www.pmmag.com/articles/88879-webstone-p-s-purge-tee
        
        
        Webstone P/S Purge Tee
May 1, 2005
        
Webstone introduces its Primary/Secondary Purge Tee as a solution for hydronic systems when installing secondary loops. This valve allows easy power purging off the secondary loop. It removes air from the system and has a specially designed flow chamber, which allows virtually zero pressure drop.