The NCC1991 condensing tankless water heater from Noritz America delivers a thermal efficiency of 95 percent, using natural gas, with an input range of 16,000 to 199,900 BTU. This enables the unit to meet the hot water needs of larger residential applications, as well as a wide variety of commercial projects. The NCC1991 is the Low NOx version of Noritz’s NCC199 condensing tankless unit.
Using a special Quick Connect cable, two NCC1991-DV units can be coupled to provide an input of nearly 400,000 BTU, with a turndown ratio of more than 36 to 1. Up to 24 units can be combined into a single system, making the NCC1991 ideal for applications where hot water demand can vary substantially over the course of a day or throughout the year.
To obtain its 95-percent efficiency level (97 percent with propane), the NCC1991 uses a secondary heat exchanger, made entirely of stainless steel, to capture residual heat from the unit’s exhaust to preheat incoming water before it enters the main copper heat exchanger. This heat recovery process lowers the temperature of the flue gases, allowing an additional, cost-savings benefit: exhaust vent runs with less expensive, installer-friendly PVC piping rather than the stainless steel venting required by conventional tankless water heaters.
Other key features include:
- Commercial grade heat exchanger delivers enhanced performance and longevity, making it ideal for heavy use and commercial applications.
- Space savings: The powerful, wall-hung NCC1991 requires less than 3 feet of wall space and takes up no floor space. Weighing only 66 pounds, the unit can be mounted inside or outside on a wall or on a free-standing rack.
- Stainless steel casing allows the unit to be cleaned, sanitized and protected from its surroundings, whether located indoors or outside.
- Full diagnostics ensure easy maintenance and repair. In fact, most parts of the heater can be replaced and are plug-and-play for quick repairs.