Foam problem with corny keg.

[amends]

Hi everyone,

I recently got a kegging system and have a beer that's been carbonated to about 2.5 volumes of CO2 at about 38 degrees. I don't have a kegerator setup, just a picnic tap on a 5 ft (3/16) beer line. I have it set to 10 PSI (@6000ft Altitude) for dispensing, but everytime I dispense I get all foam UNLESS I vent the CO2 from the headspace first and pour while it refills, which gives me a perfect pour.

My questions are:

What am I doing wrong? Why does venting the headspace give me the perfect pour and carbonation levels I want?

Also, should I be shutting off the CO2 when I'm not dispensing? Is the headspace getting too pressurized between pours (1-2 pours a day)?

I've read a ton of guides on reducing foam, but none of them really apply to me. Basically I just need some tips on using this thing, it's amazing when it works.

 

[day_trippr]

How did you actually carbonate this batch?

Your temperature/CO2 pressure combination is in the ball park and should not be the root cause of your foam problem.

If this is the first time you've used that keg, there may be a problem with the O-ring that is under the flange on the Out dip tube. If that O-ring leaks it will allow CO2 under pressure to flow directly from the keg head space into the beer line, and a classic symptom of that is "spitting" foam at the faucet.

Venting the CO2 pressure to near zero may leave it low enough that there's not enough pressure to sneak through that seal, while leaving just enough pressure in the head space to push beer to your picnic tap.

You could depressurize the keg and remove the Out post, then remove the Out dip tube and inspect the o-ring under the flange for wear/cuts/nicks/etc. You could also try swapping it with the o-ring under the In/Gas dip tube (same size, but that o-ring simply keeps CO2 from escaping from under the post and dip tube into the atmosphere).

For your other question, with a leak-free system set to the appropriate pressure for the beer temperature and desired carbonation level, you should never have to turn off the CO2 as once the carbonation level reaches equilibrium it'll never go any higher. I never turn the gas off on my keezer or carbonation fridge, and don't have foam problems...

hth

Cheers!

 

[amends]

One thing I notice is that the beer line constantly develops tons of bubbles in it. I believe they are CO2 bubbles.

I force carbonated at 30 PSI for two days, then set it back down to about 12 for going on a week now. It dispenses fine sometimes, but other times it does not. All of the O-Rings are brand new, I inspected them before I kegged the beer.

 

[day_trippr]

Ok, that's why that was the first thing I asked: your beer is probably overcarbonated from the burst-carbing. Disconnect the gas line and release the head space pressure frequently. This will allow dissolved CO2 to break out into the head space, lowering the carbonation level. Eventually you'll tame that brew and can put it back on the gas again. If you want to pour a pint while this is going on, connect the gas line with the pressure set to a minimal level, pour your pint, then disconnect the gas line and continue with the burping process...

Cheers!

 

[NorthRiverS]

Make sure the beer line is cold too.

 

[amends]

Beer line is cold.

Honestly I find the carbonation level is perfect (to taste) if I lower the PSI (5-8) to dispense or just pour while releasing gas from the headspace. It was carbonated pretty high at first, but I've had it set to about 12 pretty consistently.

I also want to note that the temperature may fluctuate during the day since this is not refrigerated but in a basement. It sits at 38 most of the time but I wouldn't be shocked if it jumped above 40 during the day. Which a lot of guides said above 40 is bad, and can cause foam. It's never above 40 when dispensing however, but if it got hotter I can see some beer getting out of solution and making the headspace a bit more pressurized than it should be. But even if I clear the headspace at 38 degrees and let it refill at 12 PSI it's still foamy. :/

 

[Cathedral]

You said you don't have a kegerator setup. How are you keeping the keg cool? how are you keeping the line cool?

I do 10' minimum on any line, period. My lines stay inside my kegerator. Everything is cool up to the tap.

If you have major temperature differentials between the keg and the tap, you'll have major foam issues. That's why you want to keep everything at the same temp as much as possible.

Tell us more about your setup, and we'll give you more answers.

EDIT: sorry, apparently you were posting the same time I was, and answered the questions I had!

 

[GilSwillBasementBrews]

I'm betting it's the 5' beer line in the picnic tap. I run 10' lines on all my kegs and do not have foaming issues. The short lines coupled with varying keg temps could easily be cause of you're foaming on pour. As the lines don't have enough resistance to keep the co2 in solution as well as the warmer beer temps also causing CO2 to leave solution easier. I would recommend a more consistent temp control and try 10' beer lines and I think you'll find more consistent pouring results. I keep my kegs at 38F 12 PSI and 10' liquid lines and get good pours with an inch or less head in the glass.

 

[BigFloyd]

At your altitude of 6000ft, I'd start with 15ft of 3/16" beer line and trim it back if needed (it probably will not). I'm at 465ft and 12ft of 3/16" of line, 38*F and 11-12psi work really well.

Two full days at 30psi on chilled beer would likely over-carb it. 24-30 hours at that pressure is normally about right.

