how many Corny kegs will a 5lb tank do?

[The Mad Brewer]

I have 3 and my CO2 seems to go fast, I tightned all connectiosn an looked for leaks but still doing it. I have been turning off the Co2 at the tank but its a pain everytime I want to pour a beer. Any one have some advise?

 

[khannon]

I think conventional wisdom says that 5# should dispense 6-8 5 Gallon Kegs IIRC. If you are force carbing it will be less.

Edit:

I don't really know where I got that other than the top of my head thinking I read it somewhere once. Doing a little digging, I'm seeing everything from a 5# tank doing 15 kegs to a reference of ~0.2oz per gallon pushed, would would equate to 1oz per keg which would allow a 5# keg to push ~80 kegs worth of beer?

At the last event I did though, someone told me that their soda-stream canister(14oz) would push just under 2 5 Gallon kegs, so that is probably why I am thinking that ~5 times as much would push ~5 times as much beer. I guess all of this assumes a full "Fill" as well.

 

[Airborneguy]

I’m trying to figure this out again as well. I did have a leak, but I fixed it quickly. Still thinking this tank may only get me through 2 kegs. I hope I remember how to deal with this stuff again quickly!

 

[odie]

all depends on volumes of CO2, how much purging you did, serving pressure, etc...

 

[JoeSpartaNJ]

I once got 11 kegs out of a 5lb tank. That included carbing and serving.

 

[The Mad Brewer]

ya something is leaking, I just replaced the tank an its in the red - low again. I added one new kegged beer, purged it a couple time quick and shut the valves off to the other 2 kegs while I carbbed it.

 

[brewbama]

I don’t count how many kegs I get on a tank but I can say the last time I filled my 5# tank was Jul ‘22. I anticipate I will see the new year come and go prior to needing a refill.

 

[redrocker652002]

I have gotten about 5 or 6 kegs so far out of my 5lb tank. Like someone else said, that includes carbing and serving.

 

[The Mad Brewer]

The other thing I noticed when I put a new tank on is that it's already just above the red line. I usually just do a tank exchange with my local Brewer store So I'm going to talk to my guy and see what the deal is otherwise I might take it and just get it filled

 

[bracconiere]

i get about 68 kegs off a 20lber? (my last swap was 12-16-21)....i've poured 3,685 pours on it, it's still got a bit of life, but the gauge is starting to drop...

figuring around 54 pours a keg? i've noticed a lot of the time my 20lb swaps i'll only get 13lbs when i get home and throw it on my scale, so i've started taking my scale with me to the welding shop.....

i would say i KNOW i pour 11 drinks a day, and it takes 0.2oz to do it...takes me about 1.2oz to burst carb a keg...

 

[The Mad Brewer]

i get about 68 kegs off a 20lber? (my last swap was 12-16-21)....i've poured 3,685 pours on it, it's still got a bit of life, but the gauge is starting to drop...

figuring around 54 pours a keg? i've noticed a lot of the time my 20lb swaps i'll only get 13lbs when i get home and throw it on my scale, so i've started taking my scale with me to the welding shop.....

i would say i KNOW i pour 11 drinks a day, and it takes 0.2oz to do it...takes me about 1.2oz to burst carb a keg...

Good idea.
I will need a fill again in a month if I'm stingy with what little I have left. But on next fill I will weigh the tank in the car. I don't want to accuse the shop because they are my only local source. So I will talk to them1st if it is indeed low. Maybe their supplier is chiseling. I dont think they make any money on the Co2 exchange but provide it as a service to its customers

I triple checked all connections and they are tight.

 

[bracconiere]

my leak detector...

https://www.ebay.com/itm/4024399029...jql2FGVgdL1Yb9qUDq+UGqKTtj|tkp:Bk9SR4Dl8tuQYQ

 

[tracer bullet]

I triple checked all connections and they are tight.

Right, but - are they sealing? You may have missed one of those cone shaped little plastic washers or some other gasket, or have one that's cracked or scratched.

 

[The Mad Brewer]

my leak detector...

https://www.ebay.com/itm/4024399029...jql2FGVgdL1Yb9qUDq+UGqKTtj|tkp:Bk9SR4Dl8tuQYQ

Nice thank you

 

[The Mad Brewer]

Right, but - are they sealing? You may have missed one of those cone shaped little plastic washers or some other gasket, or have one that's cracked or scratched.

