# Insanely foamy homebrew from homemade kegerator: Tried almost everything

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#### Prateek Garg

##### Member
Hi, people!
I'm a homebrewer in India. But I've been brewing Kombucha (a fermented tea) instead of beer for now. I retrofitted an old fridge with a beer tap to make a kegerator of sorts.
I brew my Kombucha in glass jars, and then pour it in a used pin lock corny keg I picked up from a store. I then try to force carbonate my Kombucha by adding CO2 from a pressurized CO2 cylinder.
Here is how my system looks like during the dispensing. And there's a head of 90+%; basically only foam seems to come out of my tap and the liquid beneath is super flat after the foam settles.

Apologies for a long, long post ahead but I've mentioned all the troubleshooting I've tried to do by reading this forum and watching youtube and nothing has worked so far:

1. I've tried slow and fast carbonation both (fast = adding about 30psi of pressure and rocking the keg for 5-10 minutes; slow = keeping the keg at 16-18psi for a 10 days). Both of these give the exact same result with the same amount of foam dispensed and flat liquid.

2. I've read almost everything there is about pressure balancing the kegerator. I have mostly used this source: http://www.mikesoltys.com/2012/09/17/determining-proper-hose-length-for-your-kegerator/ (recommended by Draft System Balancing or How To Fix Foamy Beer)
to make all sorts of calculations about my hose length. Tried with different hose inner diameters and dispensing pressures and no matter what, there is **** load of foam from the tap, even when I use like 2 psi dispensing pressure at a 8 feet length of 4mm hose (which, according to the calculations should balance about 14 psi of pressure). As you might see from the pictures, I have two connectors in the middle; that's because my disconnectors are made for the 1/4'' beer lines but 1/4'' lines would need about 35+ feet of hose length for 14 psi (very long even for 10psi). So, I've used 4mm lines (about 0.15'') and 8 feet of those but no positive result whatsoever. At some point I troubleshooted for the multiple connectors in the line, and I used the same single 1/4'' line, 8 feet of it, but a dispensing pressure of 1.5 psi, but still that same **** load of foam with super flat liquid after the foam disappears.

3. When I open my keg after I try and fail at dispensing any decent liquid out and just dip my glass in the keg to get some liquid out, that liquid is super tasty and very well carbonated, but no matter what dispensing pressure or hose length I use I don't get a decent pour out (same too much froth but no carbonation in the liquid)

4. This might be an obvious point but I'll state it anyway. When I only put the Kombucha in the keg and dispense it out, it's just good pure liquid out, but as soon as I carbonate the liquid in the keg, I don't get almost any liquid out.

5. I do manage to get only liquid out in just one way: When I put the dispensing pressure like super, super low like barely just putting enough CO2 in to just get the liquid out. This pressure might be equivalent to maybe 0.1 psi or something; no way of knowing; the least count of my regulator is 1 psi. However, when this way only liquid comes out, the liquid is still flat (no carbonation retained) but when I immediately after open the keg and dip my glass in, the liquid inside is properly carbonated; it's just not retained when it comes out.

6. I've checked the temperature and it's super low; like 4-5 degree celsius (39-42 degree fahrenheit), no issues there I believe.

7. I've also tried doing the same thing with a store bought bottled beer; made it flat by leaving it open for a while, poured it in the keg, carbonated it. Same result. So I don't think it's about Kombucha per se (or its ability or inability to retain carbonation; this is also refuted by the fact that the Kombucha liquid inside in indeed properly carbonated)

8. I've tried with two different kegs. Two different taps. Two different sets of disconnectors. Same result. It's possible that all are bad for some reason. But unlikely, I guess.

Thanks for reading this long article; please let me know what you think might be going wrong.

#### camonick

##### Mediocre brewer... Expert drinker
That in-line connector could be causing problems but I don’t think your lines are nearly long enough. With my experience, I have found you need at least 1 foot per psi using 3/16” ID tubing. If you’re serving at 16-18 psi, 20 feet of tubing would be a good place to start.

OP
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#### Prateek Garg

##### Member
That in-line connector could be causing problems but I don’t think your lines are nearly long enough. With my experience, I have found you need at least 1 foot per psi using 3/16” ID tubing. If you’re serving at 16-18 psi, 20 feet of tubing would be a good place to start.
I see. However, my lines are narrower than 3/16''. They're 0.15'' as against 0.1875'' (3/16''). The calculation says that I should need not more than 7 feet for 14 psi. I have more than that, and I've tried dispensing at lower pressures as well as I've written above. I've also tested the in-line connector thing as mentioned in the point 1 above by using a single tubing of 1/4'' and using 8 feet of it against a 1.5 psi of dispensing pressure but same insane amount of foam.

