2013 Rinnai Tankless Series from • RU Series (Super High-Efficiency Plus): Condensing units like the RU160 and RU199 introduced high-grade energy efficiency, dual venting options (concentric or PVC/CPVC), and Circ-Logic technology for programmable external pump recirculation. • Ultra Series (RC / RUC): High-end condensing models (such as the RC98 / RC80 equivalents) providing high maximum BTUs (up to 199,000 BTU) and high flow rates for larger multi-bath homes. • V-Series & Value/Luxury Series: Non-condensing baseline units (such as the V53 and V75 series) designed as compact, wall-mounted, cost-effective solutions for small-to-medium residential spaces