That was my next thought, maybe i would leave CO2 on one at a time and see if I can narrow it down then take apart and check. I dont want to proactivly do that and loose any CO2…its precious right now. HAHA or maybe just just the valve off to each and wait a coulple days and see if any wont pour or are flat.

 

[The Mad Brewer]

Nice thank you

Oh its a scale, I thought it was an actual leak or pressure tester

 

[tracer bullet]

I was thinking the lines themselves, how the regulator attaches to the tank, etc. but yeah could be the kegs themselves with a leaky gasket.

Looked this up from the internet:

A pound of liquid CO2 in a tank contains 8.741 cubic feet of gas, so a 20lb. cylinder would hold 175 cubic feet CO2, and a 5lb. cylinder would hold approximately 44 cubic feet CO2

5 gallons is actually only about 2/3 (.67) cubic feet. It's hard to believe but true. The keg has a little more space than 5 gallons but it gives an idea. Let's say you purge the keg once (1 volume), the beer transfers and then you carbonate it (2.5 volumes). Then you fill it up with CO2 during serving (1 more volume). So you're up to about 4.5 volumes per beer. Something slightly more than 3 cubic feet of CO2 per beer.

Divide that into 44 and... I don't expect to cover a full 14 beers per 5lb tank, but it gives you an idea of what you might expect in a perfect scenario.

@odie and @JoeSpartaNJ were on this track I think, I just wanted to do some quick math on it.

 

[hawkwing]

i get about 68 kegs off a 20lber? (my last swap was 12-16-21)....i've poured 3,685 pours on it, it's still got a bit of life, but the gauge is starting to drop...

figuring around 54 pours a keg? i've noticed a lot of the time my 20lb swaps i'll only get 13lbs when i get home and throw it on my scale, so i've started taking my scale with me to the welding shop.....

i would say i KNOW i pour 11 drinks a day, and it takes 0.2oz to do it...takes me about 1.2oz to burst carb a keg...

Is that dispensing only or carbonating too? Are they 5 gallon kegs? I seem to recall an estimate of 1 lbs of CO2 is approximately required to carbonate and dispense a 5 gallon keg.

 

[bracconiere]

Is that dispensing only or carbonating too? Are they 5 gallon kegs? I seem to recall an estimate of 1 lbs of CO2 is approximately required to carbonate and dispense a 5 gallon keg.

both?

figuring residule co2 from fermentation and adding an extra volume?

 

[odie]

I have about 8 20# tanks lined up ready to go. Not gonna worry about it.

 

[doug293cz]

If you ferment a beer at 65°F and atmospheric pressure, it will contain 0.88 volumes of carbonation at the end of fermentation. If you want to carbonate to 2.5 volumes, you will need to add 2.5 - 0.88 = 1.62 volumes of additional CO2. 1 volume of CO2 is equal to 1.977 g/L or 0.264 oz/gal. Therefore, to add 1.62 volumes of CO2 to 5 gal of beer requires:

CO2 added for Carbonation = 5 gal * 1.62 volumes * 0.264 oz/(gal*volume) = 2.14 oz​

To maintain 2.5 volumes at 40°F serving temp, you need to set the CO2 pressure to 12 psi. At 12 psi the vacated keg volume will contain (12 + 14.7) / 14.7 = 1.82 volumes of CO2. Therefore, to push 5 gal of beer requires:

CO2 to push = 5 gal * 1.82 volumes * 0.264 oz (gal*volume) = 2.4 oz​

​

So, to carbonate and push 5 gal of beer requires 2.14 oz + 2.4 oz = 4.54 oz of CO2. So, 5 lb of CO2 can carbonate and push 5 lb * 16 oz/lb / 4.54 oz/keg = 17.6 kegs. This does not allow for any CO2 use for purging kegs, leakage, or any other use, and any such use will lower the number of kegs carbonated and served.

To avoid having to purge kegs with bottled CO2, you can use fermentation CO2 to purge kegs. This requires a fermenter that will hold at least a couple of PSI pressure without leaking - so not a plastic bucket. You also need to do closed transfers that do not expose the beer to any air, or allow any air to enter the keg during the filling process.

Using CO2 for purging will significantly reduce the number of kegs you can carbonate and serve with a given amount of CO2. Also, very often CO2 cylinders are not filled to rated capacity.

