Is 12 psi enough pressure to serve rootbeer that is pressurized to 35 psi?

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I want to bring several kegs of beer and a keg of rootbeer to family function in a few weeks. I have two check valves that come off the same regulator. I want to know if I can use 12 psi to serve both the beer and the soda even though the soda will be pressurized to 35 psi at the start.
 

IXIboneheadIXI

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not sure, but i do know i have read that your soda needs to go through like 30 or 40 feet of tubing after it leaves the keg to the point it comes out and goes in to the glass. from what i read if you dont do that it shoots out and bubbles everywhere, makes no logical sense to me at all but thats what i read
 

Dunerunner

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If you have force carbonated the root beer, you should be able to cool the keg and reduce the head pressure at the relief valve and move beer and root beer at the same serving pressure. Leaving the root beer at 35 PSI is not advisable.
 

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35 psi is pretty heavy… and I believe those check valves are only meant for liquid (from backing up into the regulator). If it was me, I would shut the root beer valve off and just serve; I would think if the 5 gal root beer keg goes pretty quick (24 hrs) and is chilled, you will not notice any carbonation loss in the product. Eventually, as the keg empties you will probably need to add some co2 at which point I would shut the beer valve off, repressurize the root beer (@35) and then shut that off… adjust your regulator to beer (depending on your reg it might purge) and reopen the beer valve. Cheers!
 

mjap52

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I want to bring several kegs of beer and a keg of rootbeer to family function in a few weeks. I have two check valves that come off the same regulator. I want to know if I can use 12 psi to serve both the beer and the soda even though the soda will be pressurized to 35 psi at the start.
It won't lose much in terms of carbonation over a short period of time, but of course, the more head space, the more carbonation will leave the root beer.

The proper way to do it, if you wanted to serve root beer over a long period of time in a keezer or something would be to balance your serving pressure with your hose length. I'm not positive what the actual measurements would be, but I serve at 12psi @ 8 feet. So you could probably do 30psi at 25 feet, assuming it's 3/8 tubing. It takes more pressure to push the liquid through the longer tubing, so you get less foam on the serving end.
 
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I just need to serve the rootbeer from this keg for a few hours. It will be chilled for several days and pressurized to 30-35 psi prior to pulling it from the keezer. I have 30 ft of beverage line to use for serving the beer.
 

david_42

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A few hours, you'll be fine. But the root beer will de-carbonate the entire time. Sodas mostly need to be served a t 35-40 psi or they go flat.

Watch out for backflow. I would release the pressure completely before connecting the 12 psi.
 

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Watch out for backflow. I would release the pressure completely before connecting the 12 psi.
This is good advice!!! We once hooked a heavily carbed hefe up to a multi-regulator setup for a club event and watched the beer start flowing back up towards the regulator seconds later, this was even after venting the keg. Luckily the gas lines were clear and we could see it happening and shut it off before it was too late.
 

cwi

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I just need to serve the rootbeer from this keg for a few hours. It will be chilled for several days and pressurized to 30-35 psi prior to pulling it from the keezer. I have 30 ft of beverage line to use for serving the beer.
I have some experience with highly carbed ciders and sodas. 30-35psi is going to be problematic. I max out at 25-28 psi for dispensing. For more vols of CO2 than that pressure will give, lower temps will result in more vols. Higher pressures than that are very problematic. Lower temps will help with things all around- keep it as cold as possible.

Depressurizing will work for short term serving, but, confusingly, the results will be better result if large(r) ID line (shorter length) is used. The problem is that while the serving pressure is only 3-12psi, the soda is still 30+psi. When it travels through the line, any obstruction causes a nucleation/cavitation site. The velocity of the fluid also exacerbates the situtation, and a smaller line will have a higher fluid velocity. This effect is amplified since the pressure in the line is less than the pressure in the soda.

Think of it like depressurizing a 2 liter bottle, then gently pouring into a glass, as opposed to pouring at the same flow rate through a straw with a bunch of spikey obstructions in it.

For long term serving, balancing the system is the only way to get reliable results. I have found that 3/16 id is about at the lower limit to get reasonable pour speed, and also keep the velocity down (which still affects things even when serving at carb pressure). Similarly, any obstructions in the line/path impact things much more than at lower pressures. Colder temperatures help tremendously here, too.

In the end, staying below the upper serving pressure limit of the system is more important than carb'ing to style. More carb will actually end up in the glass this way. I even tried using some true soda faucets I have that are very similar to the new Perlick flow control faucets, and it was still difficult to get good pours. When Perlick comes out with the SS version, I will be picking one up to try out.
 

