Jockey Box Cooling Mechanisms

HBT App users, please view this in a broswer so that you can answer the poll.

There seems to be a lot of misinformation floating around that the only effective jockey box is with coils. While coils are very effective they are also space hogs. Cold plates get a bad rap but are also extremely effective.

The goal of this poll is to get a cross section of the HBT community that uses jockey boxes. The ideal respondent has used both cold plate and ss coil jockey boxes in similar conditions. If you have only used one type of cooling mechanism please respond accordingly. If you have not used a jockey box personally please do not respond. I don't want to hear about what you "heard." That would just be hearsay.

Comments are definitely accepted but don't make this a debate. I want to use this thread/poll as a way to consolidate the experience of this community.

I would like to point out that there are a lot of variables that are not taken into account with this poll. You can post the environmental conditions in a post if you'd like. That would be helpful to the community. Key variables could be:

-keg temperature
-ambient temperature
-average pours in a 10-minute period
-number of (5 gallon or sixtels) kegs poured in one session.

If there is something else you think is important then please add it your post. I will update the important variables list if you guys think something else needs to be on the list.

Well I can't vote as I am only currently building my first jockey box, but I chose to go with a cold plate design. The key reasons for this were that I wanted a multi-tap rig (5-7 taps) and obviously coils would require a huge ice chest for this.

I have all of the parts in hand, including a 7-circuit cold plate. However I'm starting with only 2 taps (with space for another 3). I was going to pass each line through the cold plate twice since I'll have open circuits, however after calculating the system resistance with only 1 pass it has me thinking that 2 will not work.


sandyeggoxj, since it seems you have experience with cold plates would you mind helping me with resistance design decisions? Anyone else who can help is more than welcome to chime in. I know this may not be the best place for this, but it is REALLY hard to find good, reliable information (especially all in one place). Maybe there should be a cold plate sticky or something. For instance, I had a hard time (and am still unsure) finding the stainless tubing size and length of each circuit in the cold plate. This makes it a bit hard to calculate resistance properly. So in calculating my system's resistance, this is what I came up with:

- Gravity: 4 ft (rise) x 0.5 lb/ft = 2 lbs resistance
- Beer line (3/16" I.D. vinyl): 6 ft (5ft keg-plate, 1ft plate-tap) x 3 lb/ft = 18 lbs resistance
- Cold plate (1/4" O.D. SS): 12 ft x 1.2 lb/ft = 14.4 lbs resistance

2 + 18 + 15 = 35 lbs resistance.

This means I'll have to keep the regulator around that number to reduce foaming issues. This seems too high. Couldn't I replace my 3/16" beer line with 1/4" and thus reduce the restriction some? This would get it into the 5 lbs range (for just the beer line; 6ft x 0.85 lb/ft = 5.1 lbs), which would make my total system resistance around 21-22 lbs mark. This seems more manageable. Are there any reasons why I wouldn't want to do this? All I see is people using 3/16" line on cold plate jockey boxes, but I'm not sure why.

Thanks for any help!

I use 5/16 liquid line from the kegs to the cold plate. If I double pass the jumper is 5/16 as well. Most cold plates are 1/4" id tubing. I run 3/16" from the exit of the cold plate to the shank. Turn it up to about 15 psi and off you go. Don't worry about the resistence too much. Since the kegs will only be on the jockey box for a short period of time it is okay not to have enough co2 pressure to maintain carbonation. I like to dial in my regulator to hit a flow rate off the faucet that meets my needs.

I'm not worried about maintaining the carbination level of the beer (which is going to be 2.5 vols). They will already be carbed for several weeks prior to hooking them up. I plan to serve them Mardi Gras day on the parade route, so we start drinking early (6am) and finish by around 4pm. Thus, I'm not worried about them over/under carbing in that amount of time.

But in order to get correct serving pressure you have to balance your system. I don't understand how you can just say "don't worry about the resistance". I know the calculations are just giving an estimate, but that's the whole reason we have and use them. Check out this manual from Perlick for a really awesome breakdown of system balancing. I've only used picnic taps until now so I haven't had to worry about this until now, but it still seems pretty imperative to me even in my noob state.

