Conan

Recipes 

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

cpesko

Recipes 

I agree they take some time to clean.

stunsm

Recipes 

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.

el_horno

Recipes 

How do you monitor fermentation temps in a corny keg?

dinnerstick

Recipes 

i epoxied a thermistor to the outside.

BobTheFourth

Recipes 

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.

E-Mursed

Recipes 

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????

__________________
Schöne Blondine Brauerei
Closed-System Pressurized Fermentation - the future of homebrewing...!!!

“Simplicity is the ultimate sophistication” – Leonardo da Vinci
"A set back is the opportunity to begin again more intelligently" - Henry Ford

What will mess you up the most in life is the picture in your head of how it is supposed to be.
Don’t be upset by the result you didn’t get with the work you didn’t do.
Contrary to popular opinion, no one owes you anything.

dinnerstick

Recipes 

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)
http://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.

mjohnson

Recipes 

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.

patthebrewer

Recipes 

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.

__________________
Custom Hand Crafted Wood Working for Brewers by a Brewer

Predfam@Live.com

"Everybody's got to believe in something, I believe I'll have another Beer" W.C. Fields