New to forum, so forgive me if I immediately broke every form of forum etiquette. I decided to take the plunge into pressure fermentation. I made a fancy contraption that my friends said I would be greedy not to share with the world. My setup might be pretty straight forward, but I haven't seen many people sharing the whole rig in action.
-It's a typical pin lock 5 gal keg, full length dip tube.
-Stubby cobra tap for taking gravity readings. Yadda yadda...
So coming from the gas out:
-Gas connection leading to more than enough hosing.
-Connects to a pool filter with a spare piece of 1/2" silicon tubing.
-Homemade spunding valve made from cross fitting, pressure gauge and adjustable release valve.
-The 4th connection on the cross leads to a shutoff/check valve that connects to a hose and gas connection.
Why the second gas connection you ask? WHY NOT. No it's so I can carbonate a second keg with the pressure if I wanted. I haven't tried it, but it'll work in theory right??? I don't plan on fully carbonating with it, but I suppose anything helps.
The whole thing was pretty straight forward to construct. The few problems I ran into were:
-I used an oil filled gauge, which is excessive and I suspect is giving me incorrect readings.
-The pool filter is plastic so I used extreme care when threading onto it.
-The check/shutoff valve had issues threading onto the brass cross. Is there something I don't know? I noticed the system had a leak and so I submerged the thing under water and looked for the bubbles. BAM, it was the damn check valve, I added more tape and cranked down on it. Fixed.
The hoses are all barbed to the standard flare thread, easy cleaning. The pool filter conveniently uses NPT for the two connections and has a nice little ring mount for the filter that the 1/2" tubing fits snuggly into. The silicon tubing isn't really necessary, or even at all. But I had less than a foot of expensive 1/2" silicon tubing I couldn't bring myself to toss out. I also could fill it with liquid and use it as an airlock?
First run. I brewed a batch smaller than normal and filled the keg to a few inches below the gas tube. I've encountered almost no blow off. The only blowoff material I saw was when I was skeptical that it was even fermenting so I cranked up the pressure. Built to nearly 20PSI, I panicked and released it down to about 5psi, in the process it spat some foam out the gas tube, oops but no big deal. I think the next I'll be less conservative with headspace.
Questions I have:
-I've seen a handful of pressures and regimes that people use. Input?
-I've seen people increase pressure as fermentation progressed. Should I change pressure in proportion to gravity changes?
-If it gets hotter, should I compensate with more pressure?
-Is there such a thing as too much pressure? Physical limitations aside.