Don't you find that when you double pass, adding the extra 12 ft through the cold plate should make you need to dial it up an additional 10-15 psi?

sandyeggoxj said:

I use 5/16 liquid line from the kegs to the cold plate. If I double pass the jumper is 5/16 as well. Most cold plates are 1/4" id tubing. I run 3/16" from the exit of the cold plate to the shank. Turn it up to about 15 psi and off you go. Don't worry about the resistance too much. Since the kegs will only be on the jockey box for a short period of time it is okay not to have enough co2 pressure to maintain carbonation. I like to dial in my regulator to hit a flow rate off the faucet that meets my needs.

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This is what I do. I have about 6' of 5/16"ID beverage line from the keg to the cold plate. There is 12' of 1/4"ID SS line in the cold plate. Then a 1' jumper of 5/16"ID beverage line to the next cold plate followed by another 12' of 1/4"ID SS line through that cold plate. And then finally about 18" of 3/16"ID beverage line to the faucet shank. I run the regulator at about 15psi, give or take, and it works great. The beer is nice and cold and does not foam excessively. Those are my settings. I have used this in ambient temps of 70-85 degrees and kegs that are approximately 70 degrees. If the beer is any colder it will start freezing.

Inside the jockey box I have the cold plates resting directly on block ice and then I fill the rest with cubed ice. I have a 1/4 turn ball valve on the drain connected to a short hose. When I am inside this constantly drains into a small bucket and outside I just let it drain to the ground. This keeps the cold plates away from the liquid. I can serve 25 gallons at a rate of 15 pints/10 minutes without running out of ice or serving warm beer. It could probably pour faster than that but I haven't been in a situation where I needed to be pouring so fast.

I made one based on the one in the video below, but with some changes. It works well for my needs.

Anyone else have input on their experiences? I know there are more jockey boxes floating around here...

sandyeggoxj said:

I have used this in ambient temps of 70-85 degrees and kegs that are approximately 70 degrees. If the beer is any colder it will start freezing.

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Thanks for posting your setup info. Ideally this is exactly what I want my jockey box for - to serve room temp (~70*F) kegs. I've read in multiple places though that the kegs need to be kept at least chilled somewhat (under 50 or so). I've never heard of the beer freezing. But you're one of the few people who I've heard can pull this off, so kudos, your setup must be working for a reason.

It's just the numbers that throw me off. Maybe I am worrying too much like you said. But each pass through 12' of 1/4" SS tubing is equal to about 14.4 lbs of resistance (1.2lbs/ft). If you double pass, that's 29lbs needed, not counting any other beer line or gravity. The fact that you're only pushing half of that is strange, but I'd rather push less anyway (save some CO2), so perhaps I should try setting things up just like you.

Just wondering, do you have the kegs situated under, over, or level with the jockey box when serving?

I've used both extensively. Cold plates can cool 80F kegs if they are double passed. Unless the keg is cold a single pass won't get it done. A single pass through a coil will get it done, but as you said Sandy, they are space hogs. You can get 2 4 pass cold plates and double pass each and have a 4 tapper jockey box, but you'll never get more then 2 coils in the same cooler.

I have seen the compression fittings on the coils leak, though I suppose that could happen with the hoses/clamps on a cold plate as well.

Both work, but for more taps per cubic inch of space, Cold plates get it done. If you only need a 2 tap jockey box, I'd probably opt for 2 coils.

Only actual jockey boxes I've used were cold plates, and they worked fine. I did use the copper HEX coil from my brew system as a makeshift jockey box for a party once, and it worked fine too. They both have their pros and cons, but IMO either is a valid option.

MagicMatt said:

- Gravity: 4 ft (rise) x 0.5 lb/ft = 2 lbs resistance
- Beer line (3/16" I.D. vinyl): 6 ft (5ft keg-plate, 1ft plate-tap) x 3 lb/ft = 18 lbs resistance
- Cold plate (1/4" O.D. SS): 12 ft x 1.2 lb/ft = 14.4 lbs resistance

2 + 18 + 15 = 35 lbs resistance.

This means I'll have to keep the regulator around that number to reduce foaming issues. This seems too high. Couldn't I replace my 3/16" beer line with 1/4" and thus reduce the restriction some? This would get it into the 5 lbs range (for just the beer line; 6ft x 0.85 lb/ft = 5.1 lbs), which would make my total system resistance around 21-22 lbs mark. This seems more manageable. Are there any reasons why I wouldn't want to do this? All I see is people using 3/16" line on cold plate jockey boxes, but I'm not sure why.

Thanks for any help!

