CO2 empty after 3 days?

[newmabt]

First off, I'm not brewing beer... I am simply carbonating water for the family, but I'm new to this. Bought an old dual-tap kegerator off FB Marketplace.
- Corny keg with pin-locks
- 5 lb CO2 tank
- Regulator

The first keg, I could hear and see a leak in the lid. The CO2 emptied about the same time the keg did, so it lasted for 1 keg only. I replaced the keg and do not see or hear any leaks in the new one. But, the CO2 went empty after 3 days of force carbonating at 30 psi.

One caveat - when I first connected the CO2, the gas rushed out of the pressure relief valve at 30 psi, as it was stuck in the open position. I tried this 4 or 5 times, no more than 2 seconds each time before I just decided to replace the PRV. Could that 10 seconds of release emptied the tank that fast?

 

[camonick]

Could that 10 seconds of release emptied the tank that fast?

No. You still have a significant leak somewhere.

 

[newmabt]

No. You still have a significant leak somewhere.

Any advice on how to find it? Do I have to get the tank refilled to troubleshoot?

 

[camonick]

CO2 leaks can be like finding a needle in a haystack sometimes. Yours sounds like it should be fairly obvious.

Do I have to get the tank refilled to troubleshoot?

Yes, you’ll need a new tank of gas so you can pressurize the system again. I’d double check all connections with a wrench or pliers. If the kegs were used, I’d replace every o-ring. If your regulator doesn’t have an integrated o-ring on the tank stem, are you using a nylon washer in that connection?
If you have any flare connections that are metal to metal, do you have one of these nylon washers between those connections? You can use a spray bottle with a starsan solution to spray each connection or soapy water will work in a pinch too.

 

[marc1]

Spray something bubbly at all connections and possible leak points. Star San is great because it's no rinse food contact, soapy water works too. You will need more CO2 for this.

 

[bobeer]

try the soapy water trick... Take a sponge and dab soapy water on all the connections. Your leak sounds like it'll be pretty obvious as to where it's coming from. If you can't find it then I'd trade it in at an exchange/fill place or you can have them tested for $50 i think at any gas or oxygen store.

 

[Stonehenge360]

Also, make sure you open the co2 valve all the way. It has internal seals in the open and closed positions, but it is possible for it to leak around the stem in the “middle” position. I made this mistake my first time and blew a 10lb bottle In two weeks.

 

[newmabt]

Thanks all. To answer several of the question:
- Yes, there is a nylon washer on the regular stem
- I had already replaced all o-rings on the keg
- The CO2 tank is new, as my local Fire & Safety store replaced it when I first took it in 2 weeks ago (rather than refill it)

I have Starsan... what is the ratio for the solution for this test?

 

[camonick]

I have Starsan... what is the ratio for the solution for this test?

Same solution you use for your equipment.

 

[TechFanMD]

You could also have multiple small leaks. If you have a compressor you could use that for leak finding if CO2 is very expensive and or hard to get there but not the best choice.

Turn off the valve on the outlet of the regulator, turn the tank on, note the input and output pressure, turn the tank off, look in 4 hours. If either gauge dropped the leak is before the valve.

You can also pressurize the empty keg and turn it upside down in a sink or storage tote full of water and see where bubbles are coming out.

 

[szap]

If you have Swivel nuts instead of barbs on your quick connect, make sure they are tight

 

[bracconiere]

i know the bubble method is typical, but i like having shut off points, and tracing back....if i shut off one point, then turn it back on with my eye on the low pressure gauge, and if it drops even slightly, i found my leak.....and if it's the regulator itself, then shutting off both the kegs and tank, and watch to see if loses pressure....

 

[bracconiere]

damn, i seriously did try using the search funtion such that it is....but a 5lb tank assuming it acctually has 5lb of co2 is 80oz's...and 5gallons of co2 at 1 ATM is 1.23oz's....i have no idea how many volumes 30psi would give it...i tried but failed......


but yeah it should last a lot more then one keg.....

 

[mashpaddled]

Couple of things for you to consider with quick connects on pinlocks.

As said above if you have swivel nuts instead of barbs (or barbs that screw on swivel nuts) it is really easy to loosen them enough to get a leak. If you have barbs double check they are not barbs on swivels because that may be your problem.

Check the fit of the quick connect to the post. Pinlock kegs have all sorts of lengths of posts and "universal" or replacement posts some homebrew shops sell might screw on the post but do not sit flush with the keg. As a result when you lock the quick connect to the pins the quick disconnect does not sit flush with the keg and it can wobble if there is tension on the hose or you turn the hose and it tips the quick connect slightly.

I chased an off and on leak for months in which I figured out I was getting leaks from both of these issues.

 

[Bobby_M]

The first thing you can do to isolate the source of the leak is to disconnect the pinlock QD from the keg, pressurize the regulator to 30 PSI and then close the tank valve. See how long it will hold at 30 like that. If your regulator has a shutoff valve prior to hitting the hose, close that for the first leakdown test described above. It it holds 30 for an hour, open the valve and let it pressurize to the QD. If it still holds 30 for an hour, your leak is either between the QD and keg or the keg itself.

