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jeeppilot

Well-Known Member
Joined
Jan 5, 2012
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Location
Memphis
I’m struggling with my new keg setup. I have a keezer that I serve from and most of my beer is coming out flat. I force carb, using the “set and forget” method. I’m using 10 psi at 40F and letting my beers carb at least two weeks before. I have referenced the literature for balanced systems and have 8.5 feet of 3/16” tubing for each faucet. The tube is coiled on top of each keg and completely enclosed in the cold keezer.

If I pour my beer “hard”, meaning flat into the glass, I get no head, little bubble formation and what does form dissipates very rapidly. Soon the beer is flat. I do currently have 1 keg that pours with head that last for an hour! The others, not so.

Could my o-rings be bad? Is there something else I’m missing? Out of ideas. Thanks!
 
Unless you have a rather large tank, if you've had this new setup running for two weeks and haven't emptied your CO2 cylinder then the good news is you're probably not leaking significant gas.

Plus you have one beer that pours nicely.

Are all of the kegs on the same regulator? What's the style of the "good" keg vs the others?

Cheers!
 
Unless you have a rather large tank, if you've had this new setup running for two weeks and haven't emptied your CO2 cylinder then the good news is you're probably not leaking significant gas.

Plus you have one beer that pours nicely.

Are all of the kegs on the same regulator? What's the style of the "good" keg vs the others?

Cheers!

It’s a 5# tank and I haven’t lost any gas in months, let alone weeks. So yeah, that’s good! All the kegs are on a 4 way manifold attached to a single regulator. They are all original pin-lock kegs, but not exactly sure what make.
 
Excellent - you're already ahead of most new keggers.

By "style" I was referring to the beer, not the kegs. Before I started dispensing my stouts using beer gas they would take at least half again as much time to carb up as my pales and lagers, which I attributed to an effect of the significantly higher FG (20-something points vs 10-something).

If you have the one beer that is nicely carbed vs the other(s) that isn't(aren't), what if anything is different between them?

Cheers!
 
Excellent - you're already ahead of most new keggers.

By "style" I was referring to the beer, not the kegs. Before I started dispensing my stouts using beer gas they would take at least half again as much time to carb up as my pales and lagers, which I attributed to an effect of the significantly higher FG (20-something points vs 10-something).

If you have the one beer that is nicely carbed vs the other(s) that isn't(aren't), what if anything is different between them?

Cheers!

Lol, sorry. All three are dark beers, all between 6.5 and 7.5% ABV, with FGs between 1.015 and 1.022. The Cascadian/Black IPA is the one that has a terrific foam and doesn’t seem flat once it’s poured. The others are an Old Chub clone and a bourbon oaked dubbel. The bourbon dubbel has been on gas since September and the Old Chub has been on gas 3 weeks. The bourbon dubbel has SLIGHTLY more carb than the Old Chub but both are downright flat. Although both have some of that carbonation “burn” there are zero noticeable bubbles rising from the beer while in the glass.

I turned up the serving pressure to 12 psi to see if maybe I miscalculated something in my lines. No change.
 
EDIT* So after I turned the regulator up to 12 psi and gave it about 24 hours, the beers pour much better. They seem carbed and have some head to the pour. I’m still fairly convinced my system is “balanced” but I’m concerned that 12 hours with the extra 3 psi made all the difference? Also, a friend of mine mentioned my poppets may be sticking and not allowing the gas to fully charge the beer. Especially at 9 psi. I did not replace my poppets when I got my used kegs. Thoughts?
 
I'm not sure keg post poppets and disconnect plungers are all that sensitive to pressure that dialing up a few extra psi suddenly causes them to "pass gas".
While I always replace all of the O-rings on new-to-me kegs, I only replace poppets if they leak or are obviously damaged as the oem models are pricey little bastids (I'm not a big fan of "universal" springs and poppets).

Anyway...24 hours would be a pretty quick response to your dialing up the pressure. That said, earlier I was trying to avoid what could be the proverbial elephant in the room, but there's the possibility that your regulator low pressure gauge is off by enough to matter.
If you can figure out a way to validate the pressure setting it might be revealing...

Cheers!
 
