Air Lock vs. Blow Off Tube

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goswell

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Hi,

I read alot about Airlocks clogging and then pressure building up which can cause a big mess. The solution to a clogged airlock seems to be using a blow off tube.
My question is why use an airlock at all? Why not just use a blowoff tube for primary fermentation?
 
I ferment in the cold range and rarely have a fast eruptive fermentation. I prefer airlocks because you dont have to worry about holding a tube in place. Just add a little star san and stick the airlock in.
Edit: I should also mention I have pets & a 2year old, requiring the tube to be HELD IN PLACE, they dont mess with the airlock.
 
It all depends on your primary fermentation vessel.
If I ferment in a carboy I tend to use a blow off tube.
If I ferment in my Stainless stell conical, I use an airlock
If I ferment in my 17.5 gallon bucket, I don't use either, and go with the open fermentation method.

It really depends on your setup.
 
I usually use a blow off tube to get through primary fermentation then switch to an air lock once things subside. The main reason I switch is convenience. A blow-off tube and bottle or bucket is two more loose items I have to work around in my tight brew closet and if I have to move the fermenter I have to move all three items together. Airlocks are compact and firmly attached to the fermenter so there is less worry.
But other wise there is no real need to use airlocks in replace of blow-off tubes.
Craig
 
I personally like airlocks much better. So much so that I'm going to have to get a "huge" fermenter in order to do wheat beers without a blowoff tube. I just can't manage to keep the blowoff water "clean" long enough. Nasty stuff starts building up overnight and swapping that out every other night is no fun.
 
Kevin Dean said:
I personally like airlocks much better. So much so that I'm going to have to get a "huge" fermenter in order to do wheat beers without a blowoff tube. I just can't manage to keep the blowoff water "clean" long enough. Nasty stuff starts building up overnight and swapping that out every other night is no fun.

That's why you use sanitizer solution instead of water. Even if it is water, I highly doubt anything would climb up into the fermenter. Even moreso if its primary with all that co2 pushing out...
 
I switch to a blow off tube when I rack onto prexisting yeast, although I have never had any trouble really.

I did have trouble with my Cider though, as the carboys were really full. The one airlock filled with overflow. I never bothered to swap it out for over a week. Fruit flies were buzzing around and everything. It is fine :D.
 
Something about an airlock just seems more sanitary-but I could just be neurotic. I use a 6 and a 6.5 gallon carboy and haven't needed a blowoff tube yet-so I've just gone with airlocks.
 
I usually swap out from the blow off to a bubbler at day 3 or 4 as the krausen starts falling because even when I use sanitizer in the receiving bucket, it starts getting cruddy (especially if I had krausen blow off). At this point, running some hot water through the hose is enough to clean it. When I've left it for 10-14 days, water isn't enough and it's a PITA.
 
BrewDey said:
Something about an airlock just seems more sanitary-but I could just be neurotic. I use a 6 and a 6.5 gallon carboy and haven't needed a blowoff tube yet-so I've just gone with airlocks.

Famous last words.... before the ceiling staining explosion.
 
You have just asked one of the most debatable questions in homebrewing my friend. Some argue that blowoff is the only way to go because you want to get rid of all that crud. Others argue you want it in your beer through fermentation...etc, etc.. Do what works for you.
 
I'm a newb so I just want to make sure I don't make a wort bomb. I'll be starting with extract brews using a 6.5 gallon pail carboy so I think I'll start with a airlock and if the airlock starts to get cruddy I'll move to a tube.
 
goswell said:
I'm a newb so I just want to make sure I don't make a wort bomb. I'll be starting with extract brews using a 6.5 gallon pail carboy so I think I'll start with a airlock and if the airlock starts to get cruddy I'll move to a tube.

I'd recommend a 3-piece airlock. Get about three feet of tubing that will slip over the end of the center piece. That way, if you do start to have a blow-off you can make a quick B/O tube that way and not have to scramble around trying to find something that works.
 
soulive said:
That's why you use sanitizer solution instead of water. Even if it is water, I highly doubt anything would climb up into the fermenter. Even moreso if its primary with all that co2 pushing out...

I've never used anything shy of Star San solution. Even then, after a vigorous ferment there's enough crud in the bottle to be a wonderful meal for some molds. I considered using bleach water in there until my last batch (a hefe) when the Better Bottle actually began deforming because of the temperature change (it's 68 in January here for crying out loud!) and pulled a lot of that nasty water upwards. I'm not sure if I got suckback or not but so far the beer smells and looks good so I may have avoided an infected batch.

That said - I don't like blowoff tubes for my brewery. :)
 
Here's the thing about using a bubbler "until" there's a problem. I suppose noobs do watch their fermenter like a hawk, checking on it every hour or so. Once you get over the initial awe of the process, you tend to ignore the thing for a week.

This is not about wanting your krausen to overflow to remove it. It's about krausen that wants to leave your primary whether you like it or not.