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MagicMatt said:

But in order to get correct serving pressure you have to balance your system. I don't understand how you can just say "don't worry about the resistance". I know the calculations are just giving an estimate, but that's the whole reason we have and use them. Check out this manual from Perlick for a really awesome breakdown of system balancing. I've only used picnic taps until now so I haven't had to worry about this until now, but it still seems pretty imperative to me even in my noob state.

Don't you find that when you double pass, adding the extra 12 ft through the cold plate should make you need to dial it up an additional 10-15 psi?

Click to expand...

MagicMatt said:

Thanks for posting your setup info. Ideally this is exactly what I want my jockey box for - to serve room temp (~70*F) kegs. I've read in multiple places though that the kegs need to be kept at least chilled somewhat (under 50 or so). I've never heard of the beer freezing. But you're one of the few people who I've heard can pull this off, so kudos, your setup must be working for a reason.

It's just the numbers that throw me off. Maybe I am worrying too much like you said. But each pass through 12' of 1/4" SS tubing is equal to about 14.4 lbs of resistance (1.2lbs/ft). If you double pass, that's 29lbs needed, not counting any other beer line or gravity. The fact that you're only pushing half of that is strange, but I'd rather push less anyway (save some CO2), so perhaps I should try setting things up just like you.

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I hate all of the misleading information on the web regarding "balancing" draft beer systems. The vast majority of it completely ignores basic laws of fluid mechanics and makes assumptions that often don't apply to homebrewers and home-draft users. The first misconception might stem from the phrase "line balancing". This implies that there's some magic balance between pressure and resistance that results in a good pour, and anything else will cause foam. This couldn't be further from the truth.

The reason resistance is required in a draft system is to slow the flow of beer down until it's gentle enough that the CO2 doesn't get knocked out of solution and result in a ton of foam as it makes it from the faucet to the glass. How slow and gentle the pour needs to be to accomplish this is highly dependent on the serving temperature and carbonation level of the beer. The warmer or more highly carbed the beer is, the slower and gentler the pour needs to be.

For commercial systems where the beer is stored between 33° and 36° and the carbonation level is between 2.5 and 2.7 vol, people have found that the fastest a beer can be poured without excessive foam is ~1 gal/min. All of the equations,resistance figures, calculators, and most of the articles you've likely found assume this flow rate. There are a couple problems with this assumption. First, if you use those equations and resistance figures you'll end up with a flow rate of 1 gal/min, which in many cases is too fast and will result in a firehose of foam. The second is that line resistance is not a constant for a given type of beer line, it's dependent on the flow rate. This means that those figures and equations are completely useless for any flow rate other than 1 gal/min.

The other common misconception is that extra long lines, or additional resistance beyond the "ideal" or "balanced" figures will cause some sort of problems or foaming. There are only two side effects of extra long lines, a very slightly slower pour, and the ability to serve beer at a much wider variety of temperatures and carb levels without any issues. Since line resistance decreases exponentially as flowrate decreases, doubling your beer line length barely has a noticeable impact on how long it takes to fill a pint.

Most of what I've typed above is more applicable to traditional permanent serving systems. Getting enough resistance in those cases is imperative, as the serving pressure can't be changed without affecting the carbonation levels. The beauty of a temporary jockey box set-up is that you really don't need to worry about having the resistance dialed in, because you can simply turn the pressure down at the regulator to drop the flow rate. Since the beer will only be at that pressure for less than a day, there's not enough time for the carbonation levels to change very much.

One additional misconception you seem to have is that you set your regulator pressure based on the expected line resistance, which is never how it should be done. For permanent beer serving you should set your pressure based on the beer temperature and carbonation level, using a chart like this: http://www.kegerators.com/carbonation-table.php For jockey box set-ups, doing the same thing is a decent starting point. If it flows faster than desired or you're getting foamy pours after the kegs have had time to settle, you can turn the pressure down to slow the flow.

That's probably more than you wanted to know, but I hate seeing people being led down the wrong path by that "awesome" manual by Perlick. It actually can be a very useful manual for commercial systems, but you have to know it's inherent limitations. If you like to keep your beer really cold and at moderate carb levels no matter what, then go ahead and use it. Just realize that the "ideal" and "balanced" result it gives you is the fastest a beer under those conditions can be poured without excessive foam (very important to a bar selling beer to pay the bills, but not a worry for me). If I have time to drink a beer, then I also have an extra two seconds to wait for it to pour, and those two seconds are well worth the added flexibility my system has in terms of serving temperature and carbonation level. That's just me though, YMMV.

