Keg Line Length?

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lpdean

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I am putting together my kegerator and remembered reading something about the length of beer line from keg to faucet. I can't remember where i saw it but, it said something about the line needing to be at least five feet long to cut down on foaming. Wondered if anyone knew if there was truth to this or to just make the lines as long as needed. On the same note what about the length of the CO2 lines?
 
On the other hand, 10 feet of 3/16" and you'll be able to pour anything without foaming. That's how I set up my kegger. Slower pours on the low pressure ales, but what's an extra 10 seconds?

CO2 lines, doesn't matter. Long enough to reach, short enough to be out of the way.

And don't forget the check valve(s) to protect the regulator from backflow.
 
I finally find a page for my problem, and it's a dead link. Bump for new link/ information from page.
 
i recently swapped out my 1/4 line for 10' of 3/16. it pours perfectly. with the glass close the faucet it makes no foam, pull it away and it creates a nice head.
 
I'm using about three feet of tube and two of the "swizzle sticks" mentioned in the sticky post at the top of this sub-forum. My CO2 regulator is set to 12PSI and after two weeks, it was a perfect pour.

I think that's the sweet spot for me.
 
On the other hand, 10 feet of 3/16" and you'll be able to pour anything without foaming. That's how I set up my kegger. Slower pours on the low pressure ales, but what's an extra 10 seconds?

CO2 lines, doesn't matter. Long enough to reach, short enough to be out of the way.

And don't forget the check valve(s) to protect the regulator from backflow.

Quoted for truth. :mug:
 
10' of beer line is way to long for a typical direct draw system. If you use the formula's you will find it should be between 4.5 and 5" for the typical beer. The exception to this would be if you were using a highly carbonated beer. It would have to be 20 to 20PSI to use 10' unless you have a large difference in height? We get a lot of customers who read these postings and think they need much more beer line than they do. If I put 10' of beer line on a direct draw system in a bar they would kick me out of the place. 5 feet is more than enough of 3/16 line in the typical direct draw system serving at 38 degrees. In the vast majority of cases when a customer calls for help with a system that has foam we find the foam is due to temperature of the beer (about 80% of the time) or carbonation level (the beer was over carbonated by accident) and then they attempted to just serve push beer out at a lower level. I have had customers that were serving certain styles at 20+ PSI that definitely needed longer lines, but this is very rare. I believe that in most cases people using 10' of beer line are using way more beer line than they need. My opinion...for what it is worth.
 
I have 5 foot 3/16" lines and without some kind of restriction (e.g. the epoxy mixer sticks in the dip tube technique), I cannot pour @ 10-12 PSI, 40 F without getting a large amount of foam -- unless that tap has poured several beers in several minutes and is very cold.

I think this is a large part of the problem for homebrewers and the main difference between us and a commercial setup. A bar either has a glycol system cooling the taps, or they are pouring so often that they stay cold. We homebrewers, on the other hand, often pour through a warm tap, which can give you an inch or two of foam before the rest of the head builds.

Thus lengthening our lines or adding restriction, and slowing down the flow even more, allows for less foaming through a warm tap.

That's my $.02 on it based on a few years of homebrew kegging experience.
 
IMO, the length of beer line you need is dependent on the pressure that provides equilibrium in the keg and the height difference from the keg to the tap. The process is very straightforward. Set the PSI to the appropriate pressure that maintains the level of carbonation you want for the beer at its serving temperature (i.e. the regulator is never set to "serving" pressure and has nothing to do with serving). Then cut a length of beer line that adequately "consumes" the pressure at the regulator. 0.5 PSI is lost per foot that the center of the keg is below the tap. 0.5 PSI is gained per foot that the center of the keg is above the tap. And about 2 PSI per foot is lost with 3/16" inside diameter vinyl beer line. Whatever PSI you have at the regulator, just have enough beer line to get it to 0 at the tap. That balances your system.

On my system, the center of the keg is 2 feet below the tap. Most of my beers are set at 8 PSI (they are at 38F and I want 2.2 volumes of CO2). So I have to "consume" 8 PSI. since my tap is 2 feet above the keg, gravity takes care of 1 PSI (2 * 0.5 PSI = 1 PSI), and I have 3.5 feet of beer line to handle the rest (3.5 * 2 PSI = 7 PSI). That gets me a flow rate of about 2 oz/sec or 1 gal/sec.