P.S. Wherever I've used the word 's h i t', it's been changed to 'poopy' But now I can't change it to anything else.

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#### bleme

##### Well-Known Member
Are you opening the tap all the way? If you opened it just a little like you are trying to control the flow, it would do exactly what you are talking about.

Another possible cause would be if you have a bad o-ring on the inside of your out-post. That lets air in the headspace mix with the liquid being dispensed.

7' of 4mm line should work, but I'm not sure what happens when you open it back up to 1/4". I'm guessing that isn't the problem but it's possible...

#### doug293cz

##### BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
Your lines don't look like vinyl beer line. If they are a different material, it may have a lower coefficient of friction, which would require more line than the calculator says you need. Do you know what material you lines are made from?

Also, 4mm ID works out to 0.1575" so I would use that in the calculator, rather than 0.15". That small diameter difference makes a 10% difference in the cross sectional flow area.

Finally, are your lines in the keggerator with the keg, and is your tap mounted in a way that it will be cooled by the keggerator? Warm lines and warm taps can cause CO2 breakout during the pour. A fan in the keggerator can eliminate temp gradients inside that could cause your lines to be too warm.

Brew on

#### bleme

##### Well-Known Member
I also see a picnic tap in your pic. Does that do the same thing?

#### Bubbles2

##### Well-Known Member
How is it that when you "dip" into the keg you have carbonation and then if you disperse from tap there is none after foam settles, it is Flat? There is Zero carb from dispensing but dipping into it there is?

I have read quick disconnects often create foamier pours....Yet that should NOT remove carbonation from your liquid.

You are holding 15 p.s.i at 38ºf for 10 days, this after force carbing at 30 for 24 hours....Correct?

Now if you leave that original 30 in there and only back off your low pressure reg to 15 you still have that 30 in there. Yet it should not be Flat. Foamy Yes, Flat No.

I also only see one side connected.

#### doug293cz

##### BIABer, Beer Math Nerd, ePanel Designer, Pilot
Staff member
Mod
How is it that when you "dip" into the keg you have carbonation and then if you disperse from tap there is none after foam settles, it is Flat? There is Zero carb from dispensing but dipping into it there is?

I have read quick disconnects often create foamier pours....Yet that should NOT remove carbonation from your liquid.

You are holding 15 p.s.i at 38ºf for 10 days, this after force carbing at 30 for 24 hours....Correct?

Now if you leave that original 30 in there and only back off your low pressure reg to 15 you still have that 30 in there. Yet it should not be Flat. Foamy Yes, Flat No.

I also only see one side connected.
Foam is formed when CO2 comes out of the beer. In an excessively foamy pour, most of your carbonation can be lost to the foam. Excessive foam and flat beer in the glass quite often go together.

If you pressurize at 30 psi for a time that is not enough to come to equilibrium with the 30 psi in the headspace, and then turn the pressure down (without venting) the pressure in the headspace will go down as the CO2 is absorbed into the beer. You will not maintain 30 psi in the headspace.

Brew on

#### Bubbles2

##### Well-Known Member
Well then if I was the OP I would remove the quick disconnect, adjust the p.s.i after venting IF force charging, that should iron out the foam and removal of Co2. IF the foam persists then your hose line needs to be of the material the calc calls for to be applicable. To test you could charge, vent and reduce p.s.i to 10 and see how it pours with that QD out of the line.

#### estricklin

##### Supporting Member
HBT Supporter
That in-line connector could be causing problems but I don’t think your lines are nearly long enough. With my experience, I have found you need at least 1 foot per psi using 3/16” ID tubing. If you’re serving at 16-18 psi, 20 feet of tubing would be a good place to start.
This is where I'd bet my money. I understand his lines may be slightly smaller than 3/16, but 20ft of line makes a huge difference. Forget what the calculators say, I've learned this the hard way.

A bad gauge on your regulator could be causing this as well.

Your serving pressure should be so low, that liquid barely flows out, turn it down as low as you can, this will help to make up for the shorter lines you have somewhat.