Brew on

 

[bracconiere]

If you ferment a beer at 65°F and atmospheric pressure, it will contain 0.88 volumes of carbonation at the end of fermentation. If you want to carbonate to 2.5 volumes, you will need to add 2.5 - 0.88 = 1.62 volumes of additional CO2. 1 volume of CO2 is equal to 1.977 g/L or 0.264 oz/gal. Therefore, to add 1.62 volumes of CO2 to 5 gal of beer requires:

CO2 added for Carbonation = 5 gal * 1.62 volumes * 0.264 oz/(gal*volume) = 2.14 oz​

To maintain 2.5 volumes at 40°F serving temp, you need to set the CO2 pressure to 12 psi. At 12 psi the vacated keg volume will contain (12 + 14.7) / 14.7 = 1.82 volumes of CO2. Therefore, to push 5 gal of beer requires:

CO2 to push = 5 gal * 1.82 volumes * 0.264 oz (gal*volume) = 2.4 oz​

​

So, to carbonate and push 5 gal of beer requires 2.14 oz + 2.4 oz = 4.54 oz of CO2. So, 5 lb of CO2 can carbonate and push 5 lb * 16 oz/lb / 4.54 oz/keg = 17.6 kegs. This does not allow for any CO2 use for purging kegs, leakage, or any other use, and any such use will lower the number of kegs carbonated and served.

To avoid having to purge kegs with bottled CO2, you can use fermentation CO2 to purge kegs. This requires a fermenter that will hold at least a couple of PSI pressure without leaking - so not a plastic bucket. You also need to do closed transfers that do not expose the beer to any air, or allow any air to enter the keg during the filling process.

Using CO2 for purging will significantly reduce the number of kegs you can carbonate and serve with a given amount of CO2. Also, very often CO2 cylinders are not filled to rated capacity.

Brew on

i swear i love your sexy talk!

 

[doug293cz]

i swear i love your sexy talk!

I wish my wife was as turned on by my postings as you are.

Brew on

 

[bracconiere]

i get about 68 kegs off a 20lber? (my last swap was 12-16-21)....i've poured 3,685 pours on it, it's still got a bit of life, but the gauge is starting to drop...

figuring around 54 pours a keg? i've noticed a lot of the time my 20lb swaps i'll only get 13lbs when i get home and throw it on my scale, so i've started taking my scale with me to the welding shop.....

i would say i KNOW i pour 11 drinks a day, and it takes 0.2oz to do it...takes me about 1.2oz to burst carb a keg...

I wish my wife was as turned on by my postings as you are.

Brew on

it just always feels like, compared to me, you've got a waxed chest. and are all oiled up! and i'm watching a bodybuilding competition, but for the brain!

feel free to tell your wife i said that!

 

[balrog]

I triple checked all connections and they are tight.

Right, but - are they sealing? You may have missed one of those cone shaped little plastic washers or some other gasket, or have one that's cracked or scratched.

This times infinity. Even the slightest, tiniest, most inconceivably small leak, times hours and days equals disaster of epic proportions, dogs and cats living together, real wrath of God type stuff. You really need to liquid/soap/starsan leak test **EVERY** connection, including kegs, taps, everything.

 

[balrog]

If you ferment a beer at 65°F and atmospheric pressure, it will contain 0.88 volumes of carbonation at the end of fermentation. If you want to carbonate to 2.5 volumes, you will need to add 2.5 - 0.88 = 1.62 volumes of additional CO2. 1 volume of CO2 is equal to 1.977 g/L or 0.264 oz/gal. Therefore, to add 1.62 volumes of CO2 to 5 gal of beer requires:

CO2 added for Carbonation = 5 gal * 1.62 volumes * 0.264 oz/(gal*volume) = 2.14 oz​

To maintain 2.5 volumes at 40°F serving temp, you need to set the CO2 pressure to 12 psi. At 12 psi the vacated keg volume will contain (12 + 14.7) / 14.7 = 1.82 volumes of CO2. Therefore, to push 5 gal of beer requires:

CO2 to push = 5 gal * 1.82 volumes * 0.264 oz (gal*volume) = 2.4 oz​

​

So, to carbonate and push 5 gal of beer requires 2.14 oz + 2.4 oz = 4.54 oz of CO2. So, 5 lb of CO2 can carbonate and push 5 lb * 16 oz/lb / 4.54 oz/keg = 17.6 kegs. This does not allow for any CO2 use for purging kegs, leakage, or any other use, and any such use will lower the number of kegs carbonated and served.

To avoid having to purge kegs with bottled CO2, you can use fermentation CO2 to purge kegs. This requires a fermenter that will hold at least a couple of PSI pressure without leaking - so not a plastic bucket. You also need to do closed transfers that do not expose the beer to any air, or allow any air to enter the keg during the filling process.

