Fermenting in a pin lock keg question

I bought a used 3-gallon pin lock keg a couple of months back for use as a primary fermenter (and prob for kegging beer down the road) and so far I've fermented 4 batches in it. Ive been brewing 2.5 gallon batches and at first I was worried that I would have massive blowoff issues due to lack of headspace but so far Ive had the exact opposite. My beers all fermented completely but I never saw a single bubble in the blowoff bucket.

The keg held pressure when I first received it for sure. The only thing I did to it was remove the gas valve poppet so I could use it as a blowoff. So my question is about the valve built into the lid of the pin lock kegs. Is it releasing pressure as well in this scenario? Is a blow off tube really necessary for this setup? Are there advantages to switching to the ball lock style lids with the manual valve?

 

I wonder if you're perhaps not getting a great seal with the lid? Normally you would "set" the seal by giving it a blast of co2. Do you pull up on it before locking the handle down? All that co2 has to be going somewhere...

 

I never really considered the lid seal cause it was a new oring but maybe I should pay more attention to it and try to seal it tighter. For some reason I thought the co2 from the primary would seat it

 

Is it possible the gas out is getting clogged with krausen? That's a pretty small hole for a blow off.

 

Ive never noticed any residue inside the gas valve. I just put a beer in there two days ago and I dont want to mess with it right now but when I take it apart I'll pay closer attention to the valve stem maybe it is getting blocked up.

 

Assuming you are doing something like this setup where you remove the posts, poppets and tubes altogether, else hop debris will clog the poppet and build extreme pressure.

As long as the blow-off valve is screwed in tight and the lid is secure (maybe use some lub), yes, you should see bubbling.

MS


Primary fermenting in a corny by Mad Scientist Brewhaus, on Flickr

 

I removed the tubes from both the liquid and gas sides and the poppet from the gas side but I did not remove the post itself because I didn't think I'd be able to secure the hose to the little nub that's left over.

 

My guess is that you are passing gas out the liquid post side because that tube is removed, no bubbling because of that.

Do you have a spare gas tube you can put on the liquid side during fermentation period?

 

If I tip an unpressurized keg upside down with star san in it, the keg will leak. If liquid can get out then air can. The pressure caused by fermentation isn't likely strong enough to seal it up.

 

Well I don't have a spare per se but I do have the one Im not using on the gas side. Ill try that for my next brew in a couple of weeks when I transfer this one out.

 

your beer fermented completely, did they taste off or something? if not this is a non issue. you probably have some gas seepage, but i doubt that you are getting enough air in to ruin a batch if any at all.

 

I am inclined to agree with you that all in all this is a non issue, which is why I waited until the fourth batch to even ask the question. Im not getting any off flavors and it's not like Im using co2 to transfer out of the keg so there will be exposure to oxygen anyway. Really I was just curious because Ive read so many people talking about using Fermcap to keep the primary fermentation under control.