This isn't a problem as much for folks that impliment very tight temp control because wild ferments mostly happen when the temp runs away on you (or you pitch a huge starter/yeast cake).

It's a lot easier to rig a blow off every time because it just doesn't get clogged. All it takes is one clogged bubbler and you'll agree with me.

Side note; if you're getting that much of a vaccum pulled in your primary, so much so that you're able to suck the blowoff water all the way in, you've pitched way too warm. I can see pitching at 75 for a 68F ferment target but that's not going to pull 12" of water.
 
Blow Off Tube for me for the first few days in the Primary. Then, when the Krausen settles down, it's an air lock. Speaking of an air lock, I wonder if this weekend's Batch is ready for that... Let me check...
 
I use a blow off tube for primary and an airlock for the secondary.

I like the blow off tube because of the cool bubble pop at the other end ;)
 
Bobby_M said:
I can see pitching at 75 for a 68F ferment target but that's not going to pull 12" of water.

I've got a small apartment and no thermostat. I seriously understand the need to control my fermentation temps but that said, there's only so much a man can do when he doesn't have the space to use a ice-bottle bath and can't set the thermostat below 82 degrees because your illiterate neighbor doesn't understand that the thermostat should be set on what you WANT it, not what you would need it to be to have it where you want it in the next 45 to 60 seconds.

And it sucked about 18 inches of water up,. not 12. :)

Again, I fully recognize I've got temp control issues - but I can also sleep comfortable at night with the belief that I'M NOT ALONE. So I say NO to blow-off tubes - with full disclosure. :)
 
Im doing my first batch right now and I have a few questions.

This is my setup and what I brewed.

Im brewing a hefeweizen in a 6.6 gallon carboy. I used the wyeast 3068 and its fermenting at 68-72F.

I was told by my local brew store to run a dual air release system. I have a cap on my carboy with an airlock and a tube running into a jar of water.

Well the yeast was super aggressive and within 24 hours the airlock became clogged and its bubbling like crazy in the jar.

After reading this thread my question is this. Should I not have used the airlock at all for brewing a wheat beer? And also should I not use both at the same time?

Its now day 2, also do I have to worry about introducing air while cleaning out the jar if it becomes a mess, and if I removed the airlock, capped it, while cleaning that out.

I will insert a pic when I get home if necessary.

Any suggestions?

Thanks in advance.
 
darkstar145 said:
Im doing my first batch right now and I have a few questions.

This is my setup and what I brewed.

Im brewing a hefeweizen in a 6.6 gallon carboy. I used the wyeast 3068 and its fermenting at 68-72F.

I was told by my local brew store to run a dual air release system. I have a cap on my carboy with an airlock and a tube running into a jar of water.

Well the yeast was super aggressive and within 24 hours the airlock became clogged and its bubbling like crazy in the jar.

After reading this thread my question is this. Should I not have used the airlock at all for brewing a wheat beer? And also should I not use both at the same time?

Its now day 2, also do I have to worry about introducing air while cleaning out the jar if it becomes a mess, and if I removed the airlock, capped it, while cleaning that out.

I will insert a pic when I get home if necessary.

Any suggestions?

Thanks in advance.

With an active fermentation going on you don't have much to worry about. Just do what you've got to do. Even in the unlikely event that some wild yeast get in you'll still be OK.

Both an airlock and blowoff together seems redundant to me.
 
abracadabra said:
With an active fermentation going on you don't have much to worry about. Just do what you've got to do. Even in the unlikely event that some wild yeast get in you'll still be OK.

Both an airlock and blowoff together seems redundant to me.

It seems redundant, although the guy at the homebrew store said that it was more or less a back up just in case the airlock became clogged. He mentioned that this may happend brewing this recipe.

I am thinking the airlock may have been just a waste of money. Why have one when a tube and a jar of water works with no problems?
 
to help with airlock clogging, I dremeled off the little strainer piece on the bottom of my 3 piece ones.
 
Olive Drab said:
to help with airlock clogging, I dremeled off the little strainer piece on the bottom of my 3 piece ones.

would you suggest I remove and clean the airlock and cap it off, and just leave the blow off tube, but replace the water with sanatizer?
 
I got in the habit of using a blow-off tube every time for primaries, then switching to the fermentation locks for secondaries. I recall reading many years ago (like 15-20 yrs) that by letting the krausen blow off, it would take with it some nasty bits that could create off flavors. I can't though really think of what those nasty bits might be. Hop bits, cold or hot break? I don't really see them as potential off flavor creators. Maybe this was suggested because the quality of ingredients was suspect back then.

Anyway, now I highly recomend the use of Fermcap-S to reduce foaming. I can fill my 5 gal carboys quite full and now just use an airlock, no more blow off. I might get 1" of krausen but that's it. I'm just now drinking the 1st beer where I used Fermcap and it is quite tasty! I just transferred my Marzen to secondary and it tasted quite delightful.
 
Here are pictures of what I am talking about.