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I have no problem at all serving soda at 30-35 psi through 30' of line (3/16" beer line). I've done it for years and years.

But if you have to turn off the gas to serve, you may have some foam. I'd try it and see before hauling it to a party. Just see if you can serve it at 12 psi for a few, and if it works out then you're all se.
 

cwi

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I have no problem at all serving soda at 30-35 psi through 30' of line (3/16" beer line). I've done it for years and years.

But if you have to turn off the gas to serve, you may have some foam. I'd try it and see before hauling it to a party. Just see if you can serve it at 12 psi for a few, and if it works out then you're all se.
I have had it work well sometimes, and be very problematic other times- depending on which keg, shank, faucet, line, QD, etc. combination was used. I am going to try switching to a barbed QD and see if that helps.

You may have had the magic setup. I believe you are using barrier line now. Are you still only using 30 feet of that at 30-35psi?

I still stick to the advice of using a shorter larger line when bleeding the pressure for short term serving. Run the lowest pressure to get the flow you need. If you have ever tried to dial in a jockey box, the issues are very similar. Some resort to bleeding pressure, instead of keeping the pressure at the proper setting, and everything chilled to appropriate temps.

Line restrictions and such can have a serious impact on foaming. I tracked down one foaming issue to using one of those flare-to-sanke coupler adapters on a shank. The inner shape of those things don't work as well when reversed.

My cider, and some root beers, have had more foaming issues than ginger ale. That may be part of my troubles as well. Although, based on the number of threads about trying to get sodas to serve properly, I think it is a pretty common problem
 

Dstreetbrew

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I cab my root beer at 25psi for a week and serve it weekly at a farmers market where I make root beer floats. I server it @ 10psi with about 4-5 feet of hose. Comes out perfect with a beautiful head. Hope that helps
 
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I tried carbing at 35 psi and then serving at 10 psi using 20 ft of 3/16 line and still got too much foam. I am going to reduce the pressure to 25 psi and try again.

Thanks for the advice everyone.
 

cwi

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I tried carbing at 35 psi and then serving at 10 psi using 20 ft of 3/16 line and still got too much foam. I am going to reduce the pressure to 25 psi and try again.

Thanks for the advice everyone.
I have made numerous attempts to do what you are trying. Using intermediate pressures is very problematic.


The best results come from either balancing the system for pressure dictated by the vols of CO2 and serving temperature; or, for short term only, by using a shorter, large(r) diameter serving hose, and reducing the pressure and shortening the hose until it does not foam. The shorter the hose, the better.

If you are not going to be able to reliably maintain the temps of the entire serving setup, reducing the pressure is much easier to manage. The pressure only needs to be high enough to just push the product. For long(ish) periods between serving, the pressure will need to be bled from the keg. The product will still stay close to the original carb level for a several hours even with the small losses to CO2 coming out of solution. Colder temps help minimize this effect.

A short, larger diameter hose will reduce foaming significantly. As I mentioned before, the shorter hose, the better. Going too much bigger in one jump than a smaller upstream orifice can sometimes cause cavitation/degassing issues, but 1/4" ID, and even 5/16" ID, seems to work OK for connecting to standard corny dip tubes and QDs.

At low pressures using short hoses, most issues are due to velocity. Just keep reducing the pressure of the reg, and bleeding the keg, to slow down the flow. If you still get foaming at too low flow rates, shorten the hose. If you still have issues, there is a cavitation/degassing site somewhere in the the line.

This approach is backed up by physics. It is no different than why you can pour soda from a bottle, or drink it using a short straw, without it foaming violently.
 

olie

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It takes more pressure to push the liquid through the longer tubing, so you get less foam on the serving end.
Just a minor nit: It takes more pressure to push liquid further uphill, but you can push liquid as far as you want horizontally with the same amount of pressure. This can be demonstrated with a simple (say, 100') garden hose siphon, or a 1000s-of-miles oil pipeline (granted, they use pumps for the uphill parts, but I assure you they aren't pressurizing those pipes to 1,000,000 psi to go the distance! :) )
 

olie

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It makes Zombie Thread very cranky when you wake it up from its five year slumber to pick its nits!
Well, Zombie thread will just have to get over itself, won't it... ;)

Ok, seriously: Wasn't trying to be picky, just wanted to augment the information available for future readers. "Teach your children well" and all that!

If Zombie thread is ever in town, I'll invite it over for some beer, perhaps that will assuage its crankiness. <G>
 
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