Outdoor Dispensing, Jockey Box, Foam

[tspenard]

Hi,

I don't really know where to go for improvement on my outdoor trash can keg setup. Hopefully a description of my goal, system, and results can help this kind forum to suggest changes.

My goal is to dispense several kegs over the course of 5-7 days and not waste a bunch of beer via foam. The setup will be outside in 80-90*F weather.

What I have made is a heavily insulated round trash can with a 3/4" plywood surface/lid over top of that. There is heavy insulation on the bottom of the plywood that fits perfectly into an seals against the insulation glued into the trash can, so that when assembled the entire trashcan void is airtight and waterproof. A jockey box and CO2 tank sit on top of the plywood, each fixed in place. I made the jockey box such that the beer inlet passes through the bottom of the cooler. The beer shank has been waterproofed so it is insulated and leak-free. The faucet is mounted high on the front like any other jockey box. Inside is 50ft of 5/16"OD SS tubing.

To enable servicing of the trash can I used longer than ideal beer and CO2 lines. The line is about 8ft long so that the plywood and cooler assembly can be lifted off and placed nearby to get to the keg/coupler and add ice.

Unfortunately the results are pretty much nothing but foam. What happens is that the beer appears to pour out clear, cold, and at a good rate for about two ounces, then the beer in the glass starts to release it's carbonation at a staggeringly fast pace. The foam "blooms" up and out of the glass if you keep pouring.

Using the 1/4 full keg of Sam Adams Summer Ale from my kegorator (it poured fine there), I tried several diferent pressures and let the beer sit at each pressure to stabilize, but the best I could manage was about 1/2 glass foam. My starting target setting was about 30-35 psi what with the 50ft of 1/4"ID tubing creating backpressure. Somewhere between about 25-30 psi seemed to achieve the "best" result. Shortly after these initial checks and much wasted foam, the keg was emptied and I had to stop experimenting. I don't have much time left before this needs to go into use so I'm looking for silver bullets of knowledge as a last resort

I have several concerns about the setup, now that it has poven not to work. The thought was that a fully enclosed i.e. "refrigerated" beer system would not suffer the temperature variations found with conventional picnic tap, jockey box with outside beer line, or kegorators with warm tower. I figured the higher pressure needed to deliver through the extra coiling would balance out at the pour. If I had to vent the keg each night to keep the beer carbed properly then so be it. Clearly I'm missing at least one problem.

What if the keg temperature (sitting in ice water) is (let's say) 10*F colder than the air space where the 3/8" beer line is coiled. Could that temp rise cause this much gas in the clear line? Would then the trapped gas pass through the entire coil in gas state even thought the coils are close to 32*F? I had thought that the jockey box setup would redisolve CO2 into the beer because it is so cold throughout the coil.

The 3/8" beer feed line: it is pretty long and it coils randomly around the top area of the keg before pointing up a few inches to the jockey box coupler. Is this A) too large diameter of hose B) too long C) too many turns rather than going straight uphill? The beer shank that came with my DIY jockey box kit is 3/8" ID, another reason why I stuck with the 3/8" ID beer hose. Should I go to 1/4" to match the IDs of the SS coil and the faucet shank?

Servicing this currently designed setup is very bulky. I could make a service hole with insulated cap, and I could install much shorter beer hose with quick disconnects if that would help.

Any thoughts on venting keg pressure each night, or even more often, to alleviate overcarbonation?

Somewhat OT: why does lower CO2 pressure result in foam as well as higher pressure?

 

[Bobby_M]

You'll have better results if you just fill the garbage can up with ice to keep the keg cold. Add ice as necessary from a separate cooler. That way you can serve it with 10-12psi through 8' of 3/16" ID tubing.

If I understand your experimentation, you have the keg full of cold beer inside the container and you're hitting it with 30PSI to push it through all that tubing in the jockey box. The reason it's pouring foam is that you're beginning to overcarb the beer in the keg with that much pressure.

