RCB399AN RCB Model Series

Commercial Boiler

Experience the next level in hydronic heating with the RCB•Series™ Wall-Hung and Floor-Standing Boilers from Rinnai, offering superior thermal efficiency and intelligent, user-friendly controls. Choose from multiple models, including wall-hung (RCB301AN, RCB399AN) and floor-standing (RCB500AN, RCB750AN, RCB1000AN) options to fit your space and capacity requirements. Each boiler features a 10:1 turndown ratio, allowing precise adjustments to meet varying demand. Built with a 316L stainless steel water tube heat exchanger for lasting durability. Get the quality you expect from Rinnai backed by a 10-Year (Non-Prorated) on the Heat Exchanger plus 1 year Parts and 1 Year Labor.

  • 97% Thermal Efficiency
  • Warranty 10 Year HEX / 1 Year Parts
  • 39,900 BU / (11.7 kW) (minimum)
    399,000 BU / (117 kW) (maximum)
  • Indoor


iWarranty information is available in the Installation & Owner Manual.