjusted
- carb the second two at once at room temp
- drill a hole in the fridge and carb two in that (I need to serve from it at the party so that may in inevitable, can seal it afterwards)
 
So - I have 3 kegs to carb before my birthday party in 8 days. My kegerator got delayed in transit so I'm using my fermentation fridge which sadly doesn't fit two kegs and the gas cylinder.

I put the first keg on at 25 psi @ 2C for 24 hours on Wednesday, reduced it to 13psi @ 8.5C yesterday. I was thinking another day or two and that one will be ready, repeat for other two kegs.

Now I fear I don't have enough time, that they will need longer.

I have a splitter and two QDs so can do two kegs at once.

Any views on whether I should:
- stick to plan A maybe with psi or temp adjusted
- carb the second two at once at room temp
- drill a hole in the fridge and carb two in that (I need to serve from it at the party so that may in inevitable, can seal it afterwards)

8 days is plenty of time for set and forget carbing whether you do it in the fridge or out. When I carb cold I usually intend to wait 7 days, but end up trying it after 5 and it's fine.

13psi at 8.5C is slightly unusual. Is that the temperature you intend to serve it at?

Assuming you want them at 2.2vol, I'd put 23psi at 20C on the two you haven't carbed yet. Periodically pull the QDs off, drop the pressure to 13psi and see if the keg at 8.5C will take any more gas. After a couple of days taste the keg at 8.5C. If that's good take it out of the fridge, and put the others in. When they've chilled taste and adjust carbonation as necessary.

Whether to drill the fridge probably depends on whether you're likely to use it as a keg fridge once the kegerator arrives.

Happy Birthday.:mug:
 
Thanks for the feedback! First kegging experience so concerned I am going to make a mistake.

8.5C was the serving temp, yes. Well I set my temp controller to 8 or 9C and it allows a variation of 0.5C before cutting power so it's sitting around 8.5. The carb chart says 13psi gets me 2.3 vols or so.

Anyway, follow up questions please, sir:
- how do you tell if the keg will take more gas?
- how long to put the 2 kegs on at 23psi? Any shaking required? How long and vigorous?
- when you say drop it to 13psi at 8.5, that's putting the kegs in the fridge which will take some time to get down to temp so that's not supposed to be a quick check right?
- one of the beers I only kegged on Wednesday, good to carb now?

I won't use the fridge for serving once the kegerator arrives, will be back to the fermentation fridge. But I want at least two kegs cold during the party so don't have the cylinder inside. I figure I can seal the hole afterwards ok.
 
The carb chart says 13psi gets me 2.3 vols or so.

Yep, that's right. If this is the first time you've used your regulator, you might want to bear in mind that the pressure gauges are not always accurate, and the tables are designed for an ASBC 'standard beer'. You might have to tweak the pressure until you get the degree of carbonation you want.

Anyway, follow up questions please, sir:
- how do you tell if the keg will take more gas?

If it takes more gas you'll hear gas flowing through the regulator when you connect the QD.

- how long to put the 2 kegs on at 23psi? Any shaking required? How long and vigorous?

Two or three days should be enough. Shaking will speed up carbonation as will laying the keg on its side. The danger with that is that if the pressure in the keg increases and/or the regulator pressure drops then you force beer into the regulator - not good. If you want to shake the keg, keep shaking until you can't hear gas flowing through the regulator.

- when you say drop it to 13psi at 8.5, that's putting the kegs in the fridge which will take some time to get down to temp so that's not supposed to be a quick check right?

No. I was suggesting that periodically (a few times a day) you ...

* take the QDs off the kegs outside the fridge
* drop the reg pressure to 13psi
* attach the QD to the keg in the fridge at 8.5C and see if it takes more gas. If it it doesn't then that suggests that it's reached equilibrium. Otherwise you'll need to keep doing this.
* then take the QD off the cold keg, turn the reg pressure back up to 23psi and reconnect the QDs to the room temperature kegs

- one of the beers I only kegged on Wednesday, good to carb now?