 

[tspenard]

You'll have better results if you just fill the garbage can up with ice to keep the keg cold. Add ice as necessary from a separate cooler. That way you can serve it with 10-12psi through 8' of 3/16" ID tubing.

Thank you for your reply.

The keg is covered in ice/water and the container is well insulated. Your 8ft of 3/16" tubing suggestion would work about the same way as a kegorator. That's fine, but I was hoping that all this talk about how great jockey boxes are, along with keeping the beer hoses inside a refrigerated space, would be even better, not horribly worse.

If I understand your experimentation, you have the keg full of cold beer inside the container and you're hitting it with 30PSI to push it through all that tubing in the jockey box. The reason it's pouring foam is that you're beginning to overcarb the beer in the keg with that much pressure.

How do all of the participants at craft beer festivals dispense all day in the hot weather using a keg, external lines, and jockey box? My foaming issue happened after a short settling period, not after sitting all day at 30psi. Whether they use a coil or coldplate, the pressure needs to be increased to balance the pour. Somehow everyone except me seems to be successful at using a jockey box.

 

[JRems]

I wouldnt use the large 3/8" jumper from the keg to the jockeybox. 1/4" should be fine if it's under 10'. Also why is your pressure so high?jockey box pours are usually much slower than a regular pour from a kegerator. I think you might be running too high psi. You should have a very slow pour. 50' of 5/16 tubing should be plenty to get the beer cold.

 

[tspenard]

I wouldnt use the large 3/8" jumper from the keg to the jockeybox. 1/4" should be fine if it's under 10'. Also why is your pressure so high?jockey box pours are usually much slower than a regular pour from a kegerator. I think you might be running too high psi. You should have a very slow pour. 50' of 5/16 tubing should be plenty to get the beer cold.

I'm not a beer expert but I've been reading about line balancing since buying a kegorator in 1996. To answer why my pressure was so high, every article I read about jockey boxes with 50+ feet of coil suggest somewhere between 25-35psi. The additional resistance of 50 extra feet of small ID piping required more pressure to deliver the beer at a given rate. I had thought the reason for this was twofold: get beer in the cup in a reasonable amount of time and create the correct (flowing) pressure drop at the tap so that CO2 stays primarily in solution.

I tried low pressure and it was worse. Nothing but foam right from the tap. Most articles and troubleshooting guides I've read indicate too low pressure can be a cause of foam. I don't understand it, but trust what I've read.

When the parts and new keg come in I'll try a 1/4" line as short as possible, limited only by accessibility of the cumbersome design. Hopefully it will go primarily upward from keg to cooler rather than dipping and wrapping around like a cobra.

 

[JRems]

Also, when the beer enters the cooler through the bottom shank, the top of the coil should be the attached to the bottom shank. The tubing coming from the bottom of the coil should go to the faucet. I'm thinking you have it hooked up backwards. You have to battle to push the beer up through the coil. If it hooked up the other way the beer has gravity working on it's side on the way through the coil. Also the bottom of the cooler is the coldest and that's where you want the beer to flow through last before it comes out the faucet.

 

[tspenard]

Also, when the beer enters the cooler through the bottom shank, the top of the coil should be the attached to the bottom shank. The tubing coming from the bottom of the coil should go to the faucet. I'm thinking you have it hooked up backwards. You have to battle to push the beer up through the coil. If it hooked up the other way the beer has gravity working on it's side on the way through the coil. Also the bottom of the cooler is the coldest and that's where you want the beer to flow through last before it comes out the faucet.

I know I'm asking for help here, but I disagree with both of these statements. I could be wrong.

You can't cheat physics and gravity in terms of filling the coil from one side verses the other. There will the same amount of rise and fall throughout the entire passageway no matter how it is hooked up.

Also the bottom of the cooler *may* be the coldest due to convection, but I would suspect that the middle to top area where the bulk of the ice is floating is actually the coldest spot. In fact think I saw a wire rack for sale that is designed to prop up a cold plate type cooler so that it sits above the liquid water portion of the cooler. I couldn't imagine any other purpose for it but the description was weak and so was the picture.