Using CO2 for purging will significantly reduce the number of kegs you can carbonate and serve with a given amount of CO2. Also, very often CO2 cylinders are not filled to rated capacity.

Brew on

This calculation should be a sticky. Also the post about calculating purging. One man's opinion.
And, for the record, I am able to purge a keg with fermenter CO2 using a bucket fermenter and a plastic big mouth bubbler, **HOWEVER**, I have to be really Really REALLY persnickety about every seal along the way.

 

[bracconiere]

You really need to liquid/soap/starsan leak test **EVERY** connection, including kegs, taps, everything.

nope, you need to keep your tank on scale, preferably accurate to the GRAM, DAMN IT! but it's still better then bottling!

and remember don't panick when you achieve this, gravity is a thing too!

 

[CanaHomebrew]

ya something is leaking, I just replaced the tank an its in the red - low again. I added one new kegged beer, purged it a couple time quick and shut the valves off to the other 2 kegs while I carbbed it.

Do you use duotight connectors? Once I had a leak because I overtightened a duotight, and a very very small crack developed on the connector, one I couldn't even see doing the spray test. Once I replaced it, it seemed to improve.

 

[balrog]

Do you use duotight connectors? Once I had a leak because I overtightened a duotight, and a very very small crack developed on the connector, one I couldn't even see doing the spray test. Once I replaced it, it seemed to improve.

Some folks can use scads of them without issue in "always on" systems.

 

[Airborneguy]

Looks like I have my system all squared away (for now). It’s been holding strong at 600lbs @ 41F for about 12 hours now.

I’m leaving for the weekend soon. Should I shut the tank off? I have one beer on tap currently.

Man I really wish I hadn’t forgotten all of this…

 

[Bad Bubba]

You definitely have a leak. I use a spray bottle with a few drops of Dawn dish soap and spray it on all connections when looking for a CO2 leak. You will find it quickly as it will foam at the leak point. I have started doing this whenever I put a new keg in the keezer because I find that the gas ball lock connector sometimes does not fully seal.

 

[balrog]

Looks like I have my system all squared away (for now). It’s been holding strong at 600lbs @ 41F for about 12 hours now.

I’m leaving for the weekend soon. Should I shut the tank off? I have one beer on tap currently.

Man I really wish I hadn’t forgotten all of this…

I would shut off the tank, but that's just me.
Remember also that some regulators leak, and some tank cap-nut-valve-shafts leak unless all the way on or off.
That's why every single one of these conversations eventually mentions debugging by isolating different sections of the system to find the leak(s).

 

[Airborneguy]

Yeah I’m gonna shut it. Thanks!

 

[Airborneguy]

Gave it one more check before shutting off the tank… I found another tiny leak at the end of the manifold. Re-tefloned the nut, no luck. I’ll have to deal with this when I get back.

 

[Airborneguy]

There’s yellow tape on some of the fittings. Is that for CO2? Maybe that’s why?

 

[The Mad Brewer]

This times infinity. Even the slightest, tiniest, most inconceivably small leak, times hours and days equals disaster of epic proportions, dogs and cats living together, real wrath of God type stuff. You really need to liquid/soap/starsan leak test **EVERY** connection, including kegs, taps, everything.

I blame solar flares

 

[tracer bullet]

Yellow is supposedly for "gasses" but generically it's just PTFE ("Teflon") and has little if any difference from white.

It's a good spot for liquid pipe dope. The tapes are more like a lubricant and let the threads engage farther without getting stuck. NPT seals rely on the threads mushing together. The liquid dopes get in there and fill the nooks and crannies far better.

After you get back from your travels I'd take the opportunity to disassemble, clean, and reassemble everything.

 

[balrog]

Yellow is supposedly for "gasses" but generically it's just PTFE ("Teflon") and has little if any difference from white.

It's a good spot for liquid pipe dope. The tapes are more like a lubricant and let the threads engage farther without getting stuck. NPT seals rely on the threads mushing together. The liquid dopes get in there and fill the nooks and crannies far better.

After you get back from your travels I'd take the opportunity to disassemble, clean, and reassemble everything.

And then leak test.
Everything.

 

[hawkwing]

I recall reading in another post that starsan has a negative effect the Duotight fittings. It can cause them to fail prematurely. Might have been from soaking. So maybe to be safe use dish soap and water instead to test for leaks.

 

[Airborneguy]

I’m reluctant to take apart connections that aren’t leaking.

This?