The Navien 30028036A Flame Rod is a flame-sensing component designed for compatible Navien tankless water heaters. It works by detecting the presence of a burner flame through electrical conductivity, allowing the control system to confirm proper ignition and maintain safe burner operation. When a flame is not detected, the system can shut down the gas supply to help prevent unsafe co... https://www.partshnc.com/30028036a-navien-tankless-water-heaters-flame-rod