Oh and this assumes you properly cool the beer lines as well. If the beer in the line is warmer, then you'll still have foam. So a way to fix that might be to lengthen the lines more to slow the rate of the pour.
 
The calculations are based on what pressure you think you want to use. Often times people are picking line lengths before they've ever pulled a single pint of their own draft.
Therefore, they really have no idea what temp they want to pour at.

It also assumes you'll be carbing to the same volumes of CO2 for eternity and that's not what we do in practice.

When someone says 10' is "too long" it suggests that there is a major detriment/con to it. The ONLY con to 10' lines is that you might never have to deal with a half glass of foam, ever. Cost? Maybe a $1.50 lost. Slow pour maybe? If you can't wait an extra 3 seconds for a pint you might want to reconsider having beer on tap.

Longer lines make up for perhaps wanting to pour warmer later (requires higher pressure). It allows for higher carbonation levels if necessary. It stops you from having to rebuy new line after finding out that you screwed up the pressure drop calculations.
 
I agree with Bobby....I had my 5' lines from KegConnection, (I love you guys, but damn those lines are too short). I know my beer was correctly carbed, I know my temp was right, (38F, verified by a NIST traceable hygrometer), and my taps are level with the tops of my kegs, 11 PSI pushing, lines all inside the fridge, so cold. 5' of line is WAY too fast. 10' of line works great. Around 6-8 seconds/pint, (big guess, I'm at work right now, can't actually test), and about 3/4" of foam at the top. Perfect.

Also, I don't believe commercial keg setups know all either....damn near every bar I see pours foam down the outside of the glass to get a good full pint in the glass...
 
I think this is a large part of the problem for homebrewers and the main difference between us and a commercial setup. A bar either has a glycol system cooling the taps, or they are pouring so often that they stay cold. We homebrewers, on the other hand, often pour through a warm tap, which can give you an inch or two of foam before the rest of the head builds.

Thus lengthening our lines or adding restriction, and slowing down the flow even more, allows for less foaming through a warm tap.

That's my $.02 on it based on a few years of homebrew kegging experience.

This is a really good theory. I think comparing beer line length from commercial to home setups is apples v oranges.
 
The calculations are based on what pressure you think you want to use. Often times people are picking line lengths before they've ever pulled a single pint of their own draft.
Therefore, they really have no idea what temp they want to pour at.

It also assumes you'll be carbing to the same volumes of CO2 for eternity and that's not what we do in practice.

When someone says 10' is "too long" it suggests that there is a major detriment/con to it. The ONLY con to 10' lines is that you might never have to deal with a half glass of foam, ever. Cost? Maybe a $1.50 lost. Slow pour maybe? If you can't wait an extra 3 seconds for a pint you might want to reconsider having beer on tap.

Longer lines make up for perhaps wanting to pour warmer later (requires higher pressure). It allows for higher carbonation levels if necessary. It stops you from having to rebuy new line after finding out that you screwed up the pressure drop calculations.

I'm all for 10' lines as the standard for a dynamic system (i.e. different carbonation levels, temperatures and so on). The worst thing that could happen then is a slow pour. I can wait 15 seconds if I have to. I'm just saying that, in theory, line length and not regulator pressure should control the flow rate of the pour. And that most folks' foam issues either have to do with line length (too short) or warmer beer in the lines. They can both be fixed by using longer lines. But more importantly, the warmer beer *should* be fixed by cooling the tower properly.
 
I disagree. Im in agreement with KegConnections. And Micromatic's Beer Serving Institute would agree, as I know several people who have taken the course.

3/16" beer line provides 3lbs of resistence per foot. 'Most' people carbonate their beer at 12psi. To have a balanced system, that means 4-5' of beer line. Why buy more if you dont have to??? But overkill is popular in this hobby.
 
Shop that noise to the hundreds of posters here who can't pour less than 3/4 a pint of foam on their 4 foot lines. The proof is in the pour and not a formula. 10 feet is on the extreme end for sure but the tubing is so dirt cheap that it's a perfect place to start. If you can't pour fast enough to get a decent head at the end of a pour, cut a foot off. Boo hoo, 30 cents wasted and everything.
 
4' lines worked for me @ 37F with 8 psi, but I was always doing a dance to keep the foam from happening.

