Pressure Relief Valve Leak

[daveafrank]

Had a crazy experience with a sour wort in a keg that I was wondering if anyone could shed some light on.

I am souring 4.5 gallons of wort with lactobacillus plantarum in a 5 gallon corny. Kept it at 95deg for 36 hours and checked it every 12 hours to measure pH. No problems. At 48 hours I went to degas the keg and take a sample...all of a sudden, beer started shooting out of the PRV. I let it settle for a few minutes and tried again. Once again, massive amount of beer loss out of the PRV. Finally I degassed it enough to open the lid and sample the beer. It was quite foamy...apparently that strain of lacto produces CO2.

My question is about the PRV. I've had plenty of foamy kegs...but they've never shot beer 5 feet around the room from the PRV. I've always degassed without issue. Is there something I'm doing wrong here? Was the fact that it was filled close to the top of the keg the main issue? Thank you for any insight.

 

[zachattack]

It sounds to me like the pressure in the keg got high enough for the PRV to vent, and therefore it was doing its job! Overfilling the keg can definitely cause foam or beer to shoot out of the PRV or the "in" post, but even if you filled it properly if the foam reaches up to the PRV it can be quite messy.