TLDR version:
No, you don't need to turn the pressure up to compensate for the additional resistance from a second pass. The only effect of adding a second pass is colder beer flowing ever so slightly slower, both of which help reduce the chances of excessive foaming.

And no, you don't turn your regulator up to match some flawed resistance figure you've calculated to prevent foam. That's actually highly likely to cause foaming.

It's not too much info at all. Your post should be a sticky lol. I'm like a sponge, and appreciate all input!

I just want to make clear that I'm aware of how generally you start with the carb level and temp of the keg and work out the resistance to match that number for permanent setups. I was specifically referring to jockey boxes. Since the line length is mostly fixed (i.e. inside the cold plate), there isn't much I can do other than keep the resistance as low as possible with a larger diameter beer line, similar to what Sandy is doing.

How does the temp of the keg have effect on the rig? IOW, will a room-temp keg require longer line/more resistance than a cold keg? Could this be the real reason that pushing 15psi through a double pass is doable? Wouldn't the carb level at that temp (2.5 vol) be somewhere around 30psi? So you would need at least enough resistance/length to avoid that much carbonation coming out of solution (which I'm thinking the double pass is likely doing dual duties in this case - chilling the beer to appropriate temp and adding extra resistance)?


I think I'm going to need to do some testing for sure. Maybe a dry run with some Coors or something cheap. Not that I'd ever put that stuff to my lips.

Sandy, was there any specific reason you put the 3/16" line to the faucet instead of 5/16"? Or just a preference? Sorry for all of the questions but thanks a lot! I'm trying to learn from previous mistakes so I don't waste time making them myself!

MagicMatt said:

Since the line length is mostly fixed (i.e. inside the cold plate), there isn't much I can do other than keep the resistance as low as possible with a larger diameter beer line, similar to what Sandy is doing.

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As I said, line resistance decreases exponentially as flow rate decreases. This means there's zero need to try minimizing resistance. If anything, you're more likely to need to increase resistance, not decrease it. I have a 35' long 3/16" id beer line in my keezer for the rare occasion I want to serve a soda. It's usually being used for beer at 12psi, and while the pour is certainly slower than my other lines, it's not painfully slow, and the extra length/resistance doesn't have any other ill effects.

MagicMatt said:

IOW, will a room-temp keg require longer line/more resistance than a cold keg?

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Yes and no. Assuming the flow rate and beer temp at exit is the same, the pour will be the same. Unlike permanent systems you don't have to match the pressure to the carbonation with jockey boxes, so you can set the pressure to result in your desired flow rate no matter what the keg temp is. If you want to stay as close as possible to the equilibrium pressure with the carbonation though (a good idea IMO), then a warmer beer will be at a higher pressure, which will need longer lines to achieve the same flow rate.

MagicMatt said:

Could this be the real reason that pushing 15psi through a double pass is doable? Wouldn't the carb level at that temp (2.5 vol) be somewhere around 30psi? So you would need at least enough resistance/length to avoid that much carbonation coming out of solution (which I'm thinking the double pass is likely doing dual duties in this case - chilling the beer to appropriate temp and adding extra resistance)?

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That first question confuses me, not sure what real reason you're referring to. Pushing 15 psi through a double pass is doable because it's a very low pressure (which means a slow/gentle pour) and the second pass adds resistance (even slower pour) and chills the beer further, all of which pretty much eliminates the chances of foaming.

Yes, room temp and 2.5 vol equals an equilibrium pressure around 30 psi. To get a decent pour at that pressure you need cold beer at exit and quite a lot of resistance, which once again would be aided by multiple passes. As long as the set-up isn't sitting regularly for longer than ~20 min between pours, you can get away with just turning the pressure down to slow the flow though.

MagicMatt said:

Sandy, was there any specific reason you put the 3/16" line to the faucet instead of 5/16"? Or just a preference? Sorry for all of the questions but thanks a lot! I'm trying to learn from previous mistakes so I don't waste time making them myself!

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I can't speak for Sandy, but a section of 3/16" line leading to the shank in a system with otherwise larger ID line is called a choker, and is typically used to increase resistance to get the flow slow enough.

Mind blown. I feel like everything I've learned is a lie! But I definitely get what you're saying. Mostly.... But thanks so much for helping me grasp all of this! This is exactly what I needed! And apologies to Sandy for putting a speedbump in the thread, but hopefully others out there can learn a thing or two as well!

JuanMoore said:

Yes, room temp and 2.5 vol equals an equilibrium pressure around 30 psi. To get a decent pour at that pressure you need cold beer at exit and quite a lot of resistance.

