What is the Proper Tubing Size?

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DrDance

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Hello all, hope this finds everyone enjoying a frosty pint.

I'm making the change to kegging and the one thing that has me totally confused is all the different hose/tubing sizes. I've read numerous posts about what sizes should be used for serving and even gone on to the kegerators.com calculator but it seems everywhere I look there's a different answer.

What size ball locks do I get?(with what size barb?) 1/4", 3/16", 5/16"? And is that ID or OD? Do my lines need to be the same size? (gas & liquid) Or does that matter? I've seen many posts that suggest 5/16" for serving lines but when I put that into the kegerators.com calc it says I need around 116 ft. of line. I assume that's incorrect for a keezer. Even to look up and find 5/16' tubing (like on the kegland site) it comes in various ID.

If anyone has any input that could make this setup a bit easier to understand, that would be wonderful.
 
Good for you for using Mike's beer line calculator. You're already way ahead of the average home brewer :)

Classically, 3/16" inside diameter PVC tubing has been used for beer lines, at roughly 1 foot per psi of CO2 used to maintain the carbonation level of most ales. You can compare that with Mike's calculator which is a bit more aggressive. That line length metric will "tame" the beer flow so you don't slam beer into your glass and cause a foam riot.

That said, with the advent of advanced oxygen barrier tubing ala EVABarrier, if you can get by with just 5 to 6 feet of beer line to your faucets (not always possible) their 4mm ID beer line is superior to anything else on the market. If you need longer lines they also have a 5mm ID version which approaches 3/16" so should allow 10-11 foot runs.

These EVABarrier lines pretty much require using Push-to-Connect fittings with threads that connect to ball lock QDs with 1/4" MFL threads (ie: NOT barbs) at one end, and standard beer shanks with 7/8"-14 (5/8" BSP) threads at the other. You can get the tubing over barbs but it's sub-optimal and can be a pita. Also, many of us running EVABarrier recommend using the same tubing for gas lines to minimize O2 ingress...

Cheers!
 
First, I highly recommend using ball lock QDs that have male flare MFL hose connections so that you can have future flexibility. I have never, and will never, sell molded barb versions of the same. It's a dead end.

EVA barrier tubing is the current hot stuff for liquid lines. You can use the 4mm ID x 8mm OD stuff with either Duotight fittings or you can stretch it over 1/4" barbs by warming the ends of the tubing and flaring the opening a bit with a tapered pointy tool thing.. Over a barb, you'll want an oetiker style hose clamp crimped on. Typical beer pressures will make due with 5-6ft of the EVA tubing for a nice pour.

For the most part, the industry has been out of its ever loving mind with the size of gas tubing that has proliferated. Everyone is selling 5/16" ID thickwall PVC for this. Don't get me started on the rainbow colors where you wouldn't be able to see that you've had beer back up into it, therefore festering sight unseen.
Often the gas tubing size selection is dictated by whatever barb you're forced to deal with. For instance, you might find that the one CO2 regulator you really wanted to buy has a 5/16" barb on the output. In that case, about the smallest tubing ID you can use is 1/4" as it will easily stretch over. If you happen to be able to get all gas equipment with 1/4" MFL flare ports, you're back to able to use EVA, same 4mm ID stuff with the appropriate Duotight fittings or that 1/4" barb we talked about.
 
Additionally there is a 3mm internal evabarrier line. This is very handy for higher carbonation beers such as saisons, witbier etc. Also very useful for picnic taps and mini kegs. But only needed on liquid line in these cases.
The 3mm internal is 6mm external or 1/4 inch compatible.
 
Additionally there is a 3mm internal evabarrier line. This is very handy for higher carbonation beers such as saisons, witbier etc. Also very useful for picnic taps and mini kegs. But only needed on liquid line in these cases.
The 3mm internal is 6mm external or 1/4 inch compatible.
It's very cool but if you want to switch to shanks and faucets, there currently is no Duotight to go from shank to 3mm EVA
 
I would say that the EVA Barrier tubing is more important for the gas lines from an oxygen point of view. Why? The gas line brings stuff in to your beer and those lines just sit there exposed day and night. If they are O2 permeable they are just oxygen conveyor belts right into your keg.

Fortunately EVA Barrier tubing is relatively inexpensive, so use it on both gas and liquid lines if possible.
 
I would say that the EVA Barrier tubing is more important for the gas lines from an oxygen point of view. Why? The gas line brings stuff in to your beer and those lines just sit there exposed day and night. If they are O2 permeable they are just oxygen conveyor belts right into your keg.
OK, but beer in the liquid line is getting oxidized directly between pours. Isn't that a bigger issue? There's like 3 or 4 ounces of beer in a 10 foot line, right?
 
