Can I use a Corny Keg as a Primary Fermenter?

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EamusCatuli

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My fermentation chamber can only hold one 5 gallon ale pale, which sucks. However, I have a bunch of corny kegs and I could fit around 3 of them inside it instead. If I purged it everyday, couldn't this work?

Thanks,

Matt
 
Do like this and you will be all set to corny keg as a fermented vessel. No issue with cleaning.

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Fill keg with hot water and scoop of PBW or Oxiclean, let it sit for several hours, rinse with lots of water. Really not difficult to clean at all. Simpler than a slippery glass carboy IMO.
 
I've been experimenting with fermenting in corny kegs and so far I like it. I transfer the wort to the keg after boiling without cooling it, seal it, let it cool down overnight, then pitch the yeast the next day. I use some rubber tubing attached to the gas-out post for a blow off. Once fermentation is complete I transfer to another keg using C02 to avoid exposing it to air/oxidation. This can be accomplished by using a jumper to connect the liquid out posts on both kegs.

No issues so far.
 
During the past year, I fermented around 7 beers in corny kegs and am planning to go back to buckets for 2012 for at least some of my brews.

Downsides:
1. The kegs are a total PITA to clean
2. Trub clogged my dip tubes & disconnects whenever I tried to push beer from fermentors to kegs. Ended up syphoning every time.
(cutting or bending the dip tubs might have helped ... )

Upsides:
1. Easy to move keg in and out of fridge for wort chilling & crash cooling.
2. Like the idea of fermenting in stainless

Good luck!
 
I've been experimenting with fermenting in corny kegs and so far I like it. I transfer the wort to the keg after boiling without cooling it, seal it, let it cool down overnight, then pitch the yeast the next day. I use some rubber tubing attached to the gas-out post for a blow off. Once fermentation is complete I transfer to another keg using C02 to avoid exposing it to air/oxidation. This can be accomplished by using a jumper to connect the liquid out posts on both kegs.

No issues so far.

Guessing the tubing isn't too big, maybe 1/4" id? If so is there risk of krausen clogging it?
 
So it looks like a spare lid drilled and tapped for a fitting for a blow off tube and a small pail of water for an airlock and transfer with an autosiphon when done... I like the sound of that because I too have room for one pail or three/four kegs. I'm not too sure about the direct transfer because of trub without going through a filter of some kind, but an autosiphon doen't create much airation and it will be under pressure soon anyway, May have to give this a try. And BTW a pressure washer and PBW will clean a Corny in no time at all. Then a ****** of Star-san and store till next batch. Just keep a spare set of O-rings handy and a tube of food grade lube and your golden.
Bob
 
I very frequently ferment 3.1 gallons of wheat in a 5 gallon keg. I don't use a blow-off or even an airlock. I just close the lid and let it sit, kind of like a bastardized version of the spunding valve setups found on this board. The only difficulty in cleaning them is when krausen reaches the gas diptube, as there's crannies that need to be scrubbed. They're still easier to clean than a carboy though.
When I transfer to the 3 gallon keg I just hook up a beerpost-beerpost line from the 5 gallon to the 3 gallon and let the fermentation pressure push most of the beer our. After pressure dies off siphoning takes over (the 5 gallon is elevated WRT the 3 gallon). The trub compacts well enough that very little is sucked into the diptube and what does transfer falls out in the kegerator anyway. Kyle
 
I used 5 gallon cornies for about 40 batches, and at this point would recommend against it. I would put about 4.5 gallons (including the yeast starter) into each. Removing the dip tube and poppet from the gas side let me put a large blowoff tube right over the post, and I would inevitably lose about 1/4 gallon in the first day or two from blowoff, and eventually end up with about 4 gallons of finished beer after racking loss. Hop debris often clogged the hole, and led to pressure buildup inside the keg. When your over-pressure valve is also clogged, you will have a hell of a time venting the pressure without getting fermenting beer everywhere. Forget any ideas you might have about using co2 to transfer from primary to secondary (or bottling keg), unless you enjoy cleaning a liquid dip tube full of hop and yeast debris every few minutes. Clean-up time is considerably greater than a carboy due to the increased number of parts, and potential for leaks is always higher. On the upside, the smaller footprint is convenient for situations like yours, and you can get your arm down inside to clean, but cleaning a carboy with something like the "marks keg washer" is infinitely easier.
 
