Beer Forum

Pushing beer from one keg through a plate filter to another keg. No bubbles on the input side, but as the beer exits the plate filter, both of the stems are filled with bubbles and the beer is bubbling in the target keg. Clamped down all the connections but no change. Are the bubbles actually O2 that has bled in or the C02 from the process? Is this something I need to worry about?

If there is no beer dripping out from between the plates, I'd guess CO2 in solution is coming out. Chill the beer and the filter housing to keep that under control. Higher pressure might help too - rather than 0 psi on the receiving and 3psi on the sending, try 10psi sending and 7psi receiving.

This happens to me as well. I always assumed it was CO2 coming out of solution from all the nucleation points in the filter pads. Also, the whole system is under positive pressure too, so if anything, beer and CO2 would leak out from any loose seams, not draw air in.