Carbonation Difference Between Kegs?

[LogicBomb]

Is it normal to have carbonation differences between kegs that are all fed from the same pressure/manifold?

My Co2 comes into a 4-way manifold at 12-14 PSI that feeds 4 kegs/4 taps.

I've attached a photo for quick reference.

Basically, it seems like the keg attached to "1", furthest from the Co2 inlet will always pour half a glass of foam, and then it progresses less up to the keg that is fed closest to the Co2 inlet marked "4" (which is apfelwein, actually). I seems like the closer to "4" I get, the more ideal the carb level is.

Could this be a result of the different types of beer, or are my kegs all getting different pressures?

I keep my keezer at 7.2C / 45F as measured with the probe submerged in water and allow for a 1C swing in temp (not sure what it works out to in F, 1.8F maybe?).

My beverage lines are 6 feet each.

 

[BeerGrylls]

Are these all force carbonated? How are you determining carbonation level, are you basing it on how much the beer is foaming? That could be due to many factors.

 

[LogicBomb]

All force carbed, yes.

Yes, basing it on how much my beer is foaming. Not sure how else I would measure it other than my Co2 Pressure dial, which reads 12-14 PSI (I forget which exactly it is).

They were fine for the first 2 weeks after carbing up, only suddenly in weeks 3-4 are they starting to get foamy.

 

[JuanMoore]

They could be seeing slightly different pressures if the check valves for each line have different cracking pressures. Not enough to really be noticeable though. The differences in the amount of foam between the different kegs is due to the differences in the beer. The higher the FG and the more protein in the beer, the more head it will have given the same carbonation and pour speed. Apfelwein typically has a very low FG and no protein, so even at very high carb levels it won't have much head at all.

The difference in foam over time is likely because at 1-2 weeks it hadn't fully reached equilibrium, and now at 3-4 weeks they're fully carbed.

The warmer a beer is, the slower the pour needs to be to prevent the CO2 from coming out of solution and causing excessive foam during the pour. At 45° and only 6' lines, I'm surprised the beers aren't pouring nearly all foam. I'd suggest dropping the temp a couple degrees and replacing the beer lines with at least 12' of 3/16" id if you want to reduce the amount of foam you're getting.

 

[LogicBomb]

Juan - I'll drop the temp tonight. Thanks! Would that mean I should also drop the PSI if I'm dropping temp?

I bought this kegging kit from OntarioBeerKegs and they came with:

6' of Bevlex 200 Beer Line (Thick wall 3/16" ID X 7/16" OD) for each tap

I didn't even question length since it's the same on every kit they send and just assumed it was a "good for most people" length.

 

[JuanMoore]

Juan - I'll drop the temp tonight. Thanks! Would that mean I should also drop the PSI if I'm dropping temp?

I bought this kegging kit from OntarioBeerKegs and they came with:

6' of Bevlex 200 Beer Line (Thick wall 3/16" ID X 7/16" OD) for each tap

I didn't even question length since it's the same on every kit they send and just assumed it was a "good for most people" length.

Yep, use a chart like this one to determine what pressure to set it at to maintain your desired carb level.

The kits all come with 4-6' of line because that's what the commercial line balancing calculators tell you is needed. The problem with the commercial line balancing calculators is that they're designed to result in a flow rate of ~1 gal/min, and assume commercial serving conditions, which is <38ºF and <2.7 vol of carbonation. If you're serving warmer or more highly carbed beer, you'll need a slower flow rate and much longer lines. If you don't mind cold beer and don't want to replace your lines, they'll probably work ok if you drop the temp below 40°F at your relatively low carb level. If you do replace the lines, go longer than you think you'll need. The only side effect of extra long lines is a slightly slower pour, and it's much easier to trim a off a few feet if it's too slow than it is to replace the lines yet again.

 

[zachattack]

I'll add that if you don't have a fan in the keezer, it's a good idea to install one. The kegs and lines could be at slightly different temperatures without one, and that could certainly contribute to the differences you're seeing.