I now keep my beer @ 45F with 13-14psi and find that 10' lines work great. I could probably lop off a foot or two and be ok, but why bother as it gives me flexibility.
 
The only harm in longer lines is slower pour and what to do with the extra slack... no other harm that i have seen... it sort of surprises me that the companies that make the "kits" don't just start with 10' lines - i bet their customer service calls would be far less as a result (instead of dealing with the checklist of foam issues) and you wouldn't get people complaining their foamless pour is too slow - they'd just cut off more line if they needed to.

what the longer lines does for alot of people i think is make the temp/height/tap balancing act much less of an impact on the quality of the pour - it adds a level of consistency and insurance that can make up for alot of things. which means less fiddling to get things right and an overall quicker and more pleasant experience.
 
I noticed the last comment about companies using longer lines. 10' of beer line is much more than is needed in the vast majority of sytems. As the owner of a draft beer company I believe it is important to determine the correct restriction length and then use that length on a system. For a standard, typical direct draw system 5' of beer line is more that you need. Putting 10' on will slow down the pour and offers no advantage unless you are serving an extremely highly carbonated beer. If you are getting foam at 12PSI with beer carbonated to serve between 10 and 14PSI your issue is with something other than hose length. It is due to temperature or the beer was carbonated to a rate higher than 12PSI equivalent (due to mistake) If you are serving your beer at 18PSI, you would need longer hose, but it would still not be 10', it would be 6' or 7'. I recently had a customer email me after reading suggestions on Homebrew talk saying his beer line should be 10' long asking why were were being "Cheap" and not installing longer beer lines. My first reaction was to start using longer beer lines, but I know that 10' is way to long and 95% of our customers have great results using 5' beer lines. I think changing the length would have negative results for many customers, including longer pour time, too much beer line to deal with in small spaces and increased cost for something that will give no benefit. We are always happy to put on whatever beer length you desire. Just call us and we will make the change for you. I just don't believe "more is better" is the correct philosophy. I believe it is better to get the correct length and use that.
 
what the longer lines does for alot of people i think is make the temp/height/tap balancing act much less of an impact on the quality of the pour - it adds a level of consistency and insurance that can make up for alot of things. which means less fiddling to get things right and an overall quicker and more pleasant experience.

I like this simple summary. I'm building a keezer right now, just getting into kegging and this whole beer line length/size foam issue is confusing. I need a simple solution that is basically a one size fits all. If my biggest drawback to 10' lines is a slower pour, I'm sold. I don't have the time/patience/knowledge to be messing with all the other variables.
 
I like this simple summary. I'm building a keezer right now, just getting into kegging and this whole beer line length/size foam issue is confusing. I need a simple solution that is basically a one size fits all. If my biggest drawback to 10' lines is a slower pour, I'm sold. I don't have the time/patience/knowledge to be messing with all the other variables.

I agree to a point. The only thing I really think those that keg should absolutely know is that the pressure set at the regulator should have absolutely nothing to do with serving. It's strictly the pressure at which the beer will be properly carbonated at its temperature. From there, we're only using the lines and height difference of the keg and tap to resist the pressure so that we don't have a fast pour that produces foam. A 10' line will surely do that. But if the lines are kept at the same temperature as the rest of the beer, then much shorter lines (5' or even less) can be used without problems.

I make my calculations for hose length, add a foot (or round up) and go from there. Actually, someone (don't remember who) once said that the flow rate should vary as the pressure does, meaning that highly carbonated beers should pour slower than lower carbonated beers. Which makes sense. But most calculations on pressure reduction in hose assume a 1 gal/min flow rate (about 6 seconds for a pint).
 
According to physics, 5' is about right for a 1 gal/min pour rate with those specs!

What physics? You're using an empirical formula, not one based in physics. If you were using physics, (really fluid dynamics), you'd need a LOT more information, (wall smoothness, is the line coiled or not, how tight is the coil, where and how many restrictions, turbulence inducing points, etc are there?).

I said this in another post, it seems Todd and I disagree. Some say 5' of line works, some say 10' of line works. All I know is that if 5' of line ISN'T working, you should try 10' of line. There's no "right way" to do this, just figure out how to pour your beer, whatever it takes.
 
Ok, keep it civil. You know damn well I'm not leaning on my post count as some kind of authority and I never have. What it means is that I spend a lot of time trying to help people.

