Noritz NRC98 DV Condensing Tankless Water Heater. The ENERGY STAR rated NRC98 DV, Noritz's brand new ultra‐high efficient condensing model, demonstrates its ongoing commitment to the green movement by expanding its newest tankless water heater product line: the ecoTOUGH Series of high efficiency, easy‐to‐install, gas‐fired condensing tankless water heaters. Tankless Water Heater Condensing Ultra-Low NOx Indoor The GTS-540-NIH tankless water heater uses up to 199,000 BTU/hr of natural gas to deliver an endless supply of hot water for a 3 bath home in northern climates and up to a 4 bath home in southern climates (one shower head per bath). Utilizing condensing technology, this heater is extremely efficient with a Uniform Energy Factor of 0.93. Tankless Water Heater Non-Condensing Ultra-Low NOx The ATI-510U tankless water heater uses up to 199,000 BTU/h of natural gas/liquid propane to deliver an endless supply of hot water for a 2.5 bath home in northern climates and up to a 4 bath home in southern climates (one shower head per bath). The ATI-510U has a Uniform Energy Factor of 0.81.
The condensing tankless water heaters feature Ultra-Low NOx condensing technology and all models meet ENERGY STAR® qualifications. Fully modulating, non-condensing gas tankless water heaters feature a sealed combustion and power vented flue. Indoor and outdoor models are available for residential applications.Rinnai RU80EP 8.0 GPM Outdoor Ultra-NOx Condensing Rinnai's condensing tankless water heaters deliver more efficiency than ever before. Available in four models, suitable for mid- to large-sized home.