floating diptube issues: problems, causes, fixes, solutions, etc...

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odie

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Seems there are several here who are running floating dip tubes and having issues...mostly sucking air and not beer. So why not start a thread to specifically to talk about how these things work, and why they occasionally fail and what possible solutions you have tried and such? Post your issues and what you did to fix them. Pictures...we all like pictures...

It seems while they all have the same outlet...there are different types of floats and pickups...so it's obviously not going to be one size fits all on the solutions. But all these floating dip tubes seem to work the same way.
 
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I'm running the ones with the round SS float, about the size of a ping pong ball. Has a short 1" SS pickup tube to attach the tubing, silicone in my case. The pickup is attached the float with a small SS split ring. As you can see in the photo, the pickup tube is about 1-1/2" to 2" below the surface. This "should" be ideal. Not so.
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I opened a couple kegs that suddenly stopped flowing beer. What I found was that the float was on it's "side". Yes it's a round float but there is a horizontal seam that somehow rotated vertical and thus pulled/lifted the pickup to the surface, allowing air into the tubing and floating everything to the surface. Why this happened I'm not sure but I have some theory...

I supposed if you are pouring too much beer too fast, like a growler fill, it's possible the headspace pressure will drop and CO2 break out of the beer and fill that headspace with foam. I guess the beer is flowing out faster than the regulator can replace CO2? The problem seems to occur mostly with Hefes and other higher carbed beers. But it recently happened with a lower carbed English style beer too. I theorize that this foam lifts the float, thus lifting the pickup above the beer and the whole thing sucks air and then the entire tubing floats to the top. You don't realize it's happening until the tap stops flowing beer and all you get is CO2 and some foam coming out. By this time the entire silicone hose inside the keg has filled with CO2 and is now floating, pushing the pickup even higher. As you can see in the picture, bubbles easily stick to SS float and pickup tube.

Sometimes I've been able to wait it out and I guess the foam dissipates and the pickup/tubing drop below the surface and fill with beer again. Sometimes I've had to pull the keg, flip it upside down so the float can "rise to the bottom" so to speak, extending the silicone tubing and expel the CO2 and fill with beer again. Sometimes nothing, not filling the keg, not laying it on it's side, rocking it, rolling it, not shaking the keg, nothing will get the tubing and pickup to drop below the surface to expel the gas and let beer back in.
 
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What I'm trying, like others, at the moment is to add some weight to help coax the pickup to stay vertical and down below the surface. I found a 3/8" SS nut slips right over my pickup tube but not over the silicone hose so it will stay in place and keep the nut/weight on the pickup, hopefully forcing the float to go back vertical or stay vertical and allow the pickup to drop/remain below the beer and refill/stay filled with beer and not CO2. I also found that a 1/2" SS nut will slip over the silicone tubing. I hope that this will freely slide down the silicone tubing to the bottom of the "dip" or the halfway point to help keep the tubing fully submerged, so that even if the keg foams and CO2 gets in the line, it will stay down and once everything settles down, beer will flow back into the tubing as the CO2 bleeds back out.
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7/16? It looks like you are running the same floats as me...3/8 is what fit mine, although with no gap ( I wanted to be sure it would not slip down the hose). 7/16 is actually a hair bigger (heavier) and would still not slip down the hose...

I would say 7/16 is probably a better choice than my 3/8. I'll use 7/16 on my other kegs if this works out.
 
7/16? It looks like you are running the same floats as me...3/8 is what fit mine, although with no gap ( I wanted to be sure it would not slip down the hose). 7/16 is actually a hair bigger (heavier) and would still not slip down the hose...

I would say 7/16 is probably a better choice than my 3/8. I'll use 7/16 on my other kegs if this works out.

When my silicone hose is slipped over the pickup tube the nut won't fit over the tubing. While it looks like not much of the tubing is slipped over the pickup, I've never had an issue with it slipping off. Only weakpoint I've had issues with is the ring on the float.
 
I had a similar problem, adding the nut as a weight did the trick for me. Since then I've switched to the plastic filter ends, and haven't needed a weight. I can't remember where I got them, but this is what I'm talking about - Floating Dip Tube Filter
 
Another problem I've had, I was getting some cloudy pours for the last 3 or 4 pints before the keg emptied. I think it was from having too long of a hose and part of it was brushing the bottom of the keg when the volume got low enough. I cut the hose so that the end would hang just above the bottom of the keg and it helped. At the time I was using pinlock kegs, so the hose length was way too long.
 
