The case of the disappearing fermentation gas

[balrog]

I'll try General, but this could be Fermentation or Kegging.

I'm doing 4.5gal Yoopers Pale in a keg with a Williams TopDraw. This is the 3rd time for this recipe and setup.

I am taking gas out to liquid in on a 2.5, gas out of that to liquid in of another 2.5, then gas out to jug-o-starsan. This is the 22 time I've made this recipe, WY1450, 64F, so I am used to what it does, always make starters, always "goes" within a day. I have fermented in this very keg, this recipe, twice before, purging an empty keg with the fermentation gas. This time I'm using two 2.5 to be purged for various reasons instead of the one 5g keg.

But here I am on Day 4. And while I see humidity buildup in the line from fermkeg to first 2.5, I have NO pressure when checking PRVs of any of the kegs--not the fermkeg, nor either 2.5, nor bubbles in jug. 'Tis really odd. Nice fluffy krausen when I broke down and opened the ferm keg to peek. I don't get it. The beer gods are messing with me.

 

[Carolina_Matt]

My process isn't the same. I ferment in a keg, set up a blow-off tube and put that into a growler with some Starsan. When bubbling is once per second (about 3-4 days in), I put on the gas-in post and set up a spunding valve.

A few times - including my last batch - the spunding valve didn't budge. That happened even though I knew fermentation was still going on. Every time it's happened, the problem has been a leak in the beer-in post or a leak in the lid.

 

[balrog]

Yeah, last time I fermed and served same keg. It was fine, but the drooping top draw hose started stirring up the sediment for the last whole gallon or so, which kinda negated having the whole top draw in the first place. So this time I was going to xfr. But not if the recipient kegs don't get purged.

 

[McKnuckle]

In the spirit of helping, I'll reveal the embarrassing oversights from my last keg fermenting/purging experience.

First, I discovered very early on, thank goodness, that I had not one, but BOTH poppets on the fermenter keg installed upside down, with the O-ring facing down. It was a slow leak from the gas post that only showed up once pressure built a little bit.

I discovered that the liquid poppet was upside down only when I hooked up a party tap to grab a hydro sample. I had to vent pressure to fix that one.

Then when transferring beer, the MFL barb on the liquid line began dripping at the fermenter liquid post. I tightened it urgently, but it simply would not seal. I had to remove the line, replace it, and start over.

My point is to check your gas line hose clamps, MFL connections if applicable, etc.

 

[balrog]

Good idea and easy enough to take first gasout off fermkeg and snap onto CO2 tank to ensure I can blow all the way through system to jug-o-san.

 

[Vale71]

Congratulations, you have a leak. Now finding it among all that interconnected hardware is going to be tons of fun...

 

[balrog]

Ah, it's what we hobbyistst do for fun, eh?