 

[newmabt]

I wanted to provide an update: I have not been online much the last 2 days, so I missed some of these comments and have not tried all.
I did test with the Star San solution, but did not see any bubbles anywhere. Then, I decided to buy some new hose clamps, since the original ones were crimped in an oval shape over the barbs.
I proceeded to force carbonate at 30 psi starting Tuesday night. I still have CO2 in the tank, 40 hours later, so it's better than before, though I'm still not confident I've found the problem.
I do feel like the gas pin-lock QD can be wiggled slightly, but there is no danger of it coming loose, if that's the ultimate concern.

 

[bracconiere]

I proceeded to force carbonate at 30 psi starting Tuesday night. I still have CO2 in the tank, 40 hours later, so it's better than before, though I'm still not confident I've found the problem.
I do feel like the gas pin-lock QD can be wiggled slightly, but there is no danger of it coming loose, if that's the ultimate concern.

how do you know the tank has co2? High pressure gauge or weight?


and if you have any vasoline, maybe try lubing the gas post lightly......and when is the last time you replaced your o-ring?

(also i've recently read here pin locks use a slightly fatter o-ring?)


edit: before i learned o-ring replacement was normal maintenance, vas was my best friend!

edit #2: as far as the weight thing, if you want to know if you solved your leak...disconnect the tank and weigh it on a digital bathroom scale....hook it back up wait a few days, i'm assuming, it's easier to go with out bubbly water then beer here, and then repeat and look for a change....

edit: i have recently learned vasoline is bad for o-rings. keg lube, proof in process.

 

[newmabt]

OK. Here's the latest:
It's been 4 days since I started force carbonating. I turned down to 10 psi yesterday morning. Last night, I tried to pour some and nothing came out. I shook the keg up for 10 seconds, then I was able to pour a glass. I have no idea what that means.

For the question above, I knew I was out of CO2 before because of the high pressure gauge. Today, that gauge looks fine.

 

[LittleRiver]

...If you have a compressor you could use that for leak finding....

Only if your air line is equipped with filters to remove the oil and other impurities that come out of an air compressor.

 

[newmabt]

Back at it today. I simply picked up the water and gas lines from the keg to a height equal to the top of the keg and then I was able to get a pour. Could the lines being too long, such that they loop on the bottom of the fridge be a reason for my problems? The pressure is set to 15 psi at the moment.

 

[VikeMan]

Could the lines being too long, such that they loop on the bottom of the fridge be a reason for my problems? The pressure is set to 15 psi at the moment.

How long is the beer line? And what's its inner diameter?

 

[camonick]

Can you provide pictures of your setup? Something still sounds way off. I was going to ask the same question as Vikeman above. We went from loosing a 5 lb CO2 tank in 3 days with no confirmation of solving the problem, to “I can’t pour anything after force carbonating @ 30 psi for 40 hours.”
Have the poppets been replaced on the keg posts with universal ones as opposed to OEM styles? Sometimes the springs are to stiff on the universal ones and the plunger on the disconnect can’t fully depress it. Your liquid line would have to be quite long to reduce your flow to nothing. Length of gas line is irrelevant.

 

[newmabt]

The lines are standard liquid and gas lines from a brew shop (sorry, I do not remember the diameters, as I am at work).
I have found that if I turn the pressure to about 16 psi, I can get a slow pour of carbonated water. If I turn that down to 10-12 psi, nothing comes out. The high-pressure gauge is just barely dipped down into the "red" zone, but not all the way to 0. I will send pictures when I get home today.

 

[TechFanMD]

Only if your air line is equipped with filters to remove the oil and other impurities that come out of an air compressor.

Most people at home have oilless compressors and any debris is usually minimal....and you'll be re-sanitizing the keg anyway.

 

[bracconiere]

The high-pressure gauge is just barely dipped down into the "red" zone,

as soon as the HP gauge drops at all, the tank is empty. unless room temp swings a bit.

not sure if this was allready said. co2 in a tank is liquid, it has a constant pressure, to remain a liquid.

 

[marc1]

as soon as the HP gauge drops at all, the tank is empty. unless room temp swings a bit.

not sure if this was allready said. co2 in a tank is liquid, it has a constant pressure, to remain a liquid.

Yup - pressure dropping means no more liquid CO2 in the tank to make up for the gas that was used. UNLESS maybe you put the tank in the fridge? That throws the reading way off.

I also agree with camonick above - please provide good pictures of the entire setup so we can see what's going on. We may be missing something.

 

[jddevinn]

Not on the leak but regarding the pouring.... what temp do you have the fridge set at? I never have problems with beer freezing but have frozen kombucha in the beer lines that have touched the side of the freezer.

 

[TheBluePhantom]

Agree on the freezing possibility. I have had soda in kegs freeze when the kegs touch the side. Always keep a gap over an inch.

On the leak, I no longer trust any hose clamps except stepless oetikers. I have has worm drives and regular oetikers leak a lot. since I do soda I test my lines at 40 psi, gas and beer. Never seen a leak with stepless oetiker. quite reasonable on eBay. Put a touch of keg lube on your post orings, it is cheap.