Before

IMG_3696.jpg



18 hours After

IMG_3706.jpg


IMG_3708.jpg


IMG_3707.jpg
 
pjj2ba said:
I got in the habit of using a blow-off tube every time for primaries, then switching to the fermentation locks for secondaries. I recall reading many years ago (like 15-20 yrs) that by letting the krausen blow off, it would take with it some nasty bits that could create off flavors. I can't though really think of what those nasty bits might be. Hop bits, cold or hot break? I don't really see them as potential off flavor creators. Maybe this was suggested because the quality of ingredients was suspect back then.

Anyway, now I highly recomend the use of Fermcap-S to reduce foaming. I can fill my 5 gal carboys quite full and now just use an airlock, no more blow off. I might get 1" of krausen but that's it. I'm just now drinking the 1st beer where I used Fermcap and it is quite tasty! I just transferred my Marzen to secondary and it tasted quite delightful.

Im not quite sure I want to put any chemicals in my beer....but its my first batch and I am learning.


FYI if you didnt know or would like to, here is info on the chemical that is in Fermcap-S Dimethylpolysiloxane

http://www.inchem.org/documents/jecfa/jecmono/v06je42.htm

you can also read about it in wiki, just google it.

Thanks for the advice though
 
darkstar145 said:
Im not quite sure I want to put any chemicals in my beer....but its my first batch and I am learning.


FYI if you didnt know or would like to, here is info on the chemical that is in Fermcap-S Dimethylpolysiloxane

http://www.inchem.org/documents/jecfa/jecmono/v06je42.htm

you can also read about it in wiki, just google it.

Thanks for the advice though

I don't have any problem with using it. It is non-soluble and settles out and does not end up in the final product. Even if there was some that made it into the beer, according to the information in the link you provided, 90% is going to go right through me, and not in my urine although a small percentage might leave that way too.
 
please look at the pictures on the bottom of page three of this thread and let me know if you suggest I change anything.

It will give you a better idea of what happend, and maybe....other than chemicals you can give some advice.

Thanks
 
Olive Drab said:
to help with airlock clogging, I dremeled off the little strainer piece on the bottom of my 3 piece ones.

Me too on my blowoff airlock. I just put a piece of tubing (maybe 1"diam) over the post on the 3 piece airlock. The thing I like about this setup is I can use it on any kind of fermenter-carboy, bucket, BB. My last porter converted me. Blowoff tube till krausen falls then airlock.
 
darkstar145 said:
It seems redundant, although the guy at the homebrew store said that it was more or less a back up just in case the airlock became clogged.

Well, why not just skip the airlock and just go with the blow off tube?

x2 for cutting off the strainer.
 
darkstar145 said:
would you suggest I remove and clean the airlock and cap it off, and just leave the blow off tube, but replace the water with sanatizer?
with that picture I would plug one hole and use the blow off on the other. no need in my opinion to have two and the path of least resistance will cause the airlock to keep getting filled with krausen. Either or, but not both. Plus, one less thing to clean and sterilize.
I dont believe my carboy caps came with a plug for the large hole so maybe you can take some food grade tubing and attach it to the post in the airlock and leave off the other two pieces for a smaller diameter blow off tube as was suggested above.
I have 3 airlocks so that if it gets filled with "stuff" from below, I just swap a clean one on for the duration. I havent had a blow off yet. I also dont use water or sanitizer in the airlock but cheap vodka or little airline liquor bottles I get while traveling.
 
+1 on skipping the airlock.

With the airlock in place, the blow-off won't funtion as well, as in reallity, you have two blow-offs, the second one being your airlock. Take the tubing off of the port it is on and replace it with the little white cap that should have come with the carboy cap (if the cap is gone just plug it up somehow). Put as large a tube as will fit on the port where the airlock was and you are good to go. When it is done blowing off, replace the tubing with your airlock. That's what I used to do.

The smaller port is there to assist in starting a siphon (if you've got a racking tube through the top port)
 
I had a ceiling staining explosion this year. It was probably due to high temp pitching more than anything else. To alleviate this and the overflow of foam (which now makes me nervous...potential clog), I bought some foam control fermcap plus. In addition I also purchased a wort chiller as I was getting impatient with the ice bath. I also plan on straining the wort to prevent large chunks from clogging the airlock. So hopefully, foam control drops plus a wort chiller plus filtration will shape this noob into a better and more relaxed brewer. Just purchased a 6 gal better bottle and carboy thermometers as well. I'll be keeping a better eye on temperature control during initial fermentation and the later phases as well. Even still, homebrew has made me some incredible ales! I'm hooked!
 
I just posted this in the Extract portion but it fits here as well. I just bought some 3/8" outer 1/4" inner tubing (clear plastic) and was wondering how safe it was to use this as a blowoff tube. I know its a little small for a diameter but it fits directly into the grommeted opening of my ale pail and the bunghole of my carboy. I am brewing a german hefe with wyeast 3068 smack pack. thanks!
 
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