Keg CO2 Purger & Blowoff Connector

thingiverse

This device enables you to utilize the carbon dioxide produced by fermentation to purge a keg, minimizing oxidation of beer stored in the keg and conserving CO2 in your gas cylinder. Assembled as two parts, this system consists of a lid with two barbs screwed onto a large 2L/2qt jar. The larger pass-through barb allows for connection of 3/8" tubing from a drilled bung to the lid, while the smaller 7/16" barb facilitates gas passage from the jar through 7/16" beverage line to the liquid-in port of your keg. The second part features an angled barb that enables connection of 3/8" tubing to a gas-out connector for an airlock. To use, assemble the jar and all hoses thoroughly sanitizing before assembly. A small amount of plumbers putty or silicone can be applied to ensure a good seal in the lid. Attach the bung to your carboy, bucket, or conical fermenter, then connect the liquid-in connector to your keg. Next, attach the airlock to the gas-port of your keg. CO2 produced during fermentation passes through the jar, capturing blow-off while clean CO2 enters the keg. The air connector/airlock system allows the keg to ventilate while preventing room air from re-entering the keg. A fermentation will produce approximately twenty times the volume of beer in CO2, ensuring thorough purging of your keg. As soon as bubbling slows, disconnect this system and seal your fermenter with a bung + airlock. I recommend using your CO2 system to add 5 PSI of pressure to the keg, maintaining the seal and preventing room air from entering and diluting your CO2. In addition to printed parts, you will need 3/8" and 7/16" ID tubing, a large wide-mouthed canning jar, a 10 mm (or 3/8") hose barb, an airlock, and both gas & liquid connectors for your keg (pinlock or ball-lock). This device could not have been designed without the excellent canner jar lid by AlexEnglish and Hosebarb connectors by Hamano: https://www.thingiverse.com/thing:19105 https://www.thingiverse.com/thing:2362206 Note that Hamano's 10 mm hose barb is perfect for the hose barb required for this system. TheWalrus's Carboy Stopper Clam is a great addition to help keep the bung in place if using a carboy: https://www.thingiverse.com/thing:2519414