CO2 for Kegging - Options?

[Nztayls]

I'm going to make the jump from bottling to kegging. Whats the best option for CO2? Where do you get bottled CO2 from?

I see that you can use Soda Stream bottles to do this, which might be cheaper. How many kegs does one bottle do?. 

Trying to work out the most cost-effective option. Appreciate any advice!

[mattd2]

Do not use sodastream if you want a cost effective solution. Force carb and serve one soda stream bottle will do just over one keg. It will do just under 3 if you prime the kegs. At $11 a bottle it starts getting expensive.

[Crusader-Rob]

matt: When you say prime the kegs, you mean sugar in the keg. if so to get 2.5 volumes which is probably about average, how much do i need, as I've read that you dont need the standard bottling amount when you do priming in the keg.

[mattd2]

I think I use around 100g of dextrose for approx 15 litres. Purge the head space and then set at 10 psi - then leave in a warm place for the suger/yeast to do it''s job. I think the general rule of thumb in the US is 3 oz of suger (compared to 5 oz when bottling). It seem to work alright but I don't know if I am still carbing some from the bottle.

[Des Ross]

Best solution is take the plunge and buy a decent size CO2 bottle and regulator, make sure you get a one way check valve as insurance against beer being forced back up the CO2 line! A couple lengths of tubing and a picnic dispensing tap and your in business! Personally I don't force carb and just cool the keg to 3-5 C and set regulator to 10 psi for about one week. Lots of reading here in 'The Library' or google...can also do a search on UTube for some excellent video .

[mattd2]

Just to be sure: by force carb, are you meaning the 30 psi for a day or so method? If so I agree with you that for sanity stick with the set at serving pressure and leave for a week or two. Technically this is still force carb, just a safer way to avoid overcarbing issues.

[Smiffy]

When "force carbonating" you have to know what you are aiming for (in terms of volumes) then find out (I use a spreadsheet I found) to see what pressure CO2 you need for the current temperature of the beer. Then you can either leave the gas connected for a few days, or you can shake the keg to achieve equilibrium (between the gas and the gas in solution) in a much shorter time.

If you then put your keg in the fridge, you need to look up the new pressure for the new temperature, and that will be your serving pressure. Then you can use pipe length/size or a restricter to achieve a sensible flow.

For the example of 4C and 10psi, that gives 2.34 volumes, so if carbonating at 20C you would need 29psi.

If you start from a "serving pressure" to get the right flow you will end up constantly adjusting it to stop the beer being all head one day and flat a few days later.

[mattd2]

Sorry if I cause more confusion, by serving pressure I mean the pressure that corresponds to the correct carb level at the temperature you are serving (the 10 psi in you example). From my reading/experience there are basically 3 main ways to carb a beer (rough overview):

Prime: Like you do when bottling, add a bit of sugar and leave it somewhere warm(ish) for a few weeks (the amount of sugar is usually less than bottling because you seal the keg and then purge the headspace with CO2)

Force carb (quick): With the beer cool put it in the keg and set the pressure at approx 30 psi for a day in the fridge. Then bled off the pressure and set it to what you serve at (10 psi in above example). Some do the shake method so that you don't have to wait the day but this can cause even more problems with overcarb.

Force Carb (slow): Put the beer in the keg and then put it in the fridge at the correct pressure for the carb level, wait about 2 weeks for the beer to fully carb.

The problem with the qick method is it can be easy to overcarb, especially for beginners. Although your method sound interesting as you shouldn't overcarb if you hit it with 30 psi at room temp so it is more like the slow method. How long does it usually take you to get it fully carbed?

[Smiffy]

My reply was probably based more on my own experiences than anything else, and it took me a few days to work out that adjusting the serving pressure has an immediate effect on how fast the beer comes out of the tap (instant reward) but then a couple of days later, the carbonation level had changed. The other thing I learnt from experience is that putting pressure in the keg, then disconnecting it, then coming back a few days later, is that the gap above the beer does not hold enough CO2 to do much at all. So you either have to leave it connected to the regulator or keep connecting it, or get it all done asap. With only one regulator I didn't want to leave it connected, so adopted the fast but controlled method, which can't over-carbonate if you use the right pressure for the temperature.

I don't want to put the keg in the fridge at that point (because I rotate three kegs, but only two fit in the fridge), but I don't want to leave the beer in the keg un-carbonated, firstly because I want it to be ready to serve as soon as it is chilled, and second I think the beer has less chance of going off than if it's left flat (but I think that might just be an incorrect feeling).

My room temperature carbonating is done over a couple of hours. Shake for 5 minutes, leave for an hour, repeat. You know when it is done because when you shake the keg you no longer hear gas passing through the regulator.

[mattd2]

Yeah, your way sounds like a good way to do it without resulting in overcarb'd kegs... I really need to get a proper CO2 cylinder cause these sodastream ones do suck!

 

[Sam]

Porirua cylinder testing is a good place for co2 cylinders. From memory $250 for a converted fire extinguisher (3.5kg?) (painted silver) and they also have larger (5kg?) brand new ones (personally I wouldn't go for the 5kg as besides from price unless you shut the bottle valve every time after using a 5kg will just cost you more if something like your co2 disconnect starts leaking)

[welly]

It's a while since I bought my converted fire extinguisher (2009?) but this is what I paid at Wormalds in Petone for a 3.2kg cylinder;

Cylinder $20.00
Pressure test $45.00
Recharge $44.65
Valve $65.00

These prices do not include GST.

I have had the cylinder refilled and tested at Wormalds with no issue.

Cheers

Welly

[Glynn Foster]

I have a 7kg cylinder and end up paying $40 for a refill at Wormalds (this week) - I think it's a pretty standard price no matter what size you're filling. Bottles need retesting every 5 years, but the price above was what I was quoted too. Also, the guys out there like cash :)