Certainly faucet height does play a part. If you use a tower on top of your kegerator, you're already about 16" higher than faucets on a freezer collar or say in the front door of an old fridge. With towers, sure, shave 2 feet off that recommended 10' of line to start with.

My, and others, recommendation to start with 10 feet of line per is perfectly logical and I'll continue to defend it until you can show me how the pros/cons are outweighed against an "ideal" length. Let's work it out.

Lines that are "too long".
Pros: Just about foolproof way to resist overfoaming. Allows for warmer serving if you want to. Allows for serving of Wits and Belgians at over 3 volumes.
Cons: Costs about $1.50 more per faucet, May slow the pour down to an unacceptable speed, not enough head creation.
Fixes for Cons: Trim a foot and try again (waste about 30 cents every time you do that).

Lines that are "Too Short"
Pros: none unless you hate carbonation.
Cons: Glass full of foam. Have to come post on HBT about that problem. Have to buy new lines, even if they're only 2 feet longer than the ones you had. Essentially you waste the cost of the entire length of your original lines.

Lines that are "just right". You've done your calculations and in order to impress your draft beer profession friends, you got the 5.5' line that pours a 12psi beer just right.

pros: You can pour that 12psi beer just right, 2 finger head, as fast as possible.
cons: you can pour that 12psi beer just right, Grab some new line for a wit or mild. You decide your 38F set temp is too cold for your tastes so you raise it to 44F and now need to bump your pressure up. Now perfect is not.

Would it make everyone happy if I suggest starting with 9 feet instead? Done. Everyone with collared freezers,start with 9 feet and shave as necessary. Everyone with towers, start with 7'. If you do the calculations, know the temp you always want to serve at, always like the same volumes of carbonation, always run a fan to keep upper and lower chamber temps equal, can trust the manufacture's claim of per-foot pressure drop, you can arrive at this magic line length that pours perfectly. If you just want to pour some F-ing beer, um..
 
What physics? You're using an empirical formula, not one based in physics. If you were using physics, (really fluid dynamics), you'd need a LOT more information, (wall smoothness, is the line coiled or not, how tight is the coil, where and how many restrictions, turbulence inducing points, etc are there?).

I said this in another post, it seems Todd and I disagree. Some say 5' of line works, some say 10' of line works. All I know is that if 5' of line ISN'T working, you should try 10' of line. There's no "right way" to do this, just figure out how to pour your beer, whatever it takes.

Wait. I know most people use the published formulas and tables all over the place. I have used them too. But you assume that I haven't researched the specifics of the issue. Of course there are a lot more variables at play, but for the sake of serving beer, many of them can be ignored or estimated. And yes, I've looked at more specifics such as friction coefficient of the vinyl hose (which actually varies from brand to brand), coils, tees, elbows, etc, fluid density (we assume 1 which is imprecise) and viscosity, and so on. I don't think anyone is trying to start an argument, but what's wrong with a little edumacation on the subject. Someone might actually learn something. Oh drat!
 
I noticed the last comment about companies using longer lines. 10' of beer line is much more than is needed in the vast majority of sytems. As the owner of a draft beer company I believe it is important to determine the correct restriction length and then use that length on a system. For a standard, typical direct draw system 5' of beer line is more that you need. Putting 10' on will slow down the pour and offers no advantage unless you are serving an extremely highly carbonated beer. If you are getting foam at 12PSI with beer carbonated to serve between 10 and 14PSI your issue is with something other than hose length. It is due to temperature or the beer was carbonated to a rate higher than 12PSI equivalent (due to mistake) If you are serving your beer at 18PSI, you would need longer hose, but it would still not be 10', it would be 6' or 7'. I recently had a customer email me after reading suggestions on Homebrew talk saying his beer line should be 10' long asking why were were being "Cheap" and not installing longer beer lines. My first reaction was to start using longer beer lines, but I know that 10' is way to long and 95% of our customers have great results using 5' beer lines. I think changing the length would have negative results for many customers, including longer pour time, too much beer line to deal with in small spaces and increased cost for something that will give no benefit. We are always happy to put on whatever beer length you desire. Just call us and we will make the change for you. I just don't believe "more is better" is the correct philosophy. I believe it is better to get the correct length and use that.