I don't think that all of the problems are due to the float, as your pictures perfectly demonstrate the intake ( little metal collar) hangs nicely below the surface and would do in all liquids except mercury!
The confounder in fact is the tube, a full keg which is quite narrow such as a corny or a sankey 20 litre will have quite an acute or tight bend on the tube and it is this lack of tube compliance that pushes the collar up in certain situations. I observed this with the fermentasaurus which is clear with a floating dip tube. These are quite wide at the top but as they are a conical narrow towards the bottom, the float always goes to the side of the vessel where it can drag a little and so as it narrows the tube curve becomes tighter and collar rising can occur. This problem is easily noted as it's usually during a transfer so I just bang the side of the fermenter and all is well.
The problem is worse with the gen 3 fermentasaurus as the float is meant to slide up and down the central pole, the aim being to stop yeast pickup during transfer from the vessel side. This yeast pickup can be mitigated by making sure it's not there in the first place.
The central column effectively halves the fermenter diameter and so increases the curve of the tube.
What to do, have a compliant tube ( soft and very flexible), make sure the tube is not longer than the bottom depth of the keg you want to extract from.
Redesign the collar so that it is U shaped one end is in the silicone tube the other end points down to pick up below the surface. This will be heavier than the straight collar and should have the ring on the top the U.
 
Another problem I've had, I was getting some cloudy pours for the last 3 or 4 pints before the keg emptied. I think it was from having too long of a hose and part of it was brushing the bottom of the keg when the volume got low enough. I cut the hose so that the end would hang just above the bottom of the keg and it helped. At the time I was using pinlock kegs, so the hose length was way too long.
All the floating tube kits I've gotten have a longer silicone tube than is needed. Or so I assume. I cut the hose so that the pickup is just touching the bottom when everything is fully extended. There is no extra tubing to coil up inside the keg
 
Remember to test your weighted tube beforehand. I discovered while sanitizing (and a few minutes before go time) that my planned weight was actually enough to sink the floating ball.

In my experience, weight is only part of the problem. The other problem areas are the links between the ball and tube get kinked, sticking the tube up & to the side. The other problem is the tube length itself sticking up against the wall, suspending the tube upward, almost regardless of weight. -The only solutions I've found for these later problems is to just be very careful in the initial placement, being mindful of the tube position & links.
 
The confounder in fact is the tube, a full keg which is quite narrow such as a corny or a sankey 20 litre will have quite an acute or tight bend on the tube and it is this lack of tube compliance that pushes the collar up in certain situations.
I get it, the hose hangs down half way and then bends back up...Silicone always wants to unbend and go straight. So the float is always being slightly pushed against the keg wall. And the silicone tubing is also being pressed against the keg wall. Silicone is "sticky/grabby" so it's got some friction holding it in place, thus resisting gravity as the beer level drops...if it hangs up, the tubing takes in gas and then is even more buoyant and compounds the problem.

This is where a larger nut or SS washer in the middle of the tubing might help greatly, to keep pulling the hose down into the beer.
 
Also, stainless spherical/round weights like fishing weights would be great, if possible, so could attach at various locations along the tube & to prevent scratching that these stainless nuts & washers can cause.

I haven't actually done it yet, but I've considered fitting tube-sized SS washers at 3-4 spots along the tube to create buffer keeping the tube from pressing too much against the sides
 
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I get it, the hose hangs down half way and then bends back up...Silicone always wants to unbend and go straight. So the float is always being slightly pushed against the keg wall. And the silicone tubing is also being pressed against the keg wall. Silicone is "sticky/grabby" so it's got some friction holding it in place, thus resisting gravity as the beer level drops...if it hangs up, the tubing takes in gas and then is even more buoyant and compounds the problem.

This is where a larger nut or SS washer in the middle of the tubing might help greatly, to keep pulling the hose down into the beer.
Or the U shaped modification I mention, could bend a bit of fine copper pipe I suppose and wire that on easily. Not sure if copper in ferment is good, SS is tough to bend though.
The ball actually grabs as well, it's friction. You want the weight fixed at the end not sliding up and down the pipe as it could get hung up.
 
I have two kegs using exclusively floating dip tubes, and I've never had an issue with mine. Just a single 3/8" hex nut, fit snug over the silicone tubing, and it sits low enough to dispense perfectly. Pours great until the keg runs empty.

One thing to pay attention to is the orientation of the tubing as you insert it into the keg. Make sure it loops gently, no sharp twists or bends.
 
