Question about co2 draining speed

[downtown3641]

I may be a little paranoid right now, but with good reason. I started carbonating my first kegged brew last night. I woke up this morning to an empty co2 tank. I found a pretty sizable leak where the gas line connects to the regulator. I've fixed it, reconnected the gas, and tested every possible place I could think of for leaks. How fast should the dial drop on the gauge that indicates how much co2 is left in the tank while I'm actively carbonating? I have it set at 12psi. I feel like the needle is dropping fairly quickly. I'm hoping that I just used a bit of gas while testing and that will account for the loss. Again, I'm probably just being paranoid because I don't want to go drop another $24 on a tank swap.

 

[stratslinger]

It shouldn't noticeably drop, not to carbonate a single keg.

That said - are you storing your keg inside or outside your kegerator? If inside, as your cylinder cools the pressure inside will drop significantly. Doesn't mean you're losing gas, just that CO2 stored at cooler temperatures generates a lot less pressure than it would at higher temperatures.

 

[downtown3641]

That sounds like the right explanation. The tank was stored in a shed at my LHBS. I brought it home and started working on the leak then put the tank inside the kegerator. I guess it's been far too long since my high school physics class.

 

[scsnick]

What size tank do you have? The high side gauge is pretty much useless. It will only drop into the red when the tank is about to run out. The only way to know how much co2 you have is to weigh it. It does not show you how much co2 you hqve left like your fuel gauge in your car. It only shows the amount of pressure available. The pressure in the tank will stay the same right up until just before it runs out when you are literally "running on fumes." It should not move at all during normal use. When you put the tank in a cold environment the pressure will drop, but you will still have the same amount of co2 available. 5lbs is 5lbs, whether its at 80 degrees or 30 degrees.

Even if you gave a 5lb tank, people seem to average between 5-10 kegs with force carbing. Check all of the seals on the keg itself and the regulator as well. Make sure the lid is seated as well.

Edit- if you would really like to know the amount of co2 that you have left in the tank you can weigh it. Look on the side of the tank and there will be a "TW" stamped into the metal near the top of the tank with a number after it. That's is your tare weight, or the weight (in pounds) of the cylinder itself when empty. You put the tank without the regulator on it onto a scale, subtract the tare weight, and that number will be how many pounds of co2 you have remaining in the tank.

 

[edmanster]

If you have a old bathroom scale weigh your new tank with the regulator attached so you have a start weight.. Then if you have any question to how much your loosing or how close to empty you are it's just a weight measurement away!!

 

[downtown3641]

Thanks for the info, folks. Unfortunately, I don't have a scale to weigh the tank. But, I double checked everything I could think of and didn't find any additional leaks. Hopefully, I'm good to go now.

 

[downtown3641]

I guess the drop in pressure with the drop in temperature also explains why I just had to adjust the regulator because the psi had dropped while I was at work.

 

[edmanster]

The regulator psi should not change with temp!!

 

[downtown3641]

Hmmm. Sounds like I have more troubleshooting ahead of me. The regulator PSI dropped about four points over the four hours between my lunch break and when I got home from work.

 

[Raenon]

The regulator psi should not change with temp!!

That's contrary to every thread on the subject I've read here, and also contrary to both of my CO2 tanks, and each regulator, which have both gone down in pressure with temperature drop (from upwards of 1000psi to as low as 500 psi, which is down in the "fill soon" area on the dial), and went back up when I let them warm up.

What will not change due to temperature differences is the mass, or weight, of the CO2, hence the suggestion for the scale as being the only way to really tell beyond waiting until it goes empty (which is a rather pricey measuring system!)

 

[downtown3641]

That's contrary to every thread on the subject I've read here, and also contrary to both of my CO2 tanks, and each regulator, which have both gone down in pressure with temperature drop (from upwards of 1000psi to as low as 500 psi, which is down in the "fill soon" area on the dial), and went back up when I let them warm up.

What will not change due to temperature differences is the mass, or weight, of the CO2, hence the suggestion for the scale as being the only way to really tell beyond waiting until it goes empty (which is a rather pricey measuring system!)

I was talking about the gauge for pressure being applied to the keg. I assume the guy who responded was, as well.

 

[edmanster]

Right!! I wasn't talking about the tank pressure, I ment the outlet pressure! My bad!!

 

[JuanMoore]

Hmmm. Sounds like I have more troubleshooting ahead of me. The regulator PSI dropped about four points over the four hours between my lunch break and when I got home from work.

Did you happen to adjust the pressure down without venting the keg? If so, you probably adjusted lower than you think, and the CO2 is just being absorbed into the beer, accounting for the drop in pressure. Unless you have a fancy newer regulator, you always need to adjust up to the desired pressure, never down.

That's contrary to every thread on the subject I've read here, and also contrary to both of my CO2 tanks, and each regulator, which have both gone down in pressure with temperature drop (from upwards of 1000psi to as low as 500 psi, which is down in the "fill soon" area on the dial), and went back up when I let them warm up.

What will not change due to temperature differences is the mass, or weight, of the CO2, hence the suggestion for the scale as being the only way to really tell beyond waiting until it goes empty (which is a rather pricey measuring system!)

