One Model, Anywhere: This Rinnai tankless water heater is installable indoors or outdoors thanks to our new Versa Vent and powered by either propane or natural gas thanks to a Smart Sense gas control system; RX-OVC vent cap required for outdoor install Super High Efficiency for Lower Energy Costs: Boasting an impressive thermal efficiency rating of 97%, this tankless water heater optimizes energy usage, helping to significantly reduce operational costs Installation Flexibility with Conversion Kit: This model provides installation flexibility with an optional conversion kit for recirculation; With the kit, users can improve hot water management, optimizing efficiency and saving energy Smart Connect for Effortless Monitoring and Management: Easily set up, manage, and troubleshoot your tankless water heater through the Rinnai Central App on your smartphone User-Friendly Features: Equipped with Smart Connect via Bluetooth for easy setup and management through the Rinnai Central App, plus a quick flush system for simple maintenance. Professional installation is recommended for best results