Yep. No harm in carbing it ASAP.

I won't use the fridge for serving once the kegerator arrives, will be back to the fermentation fridge. But I want at least two kegs cold during the party so don't have the cylinder inside. I figure I can seal the hole afterwards ok.

Ok. It's always handy to have the option. Just so long as you can avoid drilling through any plumbing in the side of the fridge. If you're not sure how to do that, PM me.
 
Thanks for the splendid advice, I have applied it with varying degrees of success.

I tried to beer that was in the fridge at 13psi/8.5C, I got a bit of head on it but otherwise pretty flat. I decided to force carb it a bit, had it on its side on my knees agitating it, did that for 5 minutes @ 25 psi, then left it until tonight. It's better but doesn't seem carbed enough yet. It's cloudy being the first couple of glasses so can't see how bubbly it is, but it doesn't seem zingy. But better. So planning to force some more into it tomorrow.

I hooked up the two room temp kegs overnight on 25psi, visited them this morning to find a bit of beer in the line (not backed up to the regulator though, just a bit). I recall one of the kegs I filled quite high up so I am assuming it's that one. I've unhooked that one and put it in the fridge, I plan to try it on a lower pressure - any other advice for dealing with an overfilled keg (aside from dumping a litre of beer?). The other one I have hooked back up and it seems happy enough.

So - I am speculating I can force carb the first keg tomorrow up to pressure, do the second one slowly for 5 days and force carb the third.
 
any other advice for dealing with an overfilled keg (aside from dumping a litre of beer?).

I can't suggest much beyond "be careful". Obviously the problem occurs when the pressure in the keg is greater than the regulator pressure. This can occur with fluctuating keg temperature, or (more likely) when you reconnect the QD and you set the regulator pressure slightly lower.

In the first case keeping the temperature steady is all you do. In the second case venting a bit of pressure through the pressure release valve on the lid gives some insurance.

You should have a check valve between the QD and the reg, but don't rely on it - they seldom work.
 
Add priming sugar and spund (or seal and monitor pressure). It’ll be done in a couple days at room temp. Better carbonation and very low packaged oxygen.
 
Add priming sugar and spund (or seal and monitor pressure). It’ll be done in a couple days at room temp. Better carbonation and very low packaged oxygen.

I'm probably a bit far in now for that to be an approach with a known outcome, I've had the room temp keg plugged in for two days, would be hard to guess how much sugar from here. But if my gas powered efforts are painful, I'll be interested.

Anyway, I managed to force carb the full one ok without incident. I put it on its side with the gas post on the top, seemed to go fine. That was this morning. I tried it tonight, not bad. Pretty cloudy which isn't surprising so hard to tell exactly how much fizzing was going on but it poured quite well and tasted nice. Back in the fridge with it, will try it again later in the week.
 
I'm probably a bit far in now for that to be an approach with a known outcome, I've had the room temp keg plugged in for two days, would be hard to guess how much sugar from here. But if my gas powered efforts are painful, I'll be interested.

Natural carbonation IMHO is the best way to go for kegging and is waaaay under hyped. If you get a spunding valve you can just set the pressure to match the actual temperature and desired carbonation level. I normally use about 2-3oz of priming sugar per keg and that always seems to be more than required. Aim just a little high and any excess pressure will be vented. Your serving CO2 tank will last A LOT longer too.
 
Best to wait until you've got plenty of time if you want to try natural carbing in the keg. Most sources recommend two weeks not 2 days - there's no reason why it would be any quicker than bottle conditioning. Not everyone agrees that natural carbonation is better, and oxygen scavenging is only useful if there's a flaw in your process that introduces oxygen to start with. Also you may have to trim your dip tube to keep it out of the sediment, and there are other downsides to having yeast in your keg.
 