EDIT* So after I turned the regulator up to 12 psi and gave it about 24 hours, the beers pour much better. They seem carbed and have some head to the pour. I’m still fairly convinced my system is “balanced” but I’m concerned that 12 hours with the extra 3 psi made all the difference? Also, a friend of mine mentioned my poppets may be sticking and not allowing the gas to fully charge the beer. Especially at 9 psi. I did not replace my poppets when I got my used kegs. Thoughts?

So based off of the 24-hour response time, I'm going out on a limb and suggesting that it has nothing to do with dissolved gas. I might suggest looking at your lines and how they are arranged, because what seems to be happening is that there wasn't enough pressure in that one line. Essentially, when fluid moves through a tube, there's an effect called pressure loss (that's what gets the fluid moving in the first place). If there isn't enough pressure, the beer doesn't move fast enough. When it leaves the tap, two things will happen: firstly, the pressure on the beer will drop quickly, and secondly, the beer falling and hitting the glass will provide agitation (the faster the beer is traveling, the better). Both of these will force bubbles out of solution, causing head formation. You can see this in action when it comes to the amount of head formed at the beginning of a keg versus at the end. The last few beers will have significantly less head than the beginning, because the CO2 is having to do extra work on the beer to raise it to the tap (what is called "elevation head"). This lowers the amount of pressure on the beer at the tap exit, and lowers the head thickness and bubble production.


I might suggest a few simple questions, observations, and tests:
1) Was the pour rate on all taps (at the same PSI) the same?
2) Are your lines all laid out the same? Is one all wrapped up at the top, while another reaches down to the bottom? Does one line get close to the cooling coils? Are there any kinks in one?
3) Do you get the same results if you change which beer and gas lines go to each keg?
4) How is your gas system set up? If all of your beers are hooked up to the same manifold at the same pressure, it's possible you could now have some problems with your beer that was pouring properly at 10 PSI. This would also mean that it wouldn't be related to the gauge accuracy.
 
So based off of the 24-hour response time, I'm going out on a limb and suggesting that it has nothing to do with dissolved gas. I might suggest looking at your lines and how they are arranged, because what seems to be happening is that there wasn't enough pressure in that one line. Essentially, when fluid moves through a tube, there's an effect called pressure loss (that's what gets the fluid moving in the first place). If there isn't enough pressure, the beer doesn't move fast enough. When it leaves the tap, two things will happen: firstly, the pressure on the beer will drop quickly, and secondly, the beer falling and hitting the glass will provide agitation (the faster the beer is traveling, the better). Both of these will force bubbles out of solution, causing head formation. You can see this in action when it comes to the amount of head formed at the beginning of a keg versus at the end. The last few beers will have significantly less head than the beginning, because the CO2 is having to do extra work on the beer to raise it to the tap (what is called "elevation head"). This lowers the amount of pressure on the beer at the tap exit, and lowers the head thickness and bubble production.


I might suggest a few simple questions, observations, and tests:
1) Was the pour rate on all taps (at the same PSI) the same?
2) Are your lines all laid out the same? Is one all wrapped up at the top, while another reaches down to the bottom? Does one line get close to the cooling coils? Are there any kinks in one?
3) Do you get the same results if you change which beer and gas lines go to each keg?
4) How is your gas system set up? If all of your beers are hooked up to the same manifold at the same pressure, it's possible you could now have some problems with your beer that was pouring properly at 10 PSI. This would also mean that it wouldn't be related to the gauge accuracy.

The pour rates appear to be the same. The lines are run to coil on top of the keg with just a tiny bit of slack for when I open the lid. (Taps in the collar are mounted to the lid, not the freezer itself) So there should be no issues with lines near cold/warm spots.

It was actually two different beers in two different kegs having the same issue. One poured great, while the other two, not so much so. I have not tried pouring from a different line, but I purged the gas on each keg, then hooked up its respective gas line to listen to the rate and time it took to fill back to pressure. All were roughly the same best as I could tell from the differences in beer volume remaining in each keg.

All beers are hooked to one manifold. I have considered I made two different beers both lacking greatly in head retention. But that doesn’t explain them being flat on top of it.

1. Will a different length gas line affect the pressure delivered to the keg? (We are talking less than 9” at the most between the longest line and the shortest line) My longer gas lines seem to be suffering more, so if that is true, that could be a fix.

2. Perhaps I’ve made an error in my calculations for the balanced system and simply boosting to 12 psi is really where my system should be given my serving lines.

3. I’m going to replace all rubber and poppets in my pre-used kegs just because 1) I should have done it in the first place, 2) it’ll eliminate those factors, 3) it’s cheap to do. I’ll see what happens after that.

