Nortek Global HVAC Introduces the R7DA Combination DOAS/RTU to its R7 Platform for Light Commercial Spaces

The R7DA fits many existing roof curbs, features one-inch foam-insulated panel cabinet along with dozens of highly-configurable options for optimum IAQ and space comfort.

ST. LOUIS, (March 27, 2019) —Nortek Global HVAC, O’Fallon, Mo., has added the R7DA, a combination dedication outdoor air system (DOAS) and conventional space conditioning rooftop unit (RTU), to the Reznor® and Mammoth® branded R7 Platform product lines for optimum indoor air quality (IAQ) and space comfort in commercial applications.

The low cost R7DA is the industry’s only direct expansion (DX) package DOAS/RTU offering a drop-in replacement that fits many existing RTU brand roof curbs. Its one-inch-thick R-13 foam-insulated panel cabinet and dozens of available highly-configurable options rival custom-built units, but its cost is comparable to off-the-shelf systems.

Its small footprint and low cost solve new construction and retrofit outdoor air compliance challenges for hair/nail salons, small restaurants, retail stores, government buildings and other facilities. The R7DA will help these application types meet the mandates for outdoor air and comply with U.S. Department of Energy (DOE) codes based on ASHRAE 62.1, ASHRAE 90.1, AHRI-920 and other standards.

The R7DA, which is available in 6 and 7.5 tons, complements the R7 Platform’s existing R7TQ package space conditioning (only) unit that’s available from 6 to 12.5 tons. The product line will be expanded to 20 tons in 2019.

The R7DA features a state-of-the-art thermostat interface and DDC controller that provides pinpoint control by modulating EC motor supply fans, air-cooled DX and gas heat. The DDC controller also uses proprietary algorithms to facilitate Nortek’s newly-patented method of modulating hot gas reheat circuits that eliminates inefficient evaporator freezing challenges common among all DOAS brands operating in cold weather.

The R7 Platform’s highly-configurable, field-convertible flexible design adapts to existing horizontal or vertical supply air discharge and return air without incurring the design costs of custom equipment. Electrical and gas piping inlets are possible through the curb or unit.

The industry’s only DOAS with one-inch (25-mm) flame-retardant foam panel construction provides better energy savings, operating noise reduction and superior IAQ versus exposed batt insulation that collects and distributes moisture, dirt, mold and other contaminates throughout a building. The cabinet also features slam-latch door hinges that add structural integrity and quick service access.

The R7DA also features:
• Compatibility with many existing RTU brand curbs eliminates costly roofing repairs during retrofits;
• High performance cabinetry and components, along with features, such as a corrosion-proof reinforced carbon fiber condensate drain pan and optional coil coatings for seacoast applications, promise long lifecycles of 15 to 20 years and beyond;
• Airflow sensors monitor static pressure to provide optimum CFMs;
• Adapts to most existing building electrical services because it requires minimum current ampacity/maximum overcurrent protection (MCA/MOP);
• Warranty is five years for DX parts and 10 years for the gas heat exchanger.

For more information about Reznor products, visit or call 1-800-695-1901 to find a manufacturer’s representative.