Conical fermenter drain question

[DamnRedhead]

Hello,
I'm brewing with a group of people from work, and we have a 10 gallon conical fermenter with a 1/2" threaded drain towards the bottom. They have it going down to a 5/16" hose through a threaded to barbed adapter, and it takes FOREVER to drain.

I was thinking of replacing it with at least a 3/8" or maybe 1/2" tube to drain from. I mentioned this to one guy who's been around for a while and he said they used to have it drain into a 3/4" hose, but because it was so much larger it would make air mix in with the beer, so they went really small.

Wouldn't a 1/2" hose be perfectly fine? I don't want to waste money, time, or look like too much of an idiot.

 

[Johow]

I'm not a pro but I do think you want the hose to be completely full of liquid while racking so as not to aerate the fermented beer.

 

[DamnRedhead]

Yeah definitely Johow... I just want to know the max size tube I can use without aerating it.

 

[Johow]

I don't own a conical but I use 3/8 tubing for racking from my fermenter and it works well and doesn't seem to take too long.

 

[itsme6582]

Can you get your fermenter up a little higher? When you open that bottom port your actually siphoning. You might see enough improvement with what you have if you can just get a bigger height difference.

 

[jddevinn]

Going out of the bottom of a conical is't a siphon.

si·phon
ˈsīfən/Submit
noun
1.a tube used to convey liquid upwards from a reservoir and then down to a lower level of its own accord. Once the liquid has been forced into the tube, typically by suction or immersion, flow continues unaided.

Are you gravity draining or pushing with CO2? Either way if you have a closed connection on the keg the hose can be as big as you want. There is nowhere for air to ingress in and the QDC on the keg should be the flow restrition point.

 

[evilsmurfkiller]

I don't know what their setup is, I pressurize with CO2 and rack to the keg out port with a 1/4" ID line. Takes a while but will not touch any oxygen that way.

 

[itsme6582]

It is a syphon and a bigger height difference will work.

Thats not a good definiton. Flow doesn't continue unaided. Differential pressure pushes it.

With enough tube you can test this. Once it's going, just move the middle of the tube up above the fermenter and the flow will continue. Moving the tube up doesn't make it a syphon but it does demonstrate differential pressure is moving the beer and you have a syphon.

 

[VladOfTrub]

Is the drain in the bottom of a sink called a syphon?

Follow what the brewer said about using CO2.
I use 42 gallon Blichmann conical fermenters and inject CO2 into the blow off attachment to keep air off of the beer when transferring to kegs through 3/8 ID Sillflex tubing. The beer is pushed through the outlet of the keg, filling from the bottom up. The racking port is 1/2" NPT tri-clover fitting. No issues with air bubbles in the transfer line. Kegs fill in no time. I am anal about air in the kegs and lines because the beer that I brew conditions for months due to being naturally carbonated.

 

[itsme6582]

If your plumbing isn't vented correctly your p traps can be siphoned dry and your toilet drains via siphon.

 

[VladOfTrub]

Plumber's mantra: Don't chew fingernails, water runs down hill and payday is on Thursday.

I believe that a conical has a port on top for a bubbler or blow off, I'd call that a vent or no? P-traps dry out, for that reason it is recommended to add water to drains that aren't often used.