Idea for a different design of jockey box.

[Jeepaholic]

I have been wanting to build a Jockey box for a while but the cost of stainless tubing or a chill plate has kept me from it. The problem is that I want at least a 4 tap. I have seen designs that have 50 foot of tubing per tap. There is no way I can afford it.

Here is my plan. Make 4 short 10 feet long counter flow chillers. It would still have everything submerged in ice water in a cooler. A small 12 volt pump could run quite awhile on a power tool battery whitch I have plenty of. It would much more efficiently cool the beer.

Do you think it will work? Yes I know it will be a little more complicated but I think it's a good trade off.

 

[Jeepaholic]

I just realised I put this in the wrong forum. Can a moderater please move it to kegging?

 

[BeerGrylls]

I don't agree that using a pump and counterflow would give any appreciable gain. This is because the concept of counterflow chilling operates on heat exchange. The warmer liquid (beer) flows across the cooler liquid (ice water) and for the length of the contract area, the exchange occurs and the beer becomes colder (as the ice water heats up). So it's a function of 1. Time in contact 2. Temperature differential 3. Barrier material thermal conductivity 4. Circulation. In this case, a counterflow chiller isn't changing any of these except #4, versus just putting the coils directly into the ice bath. There are engineering equations you can use to determine how much heat exchange will occur, but I can't recite them. You'll need to know the ambient temp of your beer, the type of metal tubing, length, and diameter.

So the short form of what I'm saying is that it would be almost identical to placing the four 10' coils directly in the ice bath. I'm sorry to poo on your idea. It seems like a great idea at first blush, but it sounds like economy is of some importance here. I don't want to see you waste money time and effort just to find out it doesn't really do what you expected.

 

[millerjr934]

Why not just use vinyl tubing in place of stainless

 

[insanim8er]

Why not just use vinyl tubing in place of stainless

Rules of thermal transfer... The beer outside the cooler is warm and wouldn't pick up enough cold transfer during its short course through the jockey box.

 

[BeerGrylls]

Why not just use vinyl tubing in place of stainless

Again good thought, but you really need to pay attention to the thermal conductivities. It's typically measured in Watts per meter Kelvin. The reason why this works so well with steel is that it's around 16-20 W/mK. Copper is at least 350 w/mK. The higher the better, but at higher cost like anything else. The problem is that rubber, vinyl, and other polymers are usually around 0.5 or so. They are good insulators, so they don't conduct heat very well. You'd have to really compensate with length or contact area.

Then you start foaming the beer due to physical resistance...

 

[Jeepaholic]

I don't agree that using a pump and counterflow would give any appreciable gain. This is because the concept of counterflow chilling operates on heat exchange. The warmer liquid (beer) flows across the cooler liquid (ice water) and for the length of the contract area, the exchange occurs and the beer becomes colder (as the ice water heats up). So it's a function of 1. Time in contact 2. Temperature differential 3. Barrier material thermal conductivity 4. Circulation. In this case, a counterflow chiller isn't changing any of these except #4, versus just putting the coils directly into the ice bath. There are engineering equations you can use to determine how much heat exchange will occur, but I can't recite them. You'll need to know the ambient temp of your beer, the type of metal tubing, length, and diameter.

So the short form of what I'm saying is that it would be almost identical to placing the four 10' coils directly in the ice bath. I'm sorry to poo on your idea. It seems like a great idea at first blush, but it sounds like economy is of some importance here. I don't want to see you waste money time and effort just to find out it doesn't really do what you expected.

Good points. If I get time this weekend I may try some experiments with a couple of fountain pumps.