Yes. It is probably 6 & 1/2 dozen of the other as the O2 can creep down into the beer via the liquid line. But at least you can shoot the beer out where the gas always goes in. Both are important. I went with the 8mm for serving and 9.5mm for the gas lines. Luckily the barbs on my regulator set up accepted the 9.5mm EVA with some warm water.
 
I just bought some the 3 mm EVA line and have been struggling with this. Which adapters would work? 🤔
Well there's the duotight 6.35 x 8mm adapter but then you'd need a short piece of 4mm ID EVA to jump that to the beer thread x 8mm duo. Not something I'm interested in. I'll convert many of my lines over to complete 3mm ID stuff when kegland makes a beer thread x 6.35 duo.
 
I'm with @Bassman2003 : Go EVABarrier all the way to minimize oxygen ingress.

I also favor barbs over the (very popular) push-to-fit DuoTight widgets. They're plastic, which sometimes breaks, and sideways pressure on the tubing near the fitting can cause leaks. The DuoTights simplify replacing the tubing, but that's not a frequent task.

As @day_tripper says, it's a PITA to soften the EVAbarrier tubing with hot water and stretch it with an awl or something to then push it over barbs, but with a bit of practice it's really not that hard at all.
 
Wrt the 3mm ID EVABarrier tubing, buyer beware: KegLand has almost no fittings in either their DuoTight or their MonoTight product sets to deal with the 6.35mm OD spec. And as far as the rest of the PTC fitting industry is concerned neither JohnGuest nor DMfit seem to think 1/4" OD tubing should connect to anything to do with beer. They don't have anything to get to 1/4" MFL threads (ala QDs) nor to get to 5/8 BSP (or 7/8-14) beer threads for beer shanks or Sanke coupler connections.

I'd give it a miss and stick with the 4mm ID tubing...

Cheers!
 
Well there's the duotight 6.35 x 8mm adapter but then you'd need a short piece of 4mm ID EVA to jump that to the beer thread x 8mm duo. Not something I'm interested in. I'll convert many of my lines over to complete 3mm ID stuff when kegland makes a beer thread x 6.35 duo.
I've been considering the 3mm ID line myself and there is this;
Food Grade Plastic, 1/4 that I could use to connect it to the duotight tower-shank, but I'm at a loss as to what I could put on the disconnect end... Wondering if it's too far a stretch to try and swag it over a 1/4" swivel-nut.
Other 3mm question; How's the pour-rate on that?
I'd really like to reduce the amount of line hanging in the limited headspace of my kegerator.
 
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I've been considering the 3mm ID line myself and there is this;
Food Grade Plastic, 1/4 that I could use to connect it to the duotight tower-shank, but I'm at a loss as to what I could put on the disconnect end... Wondering if it's too far a stretch to try and swag it over a 1/4" swivel-nut.
Other 3mm question; How's the pour-rate on that?
I'd really like to reduce the amount of line hanging in the limited headspace of my kegerator.
The new duotight QDs do come in 6.35 so that's a direct connection. I make picnic tap lines with the 6.35 OD EVA at 3ft long and it pours about the same as a 5.5ft 4mm line.
 
First I've seen of that - it must be well hidden on their site which I've been pawing over for the last 20 minutes.
Do they sell a compatible beer nut, too?

Compared to the 8mm product set the 6.35mm set for beer dispensing is very thin.
They do have a GHT adapter for some inexplicable reason though...

https://www.kegland.com.au/products/duotight-6-35mm-female-x-bspt-female-thread
Cheers!
 
The new duotight QDs do come in 6.35 so that's a direct connection. I make picnic tap lines with the 6.35 OD EVA at 3ft long and it pours about the same as a 5.5ft 4mm line.
Thanks! I didn't know they did 6.35mm diconnects, however: As much as I love Kegland for their reasonably priced and useful products, I have cause to distrust their ball lock disconnects. When I began kegging, I just bought what my LHBS had on the shelves and these included kegland on no-name disconnects. When I gained a bit of experience and had enough items in my shopping list to place an online order for parts, though the CM Beckers cost $1-something more, I ordered them and had an epiphany... I've had failures and difficulty in the fit with the cheapies, but every CM Becker I have works as good as when I bought it, while I've had to throw out almost every non-CM Becker for leaks or great difficulty in installing and removing. I simple don't trust them to maintain a tight enough spec on disconnects. This thread covers some others with the same concerns: Duotight ball disconnects - experiences?
As it is, as much as I love the duotight fittings, I don't like them where they have to move around... I'm fine connecting my tower-shank with them, but if I push on one of the lines in my kegerator, even with the retaining clips, they can leak and I'd rather keep the flare-fitting end on swivel-nuts.
Is a 3mm ID too much to swag over a 1/4" swivel-nut?
 