I used 5 gallon cornies for about 40 batches, and at this point would recommend against it. ...

I've been using cornies for about 10 batches now, and haven't experienced a single one of these problems. But I do a few things differently to prevent the issues you've had.

1. I use a hop bag (for boiling and dry hopping), so hops never have a chance to clog the posts, dip tubes or relief valve.

2. I cut the liquid tube 1.25" from the end. Once fermentation has stopped and the yeast has settled out, I get very little trub or yeast being sucked into the liquid tube for transfer, essentially eliminating any chance for clogging. This generally only results in the loss of a couple of ounces or beer. I always use CO2 to transfer under pressure.

3. I use Fermcap to keep blow-off to a minimum. Its not perfect, and sometimes I still get some krausen in the discharge tube, but I've never had a clog of either the gas post or the relief valve. And I just hook the discharge tube (1/4" bevlex) straight to a gas QD, so its not like its a wide-open tube or anything.

4. I check for leaks after filling the keg by pressurizing it. If the lid or posts are leaking, I'd know and can lubricate them or adjust them as necessary.

Regarding cleaning, I just don't think its any more difficult than a carboy. Mark's keg washer works just as well on it once you've taken the posts off. And instead of having to put a cloth inside and madly swirl it around to get tough deposits off, with a keg you just reach in and scrub. Cleaning the posts and dip tubes takes all of 30 seconds with the proper tools.

Regarding temp monitoring, my controller has a steel probe which I attach to the side of the corny with long twist-ties and a bubble wrap pad. I'm not even sure the bubble wrap is necessary though - the thermal connection between the steel probe and steel keg should be a lot stronger than with the surrounding air. I sanity-check that its working properly with those stick-on thermometer strips.
 
Have to agree... If you are having that many problems you are being sloppy and lazy.

Best thing I ever did was selling my carboys.

Cleanest fermentations, ease of use, simple process, more control...what's not to love? Fermcap and pre-filtering of wort make a huge difference, but you should do that with all your beers.

Plugged dip tubes...???? Seriously????
 
agree with bob above. since making a temp-controlled corny my main fermenting chamber i have found it very easy to use and clean. (link to pics)
https://www.homebrewtalk.com/f51/my-ugly-peltier-temp-control-junk-350722/
i generally take out the beer-out diptube and ferment with two gas-in tubes, each with a blowoff. as a backup if one is clogged. but i have never had one clog, even with a lot of blowoff. then i siphon out with a normal auto-siphon. but i also sometimes ferment and transfer under pressure. i carefully bent the dip tube up so it is off the bottom and horizontally positioned. my only complaint is one of volume, but as i am in an apartment and pressed for space, they are great for me. cleanup is simple (unless you're so fat your arm doesn't fit in); disassemble, soak, scrubby pad, rinse. you can blast them with boiling water if you have to. make sure to get the poppets out and clean any gunk in there, and give special attention to the post holes on the keg after you take the posts out, and the weld seam at the top.
 
I've been using cornies for about 10 batches now, and haven't experienced a single one of these problems. But I do a few things differently to prevent the issues you've had.

1. I use a hop bag (for boiling and dry hopping), so hops never have a chance to clog the posts, dip tubes or relief valve.

2. I cut the liquid tube 1.25" from the end. Once fermentation has stopped and the yeast has settled out, I get very little trub or yeast being sucked into the liquid tube for transfer, essentially eliminating any chance for clogging. This generally only results in the loss of a couple of ounces or beer. I always use CO2 to transfer under pressure.

3. I use Fermcap to keep blow-off to a minimum. Its not perfect, and sometimes I still get some krausen in the discharge tube, but I've never had a clog of either the gas post or the relief valve. And I just hook the discharge tube (1/4" bevlex) straight to a gas QD, so its not like its a wide-open tube or anything.

4. I check for leaks after filling the keg by pressurizing it. If the lid or posts are leaking, I'd know and can lubricate them or adjust them as necessary.

Regarding cleaning, I just don't think its any more difficult than a carboy. Mark's keg washer works just as well on it once you've taken the posts off. And instead of having to put a cloth inside and madly swirl it around to get tough deposits off, with a keg you just reach in and scrub. Cleaning the posts and dip tubes takes all of 30 seconds with the proper tools.

