The Navien 30004827B Cold Water Inlet Adapter is a replacement plumbing component designed for compatible Navien tankless water heaters. It provides a secure connection for the incoming cold water supply, directing water into the unit's internal heating circuit for on-demand heating. This adapter helps maintain proper water flow and reliable connections between the plumbing system and... https://www.partshnc.com/30004827b-navien-tankless-water-heaters-inlet-adapter