The prefabricated commercial water heater system from Noritz America combines commercial-grade tankless units with system controllers, manifolds and accessories. Thirty-six rack models are available, specifically designed for the commercial Energy Star certified NCC199 (GQ-C3257WZ US) Condensing Tankless Water Heater Series. With a thermal efficiency of 94 percent DV (95 percent O.D.) the model offers inputs from 16,000 Btu/h to 199,000 Btu/h and a maximum flow rate up to 11.1 gpm. 714/433-2905; www.noritz.com.