I think you're confusing regulator pressure and tank pressure. We've already established in this thread that the tank pressure will change with temperature. The amount of gas the regulator releases to your kegs (regulator pressure) however should remain constant, even with temperature fluctuations. And I certainly hope that you're not putting 500-1000psi of pressure on your beer.

 

[edmanster]

Are you shutting the tank off after pressurizing? If so, the co2 is just being absorbed into the beer!!

 

[downtown3641]

Right!! I wasn't talking about the tank pressure, I ment the outlet pressure! My bad!!

Outlet pressure! I was looking for the proper terminology.

Any thoughts on the outlet pressure drop? I have no idea where a possible leak could be, as I checked every connection point I could find.

 

[downtown3641]

Did you happen to adjust the pressure down without venting the keg? If so, you probably adjusted lower than you think, and the CO2 is just being absorbed into the beer, accounting for the drop in pressure. Unless you have a fancy newer regulator, you always need to adjust up to the desired pressure, never down.

We have a winner! I've been fine tuning a bit. I just got the fridge on Sunday and I've been trying to get a good read on the temperature, which has been difficult because I've also been opening it a lot as I've been troubleshooting. I've been attempting to adjust the regulator accordingly. I think I'll knock that off until the next batch.

 

[Raenon]

I think you're confusing regulator pressure and tank pressure. We've already established in this thread that the tank pressure will change with temperature. The amount of gas the regulator releases to your kegs (regulator pressure) however should remain constant, even with temperature fluctuations. And I certainly hope that you're not putting 500-1000psi of pressure on your beer.

I did read "regulator pressure" as "tank pressure", you're right.
Tank vs outlet is probably offers far more clarity.

Though I'm sure 1000psi would help some of those who just have to have their beer carbed immediately, I'd be willing to bet my pipeline that the keg would be a little fussy about that prospect

 

[JuanMoore]

We have a winner! I've been fine tuning a bit. I just got the fridge on Sunday and I've been trying to get a good read on the temperature, which has been difficult because I've also been opening it a lot as I've been troubleshooting. I've been attempting to adjust the regulator accordingly. I think I'll knock that off until the next batch.

You can adjust all you want, but when you want to lower the pressure, turn the pressure way down, then release the pressure from the system (either the relief valve on the regulator or on the keg), and then slowly increase the pressure to creep up on the desired setting. Otherwise the gauge is reading the higher pressure that's still in the keg/system, rather than the new lower applied pressure.

Or buy one of the newer fancy micromatic regulators that automatically vents the excess gas in the system when you turn the knob down.

 

[JuanMoore]

Though I'm sure 1000psi would help some of those who just have to have their beer carbed immediately, I'd be willing to bet my pipeline that the keg would be a little fussy about that prospect

Ha! I wouldn't want to stand anywhere near someone attempting that, but it might be fun to watch from a distance.

 

[downtown3641]

One more question: should I be concerned about a gas leak in my serving line. I'm pretty sure the answer is no, since the beer is served from the bottom of the keg. But, again, just making sure I don't have to buy another co2 tank anytime soon.

 

[edmanster]

One more question: should I be concerned about a gas leak in my serving line. I'm pretty sure the answer is no, since the beer is served from the bottom of the keg. But, again, just making sure I don't have to buy another co2 tank anytime soon.

Are you saying the co2 is coming out of the beer in your serving line? If so, that's just a sign that the volume of co2 is greater in the keg compared to the serving pressure which means the beer is over carbonated or the setup is unbalanced in terms of serving line length...

 

[downtown3641]

Are you saying the co2 is coming out of the beer in your serving line? If so, that's just a sign that the volume of co2 is greater in the keg compared to the serving pressure which means the beer is over carbonated or the setup is unbalanced in terms of serving line length...

No. I was just making sure that, all things being normal, I didn't have to concern myself with losing co2 via the serving line. I just pulled a small sample of my beer today, mainly to test the balance of the system, and the thought popped into my head. It seems like a silly question after I had typed it, but figured I'd ask anyway.

 

[edmanster]

No. I was just making sure that, all things being normal, I didn't have to concern myself with losing co2 via the serving line. I just pulled a small sample of my beer today, mainly to test the balance of the system, and the thought popped into my head. It seems like a silly question after I had typed it, but figured I'd ask anyway.

Yup, beer from the bottom of the keg so you did answer your own question..lol... Wait till you're so thirsty for your first pint of the day and blow foam so stock pile a keg or 2 in your pipeline.. Also you will still have a bed of yeast fallout in your keg so dont lift or wiggle to see how much is left or you'll mix it up.. Oh, and enjoy :cheers:

 

[downtown3641]

Yup, beer from the bottom of the keg so you did answer your own question..lol... Wait till you're so thirsty for your first pint of the day and blow foam so stock pile a keg or 2 in your pipeline.. Also you will still have a bed of yeast fallout in your keg so dont lift or wiggle to see how much is left or you'll mix it up.. Oh, and enjoy :cheers:

Already trying to figure out how another keg or two and a dual regulator setup fits into my budget over the next month or so.

 

[edmanster]

Already trying to figure out how another keg or two and a dual regulator setup fits into my budget over the next month or so.

Classifieds and craigslist is where I got all my stuff... My lucky one was 4 coke kegs for $40. 4 years ago