Well there's the duotight 6.35 x 8mm adapter but then you'd need a short piece of 4mm ID EVA to jump that to the beer thread x 8mm duo. Not something I'm interested in. I'll convert many of my lines over to complete 3mm ID stuff when kegland makes a beer thread x 6.35 duo.
They are making the ball lock connectors for 6.35 but you do need to step up with a short pipe and adapter to the beer shank.
I've been considering the 3mm ID line myself and there is this;
Food Grade Plastic, 1/4 that I could use to connect it to the duotight tower-shank, but I'm at a loss as to what I could put on the disconnect end... Wondering if it's too far a stretch to try and swag it over a 1/4" swivel-nut.
Other 3mm question; How's the pour-rate on that?
I'd really like to reduce the amount of line hanging in the limited headspace of my kegerator.
There are adapters from john guest that are for 1/4 inch to 8mm ( 5 / 16 I think) that you would need to use to connect into the standard ball lock and to the tap shank.

It's a useful diameter line for cutting down beer line length especially for high carbonation beers.
I'm actually using a 2mm internal line for one saison stepped up to connect with EVA barrier at each end, but I'll be changing to the 3mm EVA internal as the 2mm line isn't EVA barrier.
There's so little line length with it and volume that perhaps I'm being paranoid.
 
Not a major dollar investment to find out, though.
Actually, in my case it kinda is.. My LHBS doesn't have it in stock and it'll be a while before I place an online order as I only do that when I have enough items to reach the free shipping on > $150. I was hoping that maybe someone else on here had swaged a 3mm line over a 1/4" and could say as much...These days, my primary learning comes from the experiences of others :p If I knew for fact it was doable and sustainable, I'd simply order a whole roll (at whole roll discount) so that I could change over all my beer lines at once.
 
Hello all, hope this finds everyone enjoying a frosty pint.

I'm making the change to kegging and the one thing that has me totally confused is all the different hose/tubing sizes. I've read numerous posts about what sizes should be used for serving and even gone on to the kegerators.com calculator but it seems everywhere I look there's a different answer.

What size ball locks do I get?(with what size barb?) 1/4", 3/16", 5/16"? And is that ID or OD? Do my lines need to be the same size? (gas & liquid) Or does that matter? I've seen many posts that suggest 5/16" for serving lines but when I put that into the kegerators.com calc it says I need around 116 ft. of line. I assume that's incorrect for a keezer. Even to look up and find 5/16' tubing (like on the kegland site) it comes in various ID.

If anyone has any input that could make this setup a bit easier to understand, that would be wonderful.
I've always understood it as you choose the size of tubing to minimize the amount of excess tubing you need vs how far you have to run the lines.

Distance you need to run line : Size to choose
0- 10 ft : 3/16 ID
10- 40 ft : 1/4 ID
40-115 ft : 5/16 ID

Home build keezer: you only need maybe 1-2 ft of tubing to reach the shank from the top of the keg so you'll want the smallest diameter tubing to minimize your needed length. (12psi on a 3/16 ID line is 10.1ft of tubing.)

Basement brewery w tap running to upstairs kitchen: Floor to ceiling is 8-10ft plus running over to correct spot say you'll need 20 ft of tubing. Clearly 10ft of 3/16 ID tubing would be too short so up jump up to 1/4 ID. Now you will NEED 39.9 ft of tubing to reduce flow enough by time the beer gets to the tap.

Garage brewery running line underground to house for wet bar in den: say you need about 75 ft of tubing total so now you jump up to 5/16 Id tubing which would NEED 115ft to reduce the flow enough for a perfect pour.
 
True. One also has to factor in the carbonation levels of your beers. I will always have a hefeweizen or Belgian beer in tap which I serve at 18-22PSI right next to maybe an English ale at 13 PSI. Kegs setups are tricky. Some kind of flow restriction (in the disconnect or on the tap) along with 4mm lines of at least 6-7' or longer has been the best approach for me.
 
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Home build keezer: you only need maybe 1-2 ft of tubing to reach the shank from the top of the keg
Maybe for a 2 keg keezer with collar mounted faucets. Otoh, my 14 cf keezer needed 5.5 foot runs for the furthest kegs to reach their shanks up inside the t tower. The 4mm ID EVABarrier worked well for my configuration...

Cheers!
 
I've always understood it as you choose the size of tubing to minimize the amount of excess tubing you need vs how far you have to run the lines.

Distance you need to run line : Size to choose
0- 10 ft : 3/16 ID
10- 40 ft : 1/4 ID
40-115 ft : 5/16 ID

Home build keezer: you only need maybe 1-2 ft of tubing to reach the shank from the top of the keg so you'll want the smallest diameter tubing to minimize your needed length. (12psi on a 3/16 ID line is 10.1ft of tubing.)