Regarding temp monitoring, my controller has a steel probe which I attach to the side of the corny with long twist-ties and a bubble wrap pad. I'm not even sure the bubble wrap is necessary though - the thermal connection between the steel probe and steel keg should be a lot stronger than with the surrounding air. I sanity-check that its working properly with those stick-on thermometer strips.

The only thing I do differently is I just take the gas in post off and worm-clamp a 1/2" vinyl tube on. Never had a clogging problem. I did once have a clog when using a disconnect. That one ended up with beer on the ceiling.

Cleaning is easy with PBW.
 
I've also used corny kegs to ferment before with zero issues...frankly I think they make a pretty good fermenter. Like a steel carboy thats easier to clean and dry hop in. The way I've done it is to remove the post on the liquid side (remove the dip tube) and stretch a blow off tube to the threaded post and your good to go. Now mine has never clogged, but if for some reason yours does you've got gas side to can use for blow off too (or maybe both at once), I've also seen some guys remove the relief valve and jam a bubbler in the hole. I would leave at least one gallon head space. The are also easy to clean. Heck I still use them if I make a larger batch.:)
 
I've never understood the "cornies are hard to clean" thing. They're certainly no worse than a carboy, and I'd say they're a lot better.

I do pressurized fermentations in cornies, and I would never go back to glass or plastic. It is vastly easier this way.
 
Do a search. There are a LOT of threads on this. It's a personal preference...but I can say that cleaning isn't an issue if you have a keg cleaner system and do several kegs at a time.

When fermenting, take out all diptubes and posts and set them aside. Put small stoppers in the diptube holes. Remove the pressure relief valve and insert blowoff. Fermcap will keep the krausen down. When ready to transfer, reinsert diptubes and transfer to a new keg with a liquid jumper. Use swivel fittings on it and you can runoff the first bit of yeast and reconnect to finish transferring.

It really is a slick system...and these fermenters can go back to being kegs if you need the extra capacity. Can't do that with a carboy or bucket. They also retain their value indefinitely....you can sell them for what you paid.
 
I've been picking up kegs pretty cheap and thinking about doing this as well... anyone have any issues the further they got into it? Wondering about high gravity beers and the need for 1" blow off tubes?
 
A number of years ago, I managed to score a pair of 10 gallon cornies that have become my primary fermenters. I have an extra pair of gas posts, one for each keg.

The posts have no poppets; they're just empty bodies. Each post has length of vinyl hose stuck on it as a blow off tube. I fastened wire around the necks of a pair of water bottles that I hook onto the kegs as the blow off tube reservoirs.

I typically brew volumes to put about 8 gallons of wort into the kegs to ferment. I've never has a problem with blow outs of crazy over blows.

Cleaning, as long as you don't let crud dry on, is not a problem. Warm PBW solution is our friend.

I did finally get a bit tired of scrubbing on the krausen ring, though. So, without knowing about "Mark's Keg Washer", I built one of my own. Even with a pump and other parts, I spend well under $40. It does a great job and I don't have to scrub anymore.

https://www.homebrewtalk.com/f51/cheap-easy-keg-corny-washer-449336/

The old carboys are used for cider fermenting. Cider doesn't get light struck, so glass is not a problem.

In short, in my opinion, corny kegs as fermenters are far superior to glass. Any of the negatives presented in this thread are easily overcome.
 
My only worry is clogging or a super active fermentation of the blow off and screwing up the batch. Some articles say corny is 6 gallons but some say 5... I like the idea but having less beer in the end I'd rather stick to buckets really.

Sent from my SGH-T769 using Home Brew mobile app
 
I've been using four pin lock kegs to ferment in for two years - they are wonderful. I take the gas poppet and dip tube out and use vinyl tubing to fit over the gas in port, secure with a tube tie and wham other best carboy ever.

As to the 5 versus 6 gallon, I think they are a bit smaller (closer to 5 gallon), but dry hopping, etc. is so easy. Keg lube is your friend for sealing your fermenter, remember that your beer will be producing CO2 and thereby maintaining positive pressure in the fermenter.
 
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