Auto Siphon Sizing

[jmhbutler]

I snapped my 3/8 autosiphon while kegging last night and I am considering upgrading it to a 1/2 equivalent because it feels it takes an eternity to transfer anything over.

The guy at my LHBS suggested this may be a bad idea because of potential oxidation issues.

What do you guys use? Those using the 1/2 size, do you have problems with introducing O2? Is there any additional precautionary measures you make to avoid this?

Cheers

 

[Bobby_M]

The 1/2" flows much better. I use 7/16" ID tubing for a nice tight fit. To prevent oxidation, flush the keg with CO2 before filling.

 

[poptarts]

While your at it get silicone tubing, the no memory makes transferring so much easier.

 

[jmhbutler]

I'm not sure if my LHBS has 7/16. Will I still be good with 1/2? What about transferring to secondaries or sanke kegs where I don't have the option to easily flush CO2 without taking apart my gas system?

Overall questions - how does the added efficiency compare to the added oxidization risks?

 

[TallDan]

I snapped my 3/8 autosiphon while kegging last night and I am considering upgrading it to a 1/2 equivalent because it feels it takes an eternity to transfer anything over.

The guy at my LHBS suggested this may be a bad idea because of potential oxidation issues.

What do you guys use? Those using the 1/2 size, do you have problems with introducing O2? Is there any additional precautionary measures you make to avoid this?

Cheers

I broke my 3/8" auto siphon and when i when to my LBHS, he recommended the 1/2". I asked if there was any disadvantage to the larger one and he said there was not, it's just faster. He's certainly right about that, and I would definitely recommend it for that reason.

I'm confused as to how the larger one would have more risk of oxidation. It works exactly the same way just with bigger tubing. Did he tell you why it would have more risk of oxidation?

 

[jmhbutler]

I'm not really sure of his explanation why; he said said if I went to the larger size I might have trouble with oxidization. It made me wary but on second thought this guy has give questionable advice before.

So the consensus it to go with the 1/2? Even if I have to use 1/2 tubing and can't always flush with CO2?

 

[MaxStout]

I'm confused as to how the larger one would have more risk of oxidation. It works exactly the same way just with bigger tubing. Did he tell you why it would have more risk of oxidation?

Maybe the LHBS only sells the 3/8" flavor of autosiphon and they want a sale. Otherwise, I cannot think of a scientific reason why using a 1/2" siphon would result in oxidation.

Edit: I'm very happy I moved up to the 1/2" siphon. Much faster transfer.

 

[TallDan]

Maybe the LHBS only sells the 3/8" flavor of autosiphon and they want a sale. Otherwise, I cannot think of a scientific reason why using a 1/2" siphon would result in oxidation.

Edit: I'm very happy I moved up to the 1/2" siphon. Much faster transfer.

The only thing i can think of is that there is more air in the 1/2" tubing than the 3/8" tubing. So, unless you flush the auto siphon with co2 there is theoretically more air that the beer is exposed to.

In practice, I can't imagine that small amount of difference in air volume would lead to any real difference in oxidation. Having an extra foot of tubing on the 3/8" tube would probably completely offset it.

Let's see:

8' of 3/8" tubing (probably enough to cover the siphon and attached tube) would be 2.5 cups of air, 8' of 1/2" tubing would be 3.3 cups. So, an extra 2.5' of 3/8" tubing would more than make up the difference

 

[MaxStout]

The only thing i can think of is that there is more air in the 1/2" tubing than the 3/8" tubing. So, unless you flush the auto siphon with co2 there is theoretically more air that the beer is exposed to.

In practice, I can't imagine that small amount of difference in air volume would lead to any real difference in oxidation. Having an extra foot of tubing on the 3/8" tube would probably completely offset it.

Let's see:

8' of 3/8" tubing (probably enough to cover the siphon and attached tube) would be 2.5 cups of air, 8' of 1/2" tubing would be 3.3 cups. So, an extra 2.5' of 3/8" tubing would more than make up the difference

Good point. And that would be the worst-case situation ONLY if all that air somehow became entrained in the beer. Otherwise, it's just the difference in the cross-sectional area of the inside diameter, where the air meets the top of the column of liquid. And that air/beer interface only lasts a second or two before the moving column of beer displaces the air, and it's all beer flowing from that point forward.

Splitting hairs here, but I think it's a negligible difference between the two sizes, barring some sort of aeration of all that air inside the tubing.

 

[Shuasha]

I actually came across this as an issue for the first time today. Thicker beers (I was transferring a BCBS clone) have an issue flushing the air out of the larger diameter tubing. Lighter stuff has never been an issue, but if you bring the viscosity up, it can take a while when bottling.

It's not an issue when transferring to a keg. I feel the larger diameter is absolutely worth it.