 

[amends]

My mini fridge I ordered should be in tomorrow, so hopefully having a regular temperature will help a bit. I think I can get it to the right pressure if I had a more (surely) stable temperature. It just bugs me that I have to tone it down from 12 PSI to around 8 PSI in addition to emptying the headspace everytime I want a pour.

Edit: Yeah, I just checked, it dropped to 35 out there but I have it still sitting at 12 PSI to dispense. Probably makes sense that it would pour right at 8 PSI now that I think about the temperature.

 

[BigFloyd]

You're still going to have to address your line length issue. It will always be a frustrating struggle with 5ft beer line (especially at your elevation). Been there, done that.

 

[amends]

I guess it couldn't hurt to go and grab 15 ft of line or so. I might do that after the keg is empty and I keg the next brew. I'm really just hoping having it at a stable temperature helps, or a mix of everything solves it.

 

[Jupapabear]

I used 2 ft line to test my system: clean and pressure test my kegs. I had actually poured my first few pints with the 2 ft beer line. It was crap. Upgraded like I planned, and knew I already should have, and I'm enjoying my second beer in tap. Get control of your temps and a longer beer line. Then upgrade your picnick tap. You'll be proud. (I'm still on my picknick taps)

 

[raouliii]

You're still going to have to address your line length issue. It will always be a frustrating struggle with 5ft beer line (especially at your elevation). Been there, done that.

.....I'm really just hoping having it at a stable temperature helps, or a mix of everything solves it.

I'm with BigFloyd on this. If you want to FIX this, deal with the beer line length and you won't have to cross your fingers.

 

[Rockn_M]

Having a stable temp will help but not solve the issue. Try increasing you lines to 10ft or dropping the psi.

 

[brewinginCO]

At your altitude of 6000ft, I'd start with 15ft of 3/16" beer line and trim it back if needed (it probably will not). I'm at 465ft and 12ft of 3/16" of line, 38*F and 11-12psi work really well.

Two full days at 30psi on chilled beer would likely over-carb it. 24-30 hours at that pressure is normally about right.

This. I'm at 5000 ft and started with 7ft of 3/16th lines. Couldn't get a proper pour even with excellent temp control at 37-38 degrees. I just put on a 16ft line and it pours great and is only a little slow. I'll probably trim about 1-2 feet off when I change kegs, but I wouldn't say it's necessary.

Also, at higher elevation, we need to apply more keg pressure for a given carbonation level. I'm running around 15psi, and may need to bump it up slightly to carb to my liking.

See this info from New Belgium:
http://www.newbelgium.com/files/Basics of Draught Dispense.pdf
http://www.newbelgium.com/files/CO2 Selection Chart.pdf

 

[amends]

Thanks for the posts everyone! Looks like I need a longer length.

Those are excellent resources, brewinginCO. I'm in Colorado Springs and the altitude seems to definitely be a factor. The intructions I got from the LHBS down here suggest dispensing at 8 PSI with their setup, but I suppose that's because it's 5 ft line. I'll go back and get a longer line today and give it a shot once it's in the fridge.

 

[amends]

Update: Installed 15 feet of 3/16th beer line. Got my mini fridge all hooked up and sitting at 39 degrees F. I have the PSI at 14 and I'm getting all foam still.

I can tell it's foamy coming out of the beer line. It's not clear like it should be. I see a nice clear stream, then for a second or two tons of foam, then a nice clear stream, etc.

Although I did move the keg from the basement up to here, could have gotten shaken up a bit. I guess I should wait 24 hours and then try?

As a side note, managing 15 feet of beer line is troublesome.

 

[brewinginCO]

I'd wait 24 hours to let the keg settle and come to temperature.

Also are your beer lines chilled all the way to the tap? Tomorrow, check if only the first pour is foamy or all. You can measure the beer temp of the first and subsequent pours.

Lastly, you can use a Velcro strip to manage the coil of beer line.

 

[amends]

After another 30 minutes of settling it's pouring a bit more slowly, but I got a good pour at 14 PSI!

When I say good pour, I mean about 1 and a half inches of foam, which is way better than it was.

 

[rawlus]

Force carbing above serving pressure causes a lot of these threads.
Too short a serving line causes a lot of these threads.
Fiddling with pressure and venting on already carbed beer causes a lot of these threads.

It's supposed to take some time to be ready... Relax and take some time.... Over carbing your beer in two days at 30 saved you only perhaps 3 days and you ended up with a big problem to deal with... If you want to serve at 12, carb at 12... It will be carbed good in a week and perfect in 2 weeks.... Leave it, don't drop it to serve.... Extend your tap lines to add resistance if it's foaming, adjusting pressures and venting doesn't correct foaming or the root cause...

 

[brewinginCO]

After another 30 minutes of settling it's pouring a bit more slowly, but I got a good pour at 14 PSI!

When I say good pour, I mean about 1 and a half inches of foam, which is way better than it was.

Glad to hear it's settling down.

 

[Jupapabear]

Cheers!