Or the U shaped modification I mention, could bend a bit of fine copper pipe I suppose and wire that on easily. Not sure if copper in ferment is good, SS is tough to bend though.
The ball actually grabs as well, it's friction. You want the weight fixed at the end not sliding up and down the pipe as it could get hung up.

Not to be "that guy", but I would not use copper in a fermented beverage. It's a bigger concern for more acidic drinks, but beer has a low enough pH to potentially cause copper poisoning. Your Cocktail Mug Might Be Poisoning You
 
One thing to pay attention to is the orientation of the tubing as you insert it into the keg. Make sure it loops gently, no sharp twists or bends.
well with the silicone tubing that most of these kits come with, The silicone has no "memory" and is very "rubbery". Once unpackaged it will straighten back out and naturally seek a very smooth lay...silicone does not like to be twisted and bent and will always try to flex back to a straight and smooth path.

I think the key here is how much weight and where that weight is placed. I updated some of the pics up top at the beginning...

I note that a 3/8 and 1/2 nut together is enough weight to sink the float. It's not a HARD sink but just barely negative from neutral buoyancy in water. In denser beer it's likely neutral. Some guys are using a 1/2 SS washer which is lighter than the 1/2 SS nut. I passed on the washer initially since at the hardware store, I didn't think it was heavy enough. But I'll grab a washer and try it for a comparison photo.
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But it's likely that the best option is either a single nut at the pick up tube (3/8 or 7/16) is sufficient...OR a 1/2 nut sliding freely on the tubing....but NOT BOTH.... OR even using the lighter nut (3/8) on the pick up and the lighter 1/2 washer on the tubing?
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I have one of the Torpedo Keg units like these and I added a stainless nut as in the picture. I bought Ballandkeg units for the rest of my kegs as they have a weighted tip included. The stainless tubing in the end is heavy enough to keep them submerged. You do have to trim them off to hang just short of the bottom of the keg as is the case with all the units.
 
I have them in (2) 3 gallon kegs and (2) 5 gallon kegs, silver colored float ball like pictured here. No modifications of any kind. I’ve had zero issues since installing them. No problems whatsoever. I really like them.
 
I use a 7/16 nut on my dip tubes. Haven't had an issue since I've started weighting my dip tubes. I use them in my fermenters and kegs.

I've been wanting to use a floating dip tube on my conicals to get clean transfers into a serving keg after cold crashing. The problem is getting the tubing over the uptake end of the ½" O.D. racking arm. How'd you do it?
 
Still trying to figure that one out. Only thing I can think of is JB weld but not sure how food safe that would be...
I was thinking about silver soldering to avoid lead contaminants. Fortunately Williams Brewing replaced the one that broke on me for free, but I've been wondering if there's a safe way to repair the broken one to experiment with in the conical. Even if it detaches inside, I'll at least be drawing from bottom. I might have to dump some good beer at the bottom of the fermenter so that there's nothing but clear beer left to transfer out with no trub, spent hops or yeast.
 
I was thinking about silver soldering to avoid lead contaminants. Fortunately Williams Brewing replaced the one that broke on me for free, but I've been wondering if there's a safe way to repair the broken one to experiment with in the conical. Even if it detaches inside, I'll at least be drawing from bottom. I might have to dump some good beer at the bottom of the fermenter so that there's nothing but clear beer left to transfer out with no trub, spent hops or yeast.
Perhaps I will try that as well. I'll post the results if I do.
 
well with the silicone tubing that most of these kits come with, The silicone has no "memory" and is very "rubbery". Once unpackaged it will straighten back out and naturally seek a very smooth lay...silicone does not like to be twisted and bent and will always try to flex back to a straight and smooth path.
The lack of compliance in the silicone tube is actually memory, if it had no " memory "it would stay in any position that you put it in. The fact it wants to go straight is " memory " and why the float gets pushed to the side of the keg. Also if it didn't have " memory " the tube would collapse as it couldn't " remember" and would always kink closed as soon as it bent.

@EDF713 Thanks for confirming not good / safe for copper in fermenter, need to find a bit of bent stainless or maybe some lab glass, which would be easy to bend and also put a little loop for the ring on it. I'll see if I can get a bit.
Short but thick glass would be pretty strong so unlikely to be broken in a keg.
 