Thanks for all your guidance @daytipper and @ hendenburg2
 
Last edited:
It might be illuminating to show a picture of a typical pour, but if the ratio of head to beer at the end of the pour is acceptable I don't think we're looking at CO2 breakout here.

I generally recommend using 1 foot of 3/16" pvc beer line per psi of CO2 - with that CO2 pressure set to maintain the desired carbonation level at the dispensing temperature (reference our favorite carbonation table). For a more detailed/authoritative analysis on line lengths see the only beer line length calculator worth using...

Cheers!
 
I am brand new to kegging, with a single kicked keg under my belt. I asked a lot of questions in this forum, and I have more ideas for the next keg, which I hope to fill soon. But one change that made a big difference for me is also the one that seems to work for you here; I added a few extra pounds of pressure and suddenly the beer tasted a whole lot better.

If the math says x, but your mouth says x + 2, listen to your mouth! You can figure out later why the math let you down.
 
The pour rates appear to be the same. The lines are run to coil on top of the keg with just a tiny bit of slack for when I open the lid. (Taps in the collar are mounted to the lid, not the freezer itself) So there should be no issues with lines near cold/warm spots.

It was actually two different beers in two different kegs having the same issue. One poured great, while the other two, not so much so. I have not tried pouring from a different line, but I purged the gas on each keg, then hooked up its respective gas line to listen to the rate and time it took to fill back to pressure. All were roughly the same best as I could tell from the differences in beer volume remaining in each keg.

All beers are hooked to one manifold. I have considered I made two different beers both lacking greatly in head retention. But that doesn’t explain them being flat on top of it.

1. Will a different length gas line affect the pressure delivered to the keg? (We are talking less than 9” at the most between the longest line and the shortest line) My longer gas lines seem to be suffering more, so if that is true, that could be a fix.

2. Perhaps I’ve made an error in my calculations for the balanced system and simply boosting to 12 psi is really where my system should be given my serving lines.

3. I’m going to replace all rubber and poppets in my pre-used kegs just because 1) I should have done it in the first place, 2) it’ll eliminate those factors, 3) it’s cheap to do. I’ll see what happens after that.

Thanks for all your guidance @daytipper and @ hendenburg2

Any updates/insights/revelations?
 
Any updates/insights/revelations?

The 12 psi seems to be working relatively well. I haven’t yet replaced my poppets and rubber, at this point just a matter of principal, because I’ve been dealing with work and frozen pipes. But I think perhaps my system may just not be as I calculated, combined with my last two beers lacking in head formation and retention. Wish I had something more definitive, but at this point I don’t.
 
Any updates/insights/revelations?

Finally got around to replacing my poppets and all o-rings on my pin-lock kegs. I got a set of universal poppets from Ferroday?? It says the fit pin and ball lock kegs. Two problems... first, some, but not all, of the poppet seals seem to protrude far more than my originals.

IMG_0332.jpg


Second, a couple of them I had a great deal of trouble getting to seat flat. One just wouldn’t. With or without pressure in the keg, this happened.

IMG_0330.jpg


I assume this is most likely the new “universal” poppets being junk. But they were the most expensive of the group and well rated on Amazon. [emoji51] Anyone use Farroday universal poppets and have these issues? Is it possible the issue is actually the posts?
 
Update: I replaced all rubber, and got some universal poppets from NY Brew Supply that worked. The other ones had o-rings that were too small, which caused the problems. Anyway, I’m STILL pouring flat beer. The most recent keg, a brand new one, I naturally carbed the beer in keg. After 3 weeks at 72F I hooked it up and poured a glass. It was warm, but had nice foam, lacing and retention. So I left it to chill and cold age for a few days. Came back a week later and it bubbles the second it hits the glass, but within 5 seconds, no bubbles, head or anything. The beer looks like it would after fermentation. Can’t see any bubbles in the beer or breaking the surface.

I’ve cut my lines back from 10 ft to 5 ft. It pours better, but still ends up flat after a few seconds. Checked all connections for tightness. Checked for temp stratification in my keezer. 38F at my faucets. My next step is to get a keg of someone else’s beer and put it on my system. If theirs doesn’t do it, it’s my beer. If it does, it’s my system but I’m no closer to knowing why. [emoji35][emoji35][emoji35]
 
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