Best to wait until you've got plenty of time if you want to try natural carbing in the keg. Most sources recommend two weeks not 2 days - there's no reason why it would be any quicker than bottle conditioning. Not everyone agrees that natural carbonation is better, and oxygen scavenging is only useful if there's a flaw in your process that introduces oxygen to start with. Also you may have to trim your dip tube to keep it out of the sediment, and there are other downsides to having yeast in your keg.

I would agree that you should plan ahead to do this and have the right tools on hand (simple and inexpensive), but i do disagree with some of your points:

1. Time - if you rack reasonably soon after the beer has reached terminal gravity, the yeast will still be active and will happily, and quickly, consume all those simple sugars. I have pressure gauges on my kegs when i do this and you can see about 90% of the conditioning is complete in 2 days, and its only another day or two after that when it doesn't rise any further. Now if you've left that yeast on the cake for 4 weeks, then yah, it'll probably take longer. Your best bet is to rack when the beer has just finished (better yet, about 2-3 gravity points before finishing then you don't need priming sugar). I know a lot of people like to let the beer ride on the cake for a while, but it's just not necessary. I used to do 28 day primaries on everything and produced some decent clear beer. Now for ales i'm usually racking to kegs in ~3 days and the flavor and longevity is vastly improved. Game changer on IPAs.

2. Oxygen - even in the most diligently purged closed systems oxygen is a real problem and is virtually impossible to fix via mechanical means. Yeast is the best way to bring dissolved oxygen to near 0. Not looking to derail this into a low oxygen thread, but it's a real concern and conditioning is a real way to improve longevity of the beer.

3. Dip tubes - I'm usually through the sludge after the first half pint or so. I wouldn't suggest shortening them for serving kegs.

Good luck to the OP!
 
If it takes more gas you'll hear gas flowing through the regulator when you connect the QD.

I'm finding this easier said than done in my lack of experience. Possibly it's being drowned out by my fridge when I open the door (but I can turn that off I guess) but if it's happening, it's pretty quiet and/or quick. In my mind I'd think if the beer isn't carbed, the pressure in the headspace is going to be a few psi less than what the regulator is set to, and it's not going to take long to get to the 13psi I've got it set to, so hearing it flowing I don't get.

I do hear it when I force carb so I know what it sounds like at least.

It's also hard to judge by the beer itself since the first few glasses are cloudy and I can't see whether it's bubbling or not. I don't think it's fizzed enough but I can't observe it, it's just my tastebuds to go on, and having not done it before, I am unsure.
 
It's also hard to judge by the beer itself since the first few glasses are cloudy and I can't see whether it's bubbling or not. I don't think it's fizzed enough but I can't observe it, it's just my tastebuds to go on, and having not done it before, I am unsure.

Taste (and mouthfeel) should be all you need.

Given you're short on time you might be better to try the crank and shake approach. Rack reg the pressure up to 30psi and attach the cold keg. Put the keg on its side and shake for 3 to 5 mins. Put it back in the fridge for 5 min. Pour a sample. It will probably be mostly foam. Ignore that, but see whether the liquid tastes carbonated enough. If not repeat, and be careful with the over-filled keg.
 
Party day!

The keg I had put on for 5 days at room temp and 23 psi I tried last night. It had visible bubbles but enough quite enough so I've cranked that up a bit.

The first keg was pouring 2/3 foam so I degassed it a couple of times and last night it poured better but I think undercarbed so cranked that a bit more too.

The overfilled keg is currently warm so I've had that back on at 23 psi without incident. Can't put it in fridge also so planning to put it in ice to keep it a bit cool so I can transfer it to the fridge when one finishes.

Fingers crossed they are all drinkable!
 
The pressures discussed here seem really weird. I'm not saying they are wrong, if they work then great, but maybe regulator accuracy isn't great or sample method/dispense is still being fine tuned?

In a pinch we'll force carb kegs with top pressure in 40 hours at 22psi at cellar temperature (10C?). It'll definitely over carbonate if left longer, the method balances a need for speed with a need to not over or under shoot and handily means if you set it monday night, you shut it off wednesday morning, wednesday night then to friday morning, friday night then to sunday morning and so on.