I'm running the ones with the round SS float, about the size of a ping pong ball. Has a short 1" SS pickup tube to attach the tubing, silicone in my case. The pickup is attached the float with a small SS split ring. As you can see in the photo, the pickup tube is about 1-1/2" to 2" below the surface. This "should" be ideal. Not so.
View attachment 757223
I opened a couple kegs that suddenly stopped flowing beer. What I found was that the float was on it's "side". Yes it's a round float but there is a horizontal seam that somehow rotated vertical and thus pulled/lifted the pickup to the surface, allowing air into the tubing and floating everything to the surface. Why this happened I'm not sure but I have some theory...

I supposed if you are pouring too much beer too fast, like a growler fill, it's possible the headspace pressure will drop and CO2 break out of the beer and fill that headspace with foam. I guess the beer is flowing out faster than the regulator can replace CO2? The problem seems to occur mostly with Hefes and other higher carbed beers. But it recently happened with a lower carbed English style beer too. I theorize that this foam lifts the float, thus lifting the pickup above the beer and the whole thing sucks air and then the entire tubing floats to the top. You don't realize it's happening until the tap stops flowing beer and all you get is CO2 and some foam coming out. By this time the entire silicone hose inside the keg has filled with CO2 and is now floating, pushing the pickup even higher. As you can see in the picture, bubbles easily stick to SS float and pickup tube.

Sometimes I've been able to wait it out and I guess the foam dissipates and the pickup/tubing drop below the surface and fill with beer again. Sometimes I've had to pull the keg, flip it upside down so the float can "rise to the bottom" so to speak, extending the silicone tubing and expel the CO2 and fill with beer again. Sometimes nothing, not filling the keg, not laying it on it's side, rocking it, rolling it, not shaking the keg, nothing will get the tubing and pickup to drop below the surface to expel the gas and let beer back in.

I haven't read the rest of the thread yet, but ditto. Glad it's not just me. Now to go back to the top and learn something.

EDIT: OK, I use several of these, and I have used the plastic wine filters mentioned above by @EDF713 also (not always successfully). When it comes to pouring a pint or two, no mods, I usually get good pours. If I am filling a growler for a friend/neighbor, then I have to shake the keg to avoid a nothing-but-foam experience. I am going to dig through my parts drawer and find some SS nuts as recommended by the OP in order to try to solve this issue for the kegs that have them. Thank you all for contributing to our collective knowledge!
 
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I have a couple of the (stock) floating dip tubes from Moorbeer that I use in smaller, 2.5 gallon kegs. The only time I had an issue was when I attached the tubing in such a way where the natural bend of the silicone did not curve towards the kegs center. Now I always make sure the float ball sits naturally in the kegs center dimple before racking. Problem solved.
 
Well, after some more testing with assorted weights and tubing...some surprises...the fender washer is heavier than the nut. I did not grab a regular washer to try yet. I placed some dip tubes in a bucket of water to observe how they hang...for the most part in the test pictures above, using a weight on both the float end and another weight sliding up/down the tubing is too much weight total.

In this picture you see 3 dip tubes. 3/8 nut on the float end, 1/2 nut sliding on the tubing/hose, 1/2 fender washer sliding on the tubing.

The 3/8 nut does keep the float up-right and keeps the pickup below the surface. However, note the tubing...it's not weighted and just kinda does it's thing as it's neutrally buoyant I can see the possibility of it "clinging" to the sides of the keg and possibly causing the pickup to get pushed above the surface.

The 1/2 nut freely sliding on the tubing keeps the tubing down in the proper dip/bend/loop. Blowing air into the tubing and the tubing still stays down low like it's supposed to.

The 1/2 fender washer performed the same as the 1/2 nut. However, the 1/2 fender washer heavier and was able to sink some of my SS floats.

Using a single weight, the 1/2 SS nut sliding freely performed best IMO.

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Tubing....I bought floating dip tubes from 2 different sellers. Although practically identical...the floats are slightly different, one being a tad bit more bouyant.

A bigger difference I think is the silicone tubing...One is notably thicker and more stiffer. See the pictures...obviously the thinner/lighter tubing is preferred IMO.

I think the issue here is going to be others noted above, that the thicker silicone hose will always want to straighten out. Since it's inside a narrow keg and is bent 180', it's going to want to force itself up against the side of the keg. There will be friction resisting the float and tubing dropping down as the keg level drops...Thus the importance of an extra weight on the hose, especially with the thicker hose that some vendor/seller provide.
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As you can see in this picture...there are some variations of floats offered...these look the same but I note that the one without the "side ridge" is slightly less buoyant. It will sink with a 1/2 fender washer but the "side ridge" float will barely break the surface.
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