No offense, but I HAVE one of your systems; 5 feet is TOO short, even at 11 PSI at 42-44 degrees. Now I don't have a tower, and the tap is only slightly higher than the top of the keg, and I am at higher altitude. I ran two different spreadsheets and all said about 3.5-4 feet was the correct length. Not true! 5 feet is too short. More resistance is needed.

I had not believed all those that say that starting with 10 feet and then going down in size is the way to go. I was smug, being an engineer, and didn't order extra line. Well, I was wrong. I do know enough that the formulas work, so one or more of the assumptions are wrong. The line undoubtedly has lower resistance than the formulas, the regulators are probably not all that accurate, and who knows if my temperature regulation is that good. Doesn't matter, really. ALOT of people here are having problems with too short of line. They get by by adding restrictors or longer line.

Nothing at all wrong with doing what works.
 
So what is my problem then. I am running an upright keezer at about 38-40f. I am at about 9-10' of line and am using about 10psi. I dropped it from 12 because I was getting so much foam. I don't know if my beer is carbonated perfectly to style but it is carbonated to my tastes. I still am getting 1/2 to 3/4 pint of foam. If I poor a couple like that then I am good for the next few.

Very frustrating that is for sure.
 
So what is my problem then. I am running an upright keezer at about 38-40f. I am at about 9-10' of line and am using about 10psi. I dropped it from 12 because I was getting so much foam. I don't know if my beer is carbonated perfectly to style but it is carbonated to my tastes. I still am getting 1/2 to 3/4 pint of foam. If I poor a couple like that then I am good for the next few.

Very frustrating that is for sure.

I had similar frustrations when I started kegging. I used 6' lines first, then upped to 7' and finally said screw it and put 10' lines on. No problems now.

My advice is to just go longer lines... just go 12' of 3/16 and see what happens. I currently have 10' of 3/16 lines on 39 degree kegs at 13 PSI and the only time I get any appreciable foam is with a first pour (I don't cool my lines). Even then I can mitigate it by doing a quick blast from the faucet, let it sit a few seconds, then resume pouring.

Longer lines = less frustration. I coil the lines and twist-tie them together in a couple of spots and set them on top of the kegs. It's tidy.
 
So what is my problem then. I am running an upright keezer at about 38-40f. I am at about 9-10' of line and am using about 10psi. I dropped it from 12 because I was getting so much foam. I don't know if my beer is carbonated perfectly to style but it is carbonated to my tastes. I still am getting 1/2 to 3/4 pint of foam. If I poor a couple like that then I am good for the next few.

Very frustrating that is for sure.

How do you carb your beer? Do you have a tower or through wall taps or picnic taps? Does your second beer pour as foamy as the first? (if you pour one after the other?)
 
So what is my problem then. I am running an upright keezer at about 38-40f. I am at about 9-10' of line and am using about 10psi. I dropped it from 12 because I was getting so much foam. I don't know if my beer is carbonated perfectly to style but it is carbonated to my tastes. I still am getting 1/2 to 3/4 pint of foam. If I poor a couple like that then I am good for the next few.

Very frustrating that is for sure.

There is a secondary effect going on besides the line length. IF you are getting good pours after the first or second pour (in succession), this is an indicator that your line and/or faucet is not as cold as the keg. Once you pour 1 or two, it's then cold and pours good. Let it sit, and it's no longer cold, pouring foam the first pour.

Lot's of people put in fans or glycol coolers on the line and/or the faucet to ensure it's cold.
 
There is a secondary effect going on besides the line length. IF you are getting good pours after the first or second pour (in succession), this is an indicator that your line and/or faucet is not as cold as the keg. Once you pour 1 or two, it's then cold and pours good. Let it sit, and it's no longer cold, pouring foam the first pour.

Lot's of people put in fans or glycol coolers on the line and/or the faucet to ensure it's cold.

That is what baffles me. It is a vertical keezer. Lines and shanks all in the freezer coming out the door. No tower or anything else like that. I know it is holding temp pretty well since the probe is in the center and it is not cycling too often. I just don't see how it could be the temp, but nothing else makes sense to me either.
 
That is what baffles me. It is a vertical keezer. Lines and shanks all in the freezer coming out the door. No tower or anything else like that. I know it is holding temp pretty well since the probe is in the center and it is not cycling too often. I just don't see how it could be the temp, but nothing else makes sense to me either.

Ok then, answer the other questions:
How do you carb your beer? Does your second beer pour as foamy as the first? (if you pour one after the other?)
 
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