2025 Rinnai Tankless SENSEI RX Series Lineup Rinnai organizes its condensing tankless water heaters by efficiency and built-in features: • RXP Models (Built-in Pump): Includes models like the RXP199iN and RXP160iN. • RX Models (Standard Condensing): Includes models like the RX199iN, RX180iN, RX160iN, and RX130iN. These provide high-flow, continuous hot water with up to 0.98 UEF without a built-in pump. • RUS Models: Entry-level condensing models (such as the RUS75e and RUS65e) rated at 0.90 UEF. • RUCS Models: Compact indoor condensing options (such as RUCS75i and RUCS65i) rated at 0.85 UEF