We batch carbonate a smaller 1,100L tank which struggles to get down below 3C. Once it is at temperature it takes about 2 days at 22psi using a bottom sinter. 22psi is a lot, but there is wetting pressure of the stone as well as hydrostatic pressure to compensate for so knock about 10psi off that for what the tank sees.

We carbonate several larger 2,200L, 2,400L, 2,600L tanks using top pressure alone (please don't make fun!) and because we can hold these at 0C reliably we can carbonate the lot pretty much in the same day at 22-24psi if needed (working pressure of the tanks) though we don't really need to, 10psi still gets us there in 2 days.

My point is that in all of these cases the theory supporting carbonation charts for a set and forget method works and it works pretty fast. I often leave stuff for 5 days, sometimes several weeks, but it never actually needs that long with the gas on and if it isn't there something else is wrong.

Every stumbling block I've had on the way has been down to sampling method. It is next to impossible to get an accurate sample out of a pressurised tank without the back pressure involved in a well designed keg line. We looked at a pig tail stainless steel glycol jacketed coil for sampling, in effect several meters of microbore tubing to provide the necessary back pressure and to super chill the beer. It is easier to just fill a keg and put it on the bar, 99% of the time we are there now anyway.
 
Natural carbonation IMHO is the best way to go for kegging and is waaaay under hyped. If you get a spunding valve you can just set the pressure to match the actual temperature and desired carbonation level. I normally use about 2-3oz of priming sugar per keg and that always seems to be more than required. Aim just a little high and any excess pressure will be vented. Your serving CO2 tank will last A LOT longer too.

Yeah i too now prime my kegs. I'm away working for weeks at a time so it just makes sense.

I have a 20lb tank i expect it to last a few years!
 
The pressures discussed here seem really weird. I'm not saying they are wrong, if they work then great, but maybe regulator accuracy isn't great or sample method/dispense is still being fine tuned?

In a pinch we'll force carb kegs with top pressure in 40 hours at 22psi at cellar temperature (10C?). It'll definitely over carbonate if left longer, the method balances a need for speed with a need to not over or under shoot and handily means if you set it monday night, you shut it off wednesday morning, wednesday night then to friday morning, friday night then to sunday morning and so on.

We batch carbonate a smaller 1,100L tank which struggles to get down below 3C. Once it is at temperature it takes about 2 days at 22psi using a bottom sinter. 22psi is a lot, but there is wetting pressure of the stone as well as hydrostatic pressure to compensate for so knock about 10psi off that for what the tank sees.

We carbonate several larger 2,200L, 2,400L, 2,600L tanks using top pressure alone (please don't make fun!) and because we can hold these at 0C reliably we can carbonate the lot pretty much in the same day at 22-24psi if needed (working pressure of the tanks) though we don't really need to, 10psi still gets us there in 2 days.

My point is that in all of these cases the theory supporting carbonation charts for a set and forget method works and it works pretty fast. I often leave stuff for 5 days, sometimes several weeks, but it never actually needs that long with the gas on and if it isn't there something else is wrong.

Every stumbling block I've had on the way has been down to sampling method. It is next to impossible to get an accurate sample out of a pressurised tank without the back pressure involved in a well designed keg line. We looked at a pig tail stainless steel glycol jacketed coil for sampling, in effect several meters of microbore tubing to provide the necessary back pressure and to super chill the beer. It is easier to just fill a keg and put it on the bar, 99% of the time we are there now anyway.

In my experience to force carb a cold corny keg you can do it in 1-2 days at 40 psi. It will not be over carbed, just check it every day.
 
In my experience to force carb a cold corny keg you can do it in 1-2 days at 40 psi. It will not be over carbed, just check it every day.

It isn't the same as leaving the pressure on at the correct level until the beer is both conditioned and carbonated, but honestly if you can rack a beer into a corny (beer cold crashed to 1C so pretty frosty) and put head pressure onto it, gently put it onto its side so the head space becomes quite large and roll it back and forth you can watch the regulator drop as the co2 dissolves into the beer. You can do this for as long as you want until it stabilises and theoretically get the whole thing done in minutes.

