Bubbles in Auto-Siphon

[dnelson1025]

Hello,

So I am a new homebrewer and am ready to brew my first batch, so I decided to test out my equipment and make sure I knew how to use everything before I start. When I was testing out the auto-siphon, bubbles started forming a few minutes after siphoning started. I'm just siphoning water from a kettle to a bucket to test it. In the beginning, when the kettle is full, the water flows with no bubbles, but as the kettle loses water, when the water level is about 3 or 4 inches high, bubbles start to enter the auto-siphon from the bottom (at least that's what it looks like) and I can't figure out what the problem is. Does anyone have any insight on this? Thanks a lot.

 

[Suthrncomfrt1884]

It's air getting in through the bottom. Keep it under the liquid level and you'll be fine.

 

[Catt22]

Sometimes they will get an air leak where you have the tubing attached. I push the tubing up onto the hook part as far as I can and if I see any bubbles, I use a nylon wire tie to clamp the tubing more firmly. I think the problem is that the OD of the auto siphon cane part is too close to the exact ID of the 3/8" tubing and sometimes it isn't an air tight fit. It would be better if the tubing were just a tad smaller or the cane part a tad larger. I've also noticed that this can be a problem when using some tubing, but not other tubing. That may have to do with the quality control or manufacturing tolerances for the ID of the different tubing. It can be a PIA, but the nylon wire ties cure it every time, so I deal with it.

If the bubbles are originating down lower, it may be that you do not have the plunger depressed to a point below the liquid level in the kettle and this can cause it to suck air past the plunger in the large tube. Keep the end of the plunger pushed down to the bottom of the big tube to prevent this.

 

[bendavanza]

What Catt22 said. It helps to warm the tubing in hot water so you can get it further onto the racking cane. Word to the wise, auto siphons do not like hot water, they get brittle. Also store the cane outside of the tube to keep the seal in good shape.

 

[dnelson1025]

I have the tubing pushed down pretty far on the cane. It looks like the bubbles are starting on the bottom of the auto-siphon; I can see them travel all the way up the cane, and then down the tubing. The plunger is still well below the water level in the kettle when the bubbles start forming down there. I keep it pushed all the way down as soon as the siphon gets going. Could it just be a bad auto-siphon? The plunger doesn't seem to have an airtight seal with the casing like a syringe would. Could that be the problem?

 

[jldc]

I can't use 1/2" ID tubing with my 1/2" auto-siphon. I have to use 7/16" or something like that. Otherwise bubbles.

L

 

[Beezer94]

I use these snap grip hose and tube clamps:
http://www.usplastic.com/catalog/item.aspx?itemid=23427&catid=858

copy and paste the text of the link since this forum's nonsense url bs isn't working

 

[zymurgy101]

I have the tubing pushed down pretty far on the cane. It looks like the bubbles are starting on the bottom of the auto-siphon; I can see them travel all the way up the cane, and then down the tubing. The plunger is still well below the water level in the kettle when the bubbles start forming down there. I keep it pushed all the way down as soon as the siphon gets going. Could it just be a bad auto-siphon? The plunger doesn't seem to have an airtight seal with the casing like a syringe would. Could that be the problem?

I've experienced the same problem with more than one racking cane. The last one I purchased has been the best. You're right though, the bubbles come from the bottom of the racking cane, not at the junction of the tubing and the racking cane. I decided to remedy the problem...I ordered a 14 gallon MoreBeer conical!

 

[dnelson1025]

OK, thanks for the help. I think I just might try another way to start the siphon. It seems that the auto-siphon is more trouble than it's worth.

 

[bendavanza]

I'd contact the store or manufacturer. I have had 2 auto-siphons with no issues.
I would imagine the seal is compromised or not sealed properly.

 

[pjj2ba]

Your problem is with the seal at the bottom of the "piston". I would recommend storing the siphon as two separate parts to avoid the seal getting set in a compressed state.

Things to do to help deal with a wonky seal while using:

Try a little keg lube on the seal so it seals better

Let the siphon sit in the beer for a minute. Some beer will leak past the seal up into the barrel. This bit of beer above the seal, acts like a second seal.

Finally and maybe most importantly, DON"T SIPHON SO FAST! The greater the height difference the more suction you will develop and are more likely to suck air in. Patience is the key. Don't make the height difference so large. Yes, it will take longer to siphon, but you are much less likely to suck any air in.

 

[dnelson1025]

Thanks for the help. I siphoned slower, and no bubbles!