The Rinnai 109000749 Bypass Filter Set Crossover Mode Sensei manages water flow through the designated bypass and filtration connections in compatible tankless water heater systems. This filter set is designed to connect with the crossover assembly, directing water through the appropriate passages according to the system configuration. Its components support proper water routing and m... https://www.hnkparts.com/109000749-rennai-bypass-filter-set-crossover-mo/4-109000749.html