All our indoor sections are available for roof mounted air handlers. In addition, dedicated outdoor economizers are also available. Special consideration has been taken to ensure waterproofing; including, but not limited to, sloped roof, screws with gaskets, guttering, etc. An industrial polyurethane copolymer coating is applied to all exterior surfaces.
Outdoor units’ roof panels are mechanically sealed with capped standing seams. Cap strips are turned