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So even after adding enough resistance you'd still need the beer to be cold at exit? What role the the temp play in this respect?

JuanMoore said:

As long as the set-up isn't sitting regularly for longer than ~20 min between pours, you can get away with just turning the pressure down to slow the flow though.

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What would the negative effect of this happening (sitting >20 min between pours) be?

MagicMatt said:

So even after adding enough resistance you'd still need the beer to be cold at exit? What role the the temp play in this respect?

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The warmer or more highly carbed a beer is, the slower and gentler the pour needs to be to prevent the CO2 from breaking out of solution and causing foam.

And few degrees makes a big difference. If you read through the plethora of "help, my beer is all foam" threads here, you'll notice that many people suggest a serving temp of 40° and using 10-12' lines. The 5' lines that come with kegerators and kits work just fine under commercial conditions of 33-36°, but the lines need to be doubled when the serving temp rises just 4°.

It's not that you need the beer to be cold for your jockey box to work, just that the warmer the beer is the more resistance you'll need to get a good pour.

MagicMatt said:

What would the negative effect of this happening (sitting >20 min between pours) be?

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If your serving pressure is significantly lower than the equilibrium pressure, over time CO2 will want to break out of solution in the line forming pockets of gas. If it sits too long between pours, the first pour after sitting will sputter a little and have a lot of foam. Not really a big deal, and usually a jockey box is being used frequently enough that it's not an issue. If you have enough resistance that you can keep the pressure at equilibrium (~30 psi for room temp and 2.5 vol) then you don't have to worry about it.

Good morning from the windier than normal old pueblo. Looks like you guys have been busy.

Matt,
I use the 3/16 at the end for two reasons. A choke point and also that is the size of the tailpiece barb for my shanks. It works well. It does pour a bit slower, but not bad.

I have some 120' SS coils waiting to go into a smaller 2 tap box one of these days. Those have the last ~15' in a small diameter tubing. There are compression fittings at both ends of the SS coil which could both pose a problem. The cold plates I have are made by micromatic and they use a flare nut with a nylon washer to connect to the plate and have a barb to connect to the hose. I use hose clamps for the 5/16"ID hose but the 3/16"ID hose just pushes on.

The first time that I used my jockey box was at my wedding last summer. That is why I built it. It was crazy how much people wanted to rent one for a few days so I just paid a bit extra and made one for myself. When I was trying to plan it I kept running into conflicting information. I ended up basing most of my design on the experience of a brewer in northern arizona. He told me how they set theirs up and I copied it.

Like a lot of things around brewing it is easy to get carried away trying to research something into perfection. I'd recommend just playing around with your jockey box and learning things first hand. Theory will only get you so far.

So I finally used my cold plate jockey box yesterday. I went with 5ft of 1/4" beer line from keg to cold plate, double passed with about 1ft of 3/16", and then used about 16" of 3/16" from cold plate to shank.

It worked great! I turned the temp down to 35°F on my keezer the night before, and pulled the kegs from it about 2 hours prior to tapping. Luckily it was pretty chilly out, so the kegs didn't get above 48°F before running dry. I taped a digital thermometer probe to one of the kegs near the bottom to monitor the temp and thus adjust the pressure accordingly so as to not overcarb the beer.I started around 12psi and increased to about 17psi over a few hours. In hindsight, I didn't need to worry about the keg pressure since the beer was gone within a couple hours (i.e. no chance to over - or under- carb). Next time if I'm sure the keg will be emptied within a few hours I'll just set it to about 15psi as per Sandy's suggestion and let it go like that until gone.

Anyway, thanks for all of the help and advice Juan and Sandy!

And on that note, I have a final question for you jockey box owners:

How do you store your box? Specifically with regards to flushing the lines....


I just now ran BLC and then Starsan through the lines, then blew as much as I could out with CO2. Is this sufficient? I don't want any mold or anything. I was going to leave the Starsan in the lines and not blow it out, but I was worried about it affecting the SS tubing within the cold plate over time. I probably won't use this thing again for another 2 months. That seems a bit long to leave starsan in the lines.

So how do y'all do it?

Glad it worked for you! For a single day I wouldn't bother changing the pressure. You won't change the carb volume any measurable amount in part of a day.

I have blown out the lines and I have left them with starsan. Depends on storage temp and time. It doesn't freeze here so no worries. But if you are in the north then dry lines! And time should be self explanatory.