When to Use Blow Off Tube?

Hi. I've got a question about when to use a blow off tube.

I'm 3 days into my first batch, a Belgian triple using Wyeast 1762 Belgian Abby Ale 11. The brew is fermenting like crazy in the 6.5 gallon glass carboy. In fact fermentation is so good the airlock is oozing krausen pretty regularly. i want to avoid a beer explosion! At what point do you recommend I take out the airlock and switch to a blow off tube? Or should I instead just take the airlock out, rinse it, sanitize it and stick it back in?

Thanks for your help!

If its already oozing krausen. I would go ahead and put a blowoff tube on there.

About two days ago would have been good. I usually use a blow off tube for every beer. I had an explosion once and I had to clean the floor walls and ceiling.

I had my first explosion recently, when the krausen starts climbing the walls of the carboy, I just put the tube on. Fortunately I ferment in a chest freezer so when it made a mess. I didn't have to clean the ceiling. The krausen will eventually clog up the airlock and the pressure will force it off the bottle.

nukonamo said:

About two days ago would have been good.

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exactly.

if it is oozing, be careful taking off the airlock! Mine blew all over when I twisted the stopper off. Was surprised how much pressure there was. Cover with a clean cloth as you pull the airlock just in case.

I alway put my blow off tube on for the first cup couple of days. The only time that I do not is when I'm brewing less then a 5 gallon batch

Yup, me too. I ALWAYS start with a blow-off tube. I get extremely vigorous fermentations, as a rule. The first time I used Fermcap-S, I figured I wouldn't need to use a blow-off tube anymore. As I was walking away, I had a nagging doubt about it and put one on anyway. When I woke up in the morning after a dead solid night's sleep (exhausted after a long evening of brewing) the foam was pumping through that thing like crazy. Lucky. All it would take is one explosion in our closet and SWMBO would NEVER permit fermenting beer in the house again (and I wouldn't blame her).

The only time I've used a blow off tube was while I was making my first hard cider. I think I over pitched, either way, I was swapping airlocks out every 4 hours or so, so I finally said screw it. I didn't have a hose wide enough for the mouth of my carboy, so I took my 3/8'' hose that came with my kit, shoved it in my 3 piece airlock and ran it down into a clean beer bottle with star san in it and wrapped it all up tight with tin foil. It was fun listening to it bubble so hard it sounded like pops.

I uae a blow off on everything I brew. Why take chances?

Now would be a good time. And as OkashiiBrew suggested, cover the opening with a cloth as you slowly and carefully remove the airlock. Put the blowoff tube in place, and put the other end into a bowl or bucket of clean water.

thanks to every one of you for the tips, very helpful. I switched to the blow off hose and it worked perfectly. Today I switched to the secondary fermentor (after 7 days in primary) with an airlock. So far so good!

I had an explosion even with the blow-off tube. Now I use an airlock, but just set the bucket lid on loose, with a little weight to hold it in place. After a few days, I check the bottom of the airlock and snap the lid down. It can still run over the top, but it won't be violent.

I just had my first explosion, wish i had read through this before. So now of course I'm gonna use a blow-off tube from now on.

My only concern is that I work out of town a lot. Do y'all see any issue with the sanitized water in the pitcher getting contaminated if the krausen leaks into it while I'm gone? I'm gone for a week or 2 at a time.

2 times in 2 weeks. This newest batch has a starsan washcloth over the airlock and is in the guest room shower. Will keep the airlock on loose like ncbrewer's lid so the sanitized washcloth will cover the carboy if it pops. If it is really bad, I can run the shower with the hand held sprayer and clean up. Great way to cool down a hot fermentation quickly, or heat up a stalled fermentation too... maybe....

BobBailey said:

I uae a blow off on everything I brew. Why take chances?

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+1 - since I started using 6 gallon Better Bottles. I could get away without them in my old glass carboys.

I've only ever used an airlock and use a 6.5g bucket for 5g batches, but my next recipe (EdWorts Robust Porter) highly recommends a blowoff tube.

Is this an issue with 1.5g of headspace in the bucket, or should I definitely use a B. Tube? Also, since the bucket only has a very small hole for the airlock, probably 1/4" dia., how could I possibly fit in a big enough tube?

I always start with a blow off tube. After all is is just another form of an airlock.

Out of all the batches I have brewed, not many blew off. There is mo way to predict it. I have had a high gravity brew just slowly chug along. On the other hand, had a low gravity brew blow off like crazy.

Each fermentation is different so I figure a blow off tube is easier than mopping the ceiling.

ncbrewer said:

I had an explosion even with the blow-off tube. Now I use an airlock, but just set the bucket lid on loose, with a little weight to hold it in place. After a few days, I check the bottom of the airlock and snap the lid down. It can still run over the top, but it won't be violent.

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What size tube did you use? Your using a bucket so you only can get about 5/16 inch size tube? or did you attach a tube to the airlock? I just started using a carboy and the 1 inch tube is nice for a blow-off.

jonmohno said:

What size tube did you use? Your using a bucket so you only can get about 5/16 inch size tube? or did you attach a tube to the airlock? I just started using a carboy and the 1 inch tube is nice for a blow-off.

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Yeah, this is what I really can't figure out? And if you attach a tub to the airlock, won't the whole apparatus still be limited by the smallest diameter? If it clogs at the connection between airlock/bucket, won't I still have the issue of the airlock exploding off, taking the blowoff tube with it?

I guess there is the bucket method of loosely attaching the lid and putting a light weight on it...

LowNotes said:

Yeah, this is what I really can't figure out? And if you attach a tub to the airlock, won't the whole apparatus still be limited by the smallest diameter? If it clogs at the connection between airlock/bucket, won't I still have the issue of the airlock exploding off, taking the blowoff tube with it?

I guess there is the bucket method of loosely attaching the lid and putting a light weight on it...

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I would drill out the hole in the lid and get a couple of bungs. One to fit the blowofff and one to fit the airlock.

Bob

BobBailey said:

I would drill out the hole in the lid and get a couple of bungs. One to fit the blowofff and one to fit the airlock.

Bob

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Well I'll be...that is so crazy it just might work! In fact, if I drill it out to the same diameter as a carboy, I could use the carboy bungs (which I already have) for the airlock, and I would only need a bung for the blowoff tube...well, and of course I need to buy the tube also.

Thanks!

I have a 1" blowoff tube, but I can't use it. It's too small to just jam into the neck of the carboy (i.e., it leaves a gap). I can stick it in an airlock body and attach the airlock to the carboy with a drilled stopper, but the 1" tube is so rigid that it causes the stopper to keep popping off the carboy. That is, the tube has a coiled shape it tries to keep, which applies torquing or pulling force on the airlock/stopper it's connected to, and the whole thing won't stay in the neck of the carboy. Anyone have a solution for this?

Local hardware store (TruValue) bought tubing for $0.45 a foot. Now its not 1" but you could probably buy some tubing cheap like this.

jonmohno said:

What size tube did you use? Your using a bucket so you only can get about 5/16 inch size tube? or did you attach a tube to the airlock? I just started using a carboy and the 1 inch tube is nice for a blow-off.

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I was using a carboy at the time. I think it was a 5/16" tube stuck into a hole in the stopper. After that I started using a 1" tube, and now just leave the lid on loose. I never liked the way the big tube got gunky looking when it released kraeusen.