Basement brewery w tap running to upstairs kitchen: Floor to ceiling is 8-10ft plus running over to correct spot say you'll need 20 ft of tubing. Clearly 10ft of 3/16 ID tubing would be too short so up jump up to 1/4 ID. Now you will NEED 39.9 ft of tubing to reduce flow enough by time the beer gets to the tap.

Garage brewery running line underground to house for wet bar in den: say you need about 75 ft of tubing total so now you jump up to 5/16 Id tubing which would NEED 115ft to reduce the flow enough for a perfect pour.
Yes, but we're talking about EVA barrier tubing which is also available in 4mm and 3mm ID. I run 5.5 feet of 4mm and it's about the same as 3/16" ID at 12ft. The 3mm would only need about 2-3ft.
 
Yes, but we're talking about EVA barrier tubing which is also available in 4mm and 3mm ID. I run 5.5 feet of 4mm and it's about the same as 3/16" ID at 12ft. The 3mm would only need about 2-3ft.
Figured the concept as a whole still applies. figure out the min length you need and start with the smallest diameter and work your way up till you're within the range of the required length for the proper flow rate.
 
Thread is getting old, but owing to disability it takes me a long time to do anything..
I'm finally trying to give the 3mm EVABarrier, swaged over a 1/4" swivel-nut a try. I didn't bother with hot water, I just got aggressive with the heat-gun. ...in the pics is as far as I was able to get the line over it and I may have used a bit too much heat.
Please; Let you the jury weigh in:
IMG_1525.jpg

IMG_1524.jpg

IMG_1526.jpg
 
Those connections look fine, @Broken Crow . Only very minor deforming of the tubing ends. I see no problems in these super-clear close-up photos.

I have no heat gun so must rely on hot water and an awl when I do this. I'm wondering (not to hijack -- OK, a bit of a hijack): how many gallons of beer before replacing EVAbarrier. Mine's about 3 years old, so about a dozen batches in each of four beer lines.
 
Those connections look fine, @Broken Crow . Only very minor deforming of the tubing ends. I see no problems in these super-clear close-up photos.

I have no heat gun so must rely on hot water and an awl when I do this. I'm wondering (not to hijack -- OK, a bit of a hijack): how many gallons of beer before replacing EVAbarrier. Mine's about 3 years old, so about a dozen batches in each of four beer lines.
I was worried about deformation too, but looking close and wiping it....at the end, it's mostly keg lube... I do worry though, what effect to O2 permeability the heat gun may cause.
I too have wondered how long to wait before replacing lines...I figured I'd do it when the colour tone changes. I keep pictures of them when brand new and look at them with the same lights when the pic was taken, but yeah; Not a highjack, but still the same area this thread's evolved into. I'm curious too, about others criteria for new lines.
:mug:
 
what effect to O2 permeability the heat gun may cause.
I've read that the inner lining can be disarranged by inserting the barb. That doesn't appear to have happened to your connections though it could be hard to tell.

I suppose heat could alter the properties of the plastics somewhat... maybe. But it's brief and probably not that hot, else you'd probably see greater deformation.

Keep in mind that the affected area (which is probably just fine anyway) is tiny, so not gonna be a major source of oxygen intrusion even if imagined to be somewhat more permeable than the virgin tubing.

In other words, though it's guesswork, I think you can relax on this point. 🍺😎
 
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I'd say well done with that connection, it looks good.
Regular caustic and sanitising to control beer stone and bugs is my priority. Not sure I've seen deteriorating performance on my evabarrier at 3 years. Swapping a new piece in for a comparison would be difficult as I'm not blind to the change
 
I'd say well done with that connection, it looks good.
Regular caustic and sanitising to control beer stone and bugs is my priority. Not sure I've seen deteriorating performance on my evabarrier at 3 years. Swapping a new piece in for a comparison would be difficult as I'm not blind to the change
There's a thread on here I can't find, where folks have posted experience and pics of Star San deteriorated Duotight fittings. I have to use a 'monotight' 6.35mm fitting for the Nuka-shank end.... I'll probably just stick with hot PBW followed by a rinse and toss the first cup after cleaning. (...IF it works out!)
 
The thread you are seeking details the issue with starsan. The .problem seems to occur when starsan is sprayed on the duotight or copies and then left to dry. This means higher concentration of acid, new duotight is a different formulation said to be resistant. Internal use is fine as it will be flushed out by water or beer. Certainly warm PBW or caustic line cleaner then water flush and then starsan has not caused beer or connection issues for me.
 

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