OP
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#### Prateek Garg

##### Member
Are you opening the tap all the way? If you opened it just a little like you are trying to control the flow, it would do exactly what you are talking about.

Another possible cause would be if you have a bad o-ring on the inside of your out-post. That lets air in the headspace mix with the liquid being dispensed.

7' of 4mm line should work, but I'm not sure what happens when you open it back up to 1/4". I'm guessing that isn't the problem but it's possible...
Well, I've tried opening the tap to its full as well. Same result.

The bad o-ring could be an issue and honestly seems like the most plausible thing at this point of time now that I've tried everything else. However, I have two kegs and they both give the same result.

I don't also know what happens when my 4mm lines open up to 1/4'' but I've no choice. My disconnectors are made for 1/4'' inch and balancing 12-14psi serving pressure with 1/4'' lines require more than 30 feet of tubing. I've tried using a single tube of 1/4'' of 8' and 2 psi serving pressure (which should theoretically be balanced) but it gives the exact same result.

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OP
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#### Prateek Garg

##### Member
Your lines don't look like vinyl beer line. If they are a different material, it may have a lower coefficient of friction, which would require more line than the calculator says you need. Do you know what material you lines are made from?

Also, 4mm ID works out to 0.1575" so I would use that in the calculator, rather than 0.15". That small diameter difference makes a 10% difference in the cross sectional flow area.

Finally, are your lines in the keggerator with the keg, and is your tap mounted in a way that it will be cooled by the keggerator? Warm lines and warm taps can cause CO2 breakout during the pour. A fan in the keggerator can eliminate temp gradients inside that could cause your lines to be too warm.

Brew on
Yeah the vendor said the material is nylon. I'm sure it has a different coefficient of friction than vinyl, but I've messed around with the calculator a lot and found that the coefficient of friction isn't a very important variable. Even a 10x change in that number either way doesn't change the required line length significantly (~10% change in the line length). And, as I've mentioned, my system is very troublesome. Even a 2 psi pressure isn't being balanced by 8 feet of length (too much foam) which makes me thing that the pressure unbalancing isn't really what's primarily happening.

Yes, I did use 0.1575'' but lazily wrote 0.15'' in the post but shouldn't matter for the same reason I've written above.

This outer metal tap isn't really being cooled too much by the fridge because it's outside but the lines are being cooled. They're in all the time. I guess, however, that it's the same thing with all such homemade systems though that the tap is outside and doesn't get cooled so much. But I've troubleshooted for this too earlier by using that other picnic tap put inside the fridge all night and then used to pour the liquid out. Same problem persists.

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OP
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#### Prateek Garg

##### Member
I also see a picnic tap in your pic. Does that do the same thing?
Yup. Exacts same thing.

OP
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#### Prateek Garg

##### Member
How is it that when you "dip" into the keg you have carbonation and then if you disperse from tap there is none after foam settles, it is Flat? There is Zero carb from dispensing but dipping into it there is?

I have read quick disconnects often create foamier pours....Yet that should NOT remove carbonation from your liquid.

You are holding 15 p.s.i at 38ºf for 10 days, this after force carbing at 30 for 24 hours....Correct?

Now if you leave that original 30 in there and only back off your low pressure reg to 15 you still have that 30 in there. Yet it should not be Flat. Foamy Yes, Flat No.

I also only see one side connected.
Yes, that's exactly what's happening. The liquid inside is carbonated (when I dip a glass and get the liquid out) but as soon as I get it out via the system, it's super foamy and flat af.
What is an alternative to using the quick disconnects though? It does seem to me that there's some problem there, but I've two sets of quick disconnects and they're giving exactly the same result.

I tried doing both methods of carbonation separately to see if the carbonation method was the culprit or not. The fast carbonation where I put 30 psi and rocked the keg for a few minutes and settled for 24h, and the other method where I kept it at 18 psi for 10 days following the so-called slow carbonation. Exact same result.

Yes there's just one side connected in the photo, because the pressure was kept at a very very low amount that I can't even see it in my regulator. So, I just flush in a little bit of CO2 and just let the liquid come out. That's like the only way I don't get insane amount of foam. But this is pretty useless because at this level of head pressure, I'm going to lose my carbonation in the liquid. I need to be able to dispense carbonated liquid at 12-14 psi.