Quarter barrel kegs carbonate with top pressure for us in 40 hours at 22psi because the head space is fixed. It'll be the same for you with 2 days at 40psi and a corny. It is handy to figure to have the technique dialled in with that fixed variable.
 
It isn't the same as leaving the pressure on at the correct level until the beer is both conditioned and carbonated, but honestly if you can rack a beer into a corny (beer cold crashed to 1C so pretty frosty) and put head pressure onto it, gently put it onto its side so the head space becomes quite large and roll it back and forth you can watch the regulator drop as the co2 dissolves into the beer. You can do this for as long as you want until it stabilises and theoretically get the whole thing done in minutes.

Quarter barrel kegs carbonate with top pressure for us in 40 hours at 22psi because the head space is fixed. It'll be the same for you with 2 days at 40psi and a corny. It is handy to figure to have the technique dialled in with that fixed variable.

i rather not dial in. I make homebrew. :mug:
 
It isn't the same as leaving the pressure on at the correct level until the beer is both conditioned and carbonated, but honestly if you can rack a beer into a corny (beer cold crashed to 1C so pretty frosty) and put head pressure onto it, gently put it onto its side so the head space becomes quite large and roll it back and forth you can watch the regulator drop as the co2 dissolves into the beer. You can do this for as long as you want until it stabilises and theoretically get the whole thing done in minutes.

Quarter barrel kegs carbonate with top pressure for us in 40 hours at 22psi because the head space is fixed. It'll be the same for you with 2 days at 40psi and a corny. It is handy to figure to have the technique dialled in with that fixed variable.
For carbonation, headspace volume is irrelevant. The only variables that matter are: CO2 partial pressure, beer temperature, and the ratio of gas-beer interface area to beer volume. Increasing the interface area increases carbonation rate. Bubbling CO2 thru the beer drastically increases the gas-beer interface area. Shaking also increases the interface area.

Edit: Forgot one other variable - the current carbonation level of the beer (CO2 concentration in the beer.)

Brew on :mug:
 
Last edited:
For carbonation, headspace volume is irrelevant. The only variables that matter are: CO2 partial pressure, beer temperature, and the ratio of gas-beer interface area to beer volume. Increasing the interface area increases carbonation rate. Bubbling CO2 thru the beer drastically increases the gas-beer interface area. Shaking also increases the interface area.

Edit: Forgot one other variable - the current carbonation level of the beer (CO2 concentration in the beer.)

Brew on :mug:

Fair point. For accuracy when I say head space I should actually say surface area for beer/gas interface. Quarter and half barrel kegs have a slightly convex top like corny kegs. When they are almost completely full the interface area is tiny compared to when they have lost 500ml and if we have to force carbonate this can throw things out of whack. Variable fill level within this portion has resulted in a few returns within batches.

We now run out a little beer to a known weight. Once you are out of the domed portion the surface area remains constant if the kegs are vertical and as such it works the same every single time.
 
Fair point. For accuracy when I say head space I should actually say surface area for beer/gas interface. Quarter and half barrel kegs have a slightly convex top like corny kegs. When they are almost completely full the interface area is tiny compared to when they have lost 500ml and if we have to force carbonate this can throw things out of whack. Variable fill level within this portion has resulted in a few returns within batches.

We now run out a little beer to a known weight. Once you are out of the domed portion the surface area remains constant if the kegs are vertical and as such it works the same every single time.
Yes.

Brew on :mug:
 
Anyway .. a post-party update. So, the set and forget beer had the best carbonation easily. The other two were overcarbed but we made do. Frequently they poured half-foam, even with no gas attached, and the best pours were when we left the gas off for a while.

But overall was a grand success - 1 keg tapped and the other two left with very little to go.

And learning was set and forget is probably the way to go!
 

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