how many Corny kegs will a 5lb tank do?

[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?

 

[tracer bullet]

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

This?

Indeed.

 

[Airborneguy]

Great thanks!

 

[bracconiere]

well i just swapped my 20lb tank, unfurtantly i forgot to grab my scale. got home to find it's only 17.5lbs....

 

[The Mad Brewer]

Well after all this flat beer I'm just looking for a good place to take a leak.

 

[bracconiere]

Well after all this flat beer I'm just looking for a good place to take a leak.

you could always have done this! post a picture of the head in what are you drinking now!

 

[BigDave1303]

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

I question this when I exchanged my last co2 bottle. I was told its the pressure remaining not the fill level. I used to work for the ambulance service, all our oxygen bottles show the amount of gas remaining not the pressure. Don't know why o2 & co2 are different.

 

[doug293cz]

I question this when I exchanged my last co2 bottle. I was told its the pressure remaining not the fill level. I used to work for the ambulance service, all our oxygen bottles show the amount of gas remaining not the pressure. Don't know why o2 & co2 are different.

Oxygen (& nitrogen, hydrogen, helium, argon, etc.) all remain as gases when compressed, and the pressure is proportional to the amount of gas in the cylinder. CO2 is an odd duck, as it liquefies when compressed, so in a full cylinder you have mostly liquid CO2, as well as some gas in the headspace. Thus you have liquid and gas in equilibrium with each other. Whenever this is the case, the pressure depends only on the temperature of the CO2, not how much there is. So, changing the temperature of the CO2 cylinder will change the pressure. When the liquid is gone, then the CO2 gas behaves more other gases, and the pressure is proportional to the amount of CO2 in the cylinder. So, when the gauge starts dropping (at constant temperature) that means all the liquid CO2 is gone, and your tank is almost empty.

Brew on

 

[Graham H]

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.

I think Duotight upgraded to a newer plastic, specifically to address this issue.

 

[The Mad Brewer]

Spoke to my Brew shop guy today, He had some good advise, 1st disconnect the In connection at the keg end (I m not sure what you call them) and put the end in a glass of water wioth Co2 on, if there is a leak there they will bubble, then as my kegs empty, during cleaning put some pressure on the keg and turn it upside down in a bucket of water, an look for bubbles.
If the taps or the connection at the out end leaks I should have a pool of beer, if I disconnect the out connection at the keg if something is leaking I should see beer bubbles. then spray and bubble test the rest.
Also try disconnecting the in at the Kegs and let them sit for 3 days and check for pressure. Just turning off the valve (what I was doing) isn't valid as negative pressure can be there and can keep it from leaking with the valve off. I did all these except the upside down keg test in a bucket.
No leaks.

The other variable is the tank is in the Keezer at temps of 40F I moverd this out and the gauge should go up. On my next fill I will defiantly check weights.

 

[Airborneguy]

I set to work this morning immediately after I got home from hunting. Pipe dope fixed the manifold end nut leak, but when I charged the system I found another damned leak on the valve off the manifold for the line I’d been using. I could’ve sworn I’d check all of them. Well I pipe doped up that sucker too, and SO FAR, everything looks good. I supposed I’ll know in a few hours if my pressure is still dropping. Fingers crossed.

Thanks all for the help.

 

[BigDave1303]

Thanks for t

Oxygen (& nitrogen, hydrogen, helium, argon, etc.) all remain as gases when compressed, and the pressure is proportional to the amount of gas in the cylinder. CO2 is an odd duck, as it liquefies when compressed, so in a full cylinder you have mostly liquid CO2, as well as some gas in the headspace. Thus you have liquid and gas in equilibrium with each other. Whenever this is the case, the pressure depends only on the temperature of the CO2, not how much there is. So, changing the temperature of the CO2 cylinder will change the pressure. When the liquid is gone, then the CO2 gas behaves more other gases, and the pressure is proportional to the amount of CO2 in the cylinder. So, when the gauge starts dropping (at constant temperature) that means all the liquid CO2 is gone, and your tank is almost empty.

Brew on

Thanks for explaining this. My pressure gauge sits just above 50 bar from new until almost empty. During the summer heatwave the pressure went up to approx 80 bar & dropped back to normal after the heatwave.

 

[balrog]

when the gauge starts dropping (at constant temperature) that means all the liquid CO2 is gone, and your tank is almost empty.

Brew on

My pressure gauge sits just above 50 bar from new until almost empty. During the summer heatwave the pressure went up to approx 80 bar & dropped back to normal after the heatwave.

(at least) one post by @day_trippr has a chart showing tank pressure vs fill here. I think I can drop it here

 

[Bobby_M]

You cannot use the high pressure gauge to watch for gas loss, AT ALL. It's basically binary and doesn't move until the liquid is all gone. The way you check IF you have a leak is to disconnect all the QDs from the kegs. Set your regulator pressure to a round number, say 30psi. Shut the tank valve off and see if the low pressure gauge bleeds down from 30psi. If it holds perfectly for an hour, you don't have a leak in any of the gas plumbing. Of course that doesn't diagnose any keg leaks.

 

[seatazzz]

You cannot use the high pressure gauge to watch for gas loss, AT ALL. It's basically binary and doesn't move until the liquid is all gone. The way you check IF you have a leak is to disconnect all the QDs from the kegs. Set your regulator pressure to a round number, say 30psi. Shut the tank valve off and see if the low pressure gauge bleeds down from 30psi. If it holds perfectly for an hour, you don't have a leak in any of the gas plumbing. Of course that doesn't diagnose any keg leaks.

^This. If you have a system with NO leaks, your high pressure gauge should never move until the liquid co2 starts to be used up, i.e. converts to gas (liquid=pressure, gas=no pressure). Sounds like you're finding more small leaks every time one gets found and fixed. The best way to detect leaks, is to go about it systematically; as @Bobby_M says above, start with the tank/regulator, and the valve on the regulator closed. Then work your way down the line; next, you would have the line open from the regulator to the manifold but all the manifold valves CLOSED. Depending on how many valves your manifold has, test each one, with the others closed. No leaks? Ok! Next is the connectors on the lines to the keg; if you are using worm clamps, be careful about tightening them too much, as they can cut the line if too tight. For duotights, disconnect them and inspect the line for cracks or big scratches; I have them, and removing/reattaching them multiple times can wear the lines out (I use evabarrier line). No leaks there? Next it's the disconnects (assuming you are using corny kegs). They can fail, oh yes I know. Using a spritz of starsan each time you attach them helps the moving parts stay lubricated and connect better. Now the fun part; the keg itself. Keg o-rings (not just the big one for the lid, but all of them) are cheap and easily replaced. Use the soapy water spritz to check the entire top of the keg, from the pressure relief valve, the posts, and the lid. The best way to do this is to have a way to submerge the entire keg in water, which isn't always feasible; I consider it a last-ditch effort if all signs point to the keg being the issue. Another culprit that I just recently discovered is the lid itself; if it doesn't seal tight enough, you're going to lose co2 from under the lid no matter how much keg lube is used. All eight of my kegs are used, some quite old; a couple of them will NOT seal with certain lids. A quick fix I found was to take the feet off the lid, and reduce the space inside each foot with something that will handle the pressure. I used hard plastic sewing pin heads because that's what I had, but it has worked well for the two carbonation lids I got from Amazon, that didn't want to play well with two of my kegs. This is a tough one to find, especially if you force carbonate; the higher pressure with force carbonating will seal the lid, but once that pressure is dropped to serving pressure, the lid will loosen and there goes your co2. Hope this helps.