OP
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#### Prateek Garg

##### Member
Well then if I was the OP I would remove the quick disconnect, adjust the p.s.i after venting IF force charging, that should iron out the foam and removal of Co2. IF the foam persists then your hose line needs to be of the material the calc calls for to be applicable. To test you could charge, vent and reduce p.s.i to 10 and see how it pours with that QD out of the line.
I'm really sorry but I did not at all understand what you've suggested here except that you've suggested to use the material that the calculator calls for. But I've messed around with the calculator a lot and found that the coefficient of friction isn't a very important variable. Even a 10x change in the coefficient of friction either way doesn't change the required line length significantly (~10% change in the line length). And, as I've mentioned, my system is very, very troublesome. Even a 2 psi dispensing pressure isn't being balanced by 8 feet of length (too much foam) which makes me think that the pressure unbalancing isn't really what's primarily happening.

#### camonick

##### Mediocre brewer... Expert drinker
If multiple kegs are producing the same results, it is either your carbing procedure or your lines. (Possibly a combination of both)

When you reduce your regulator pressure to 2 psi, are you venting your kegs headspace also?
I think it would behoove you to figure out how to eliminate the in-line connector because it’s unnecessary in my opinion. 1/4” barbed fittings and 3/16” tubing is very common... just soak the end in very hot water and slide it onto the barbed fitting while it’s still soft and pliable.
I need to be able to dispense carbonated liquid at 12-14 psi.
Forget what the calculators are saying and if you’re using 4mm or 3/16” lines or whatever, a continuous piece of that tubing that is 15+ feet long will likely solve your problems assuming your kegs headspace and regulator are truly 14 psi. If you find the pour is too slow, you can trim the line a little bit at a time to satisfy your needs.
All of these solutions have been mentioned above by @Bubbles2 , @doug293cz and @estricklin.

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#### camonick

##### Mediocre brewer... Expert drinker
While it takes more time and patience, the set and forget method of carbonating your beer is by far the most reliable and accurate way to do it. Assuming your regulator is accurate it is essentially a fool proof way to achieve your desired carbonation.

#### bleme

##### Well-Known Member
Whether using the metal tap or a picnic tap, it has to be operated always fully on (depressed) or fully off to minimize foam. The only time I open it partly is at the end of a pour if I want more head (for appearance) or if I am wanting to de-carb it for a hydrometer reading.

Also, dropping the pressure in the headspace makes the liquid move slower, but it doesn't change the pressure in the liquid. That is still going to be 18 PSI.

If your glassware isn't completely clean, that can cause foaming also, but not as much as you are describing. https://www.kegworks.com/blog/beer-clean-glass/

If it were me, I'd connect the picnic tap, disconnect the gas, vent the headpressure, set a clean glass on top to chill also, wait 24 hours for it to equalize. Some of the CO2 in the liquid will re-pressurize the headspace, resulting in a less carbonated beverage. Without hooking up the gas, try dispensing with the plunger completely depressed. If it is carbonated enough, turn the pressure on your gas way down and reconnect. Gradually turn it up until you hear air flow and you will know what your new PSI level is.

If it pours better but isn't carbonated enough, you know that you need longer lines.

OP
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#### Prateek Garg

##### Member
If multiple kegs are producing the same results, it is either your carbing procedure or your lines. (Possibly a combination of both)

When you reduce your regulator pressure to 2 psi, are you venting your kegs headspace also?
I think it would behoove you to figure out how to eliminate the in-line connector because it’s unnecessary in my opinion. 1/4” barbed fittings and 3/16” tubing is very common... just soak the end in very hot water and slide it onto the barbed fitting while it’s still soft and pliable.

Forget what the calculators are saying and if you’re using 4mm or 3/16” lines or whatever, a continuous piece of that tubing that is 15+ feet long will likely solve your problems assuming your kegs headspace and regulator are truly 14 psi. If you find the pour is too slow, you can trim the line a little bit at a time to satisfy your needs.
All of these solutions have been mentioned above by @Bubbles2 , @doug293cz and @estricklin.
I kind of gave up for a while. But I'm on it again. Yes, when I say that I reduce the pressure to 1.5 or 2psi, I mean I do it by venting the keg. I stop the gas flow from the cylinder and then vent the head pressure to reduce it to 2 psi, and then I've used 8+ feet of single 1/4'' inch tubing which should theoretically be balanced, right? But I see absolutely no difference in the amount of froth. So, I'm not too keen on investing in a new super long 3/16'' inch tubing and higher head pressure because I don't think it'll work if the earlier didn't.
Also, I don't get what is wrong with my carbing method. I've tried both styles of carbing (slow keep and forget, and fast agitation one). Both carb my liquid well as the liquid is super well carbonated when I open the keg and dip a glass into my keg. But that carbonation isn't retained once I get the liquid out via the hose and the tap.

OP
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#### Prateek Garg

##### Member
I
While it takes more time and patience, the set and forget method of carbonating your beer is by far the most reliable and accurate way to do it. Assuming your regulator is accurate it is essentially a fool proof way to achieve your desired carbonation.
I don't really think my problem is the incorrect amount of carbonation as found out by dipping glass into the keg and drinking that one (It's amazingly well tasting. People go absolutely gaga over it) but the fact that all the carbonation basically just comes out of the liquid in my pouring system and all I get is too much undissolved froth and flat liquid.

OP
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#### Prateek Garg

##### Member
Whether using the metal tap or a picnic tap, it has to be operated always fully on (depressed) or fully off to minimize foam. The only time I open it partly is at the end of a pour if I want more head (for appearance) or if I am wanting to de-carb it for a hydrometer reading.
I do keep it fully on.

Also, dropping the pressure in the headspace makes the liquid move slower, but it doesn't change the pressure in the liquid. That is still going to be 18 PSI.
Yes I know that too. But as you've stated later, it will in a long time lead to less carbonated beverage, as the CO2 in the liquid will balance out of the headspace vapour pressure.

If your glassware isn't completely clean, that can cause foaming also, but not as much as you are describing. https://www.kegworks.com/blog/beer-clean-glass/
They're super clean and super cold. No difference.

If it were me, I'd connect the picnic tap, disconnect the gas, vent the headpressure, set a clean glass on top to chill also, wait 24 hours for it to equalize. Some of the CO2 in the liquid will re-pressurize the headspace, resulting in a less carbonated beverage. Without hooking up the gas, try dispensing with the plunger completely depressed. If it is carbonated enough, turn the pressure on your gas way down and reconnect. Gradually turn it up until you hear air flow and you will know what your new PSI level is.

If it pours better but isn't carbonated enough, you know that you need longer lines.
I've done it. What I get is a super super frothy pour (not even liquid and then the CO2 coming out of it, but just like froth directly from the tap) with a super flat liquid.

#### bleme

##### Well-Known Member
That sure sounds like classic bad o-rings. Air is a lot easier to move than liquid so when you have any breach on the liquid out, air blows through the o-ring and turns the little liquid into foam. If you can get Keg Lube, it really helps that o-ring seat properly. Vasoline will work in a pinch.

I've also heard of pin holes in the stainless dip tube, but that is 1-in-1000.

#### Electricbrew

##### Well-Known Member
I would agree to replace the o rings, they are cheap enough and do dry out over time.

Also, dropping the pressure in the headspace makes the liquid move slower, but it doesn't change the pressure in the liquid. That is still going to be 18 PSI.
I also agree with this, and if you’re dismissing longer lines as the solution by saying you only vented the keg and didn’t degass the liquid then I would say that could still be your problem (not saying it is, just saying the dissolved co2 is what needs to be balanced with your lines not the head pressure). You would have to degass by venting, shake keg, vent, shake keg, vent... and so on until it’s flat then set low pressure and recarb to that low level.

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#### Prateek Garg

##### Member
That sure sounds like classic bad o-rings. Air is a lot easier to move than liquid so when you have any breach on the liquid out, air blows through the o-ring and turns the little liquid into foam. If you can get Keg Lube, it really helps that o-ring seat properly. Vasoline will work in a pinch.

I've also heard of pin holes in the stainless dip tube, but that is 1-in-1000.
View attachment 642015
I'm going to get some o-rings in my adjacent city tomorrow. I couldn't find the internal o-rings here. But does that still makes sense if (as I've explained in the first post) when I put a non-carbonated brew in my keg, at whatever dispensing pressure from 2psi to 20psi, and whatever length of the hose from 1/2 a foot to 30 foot, I don't get any foam whatsoever. So, if the air was being sucked into the system somehow, wouldn't I see it in such cases too. Why does it only happen when I carbonate my brew, slow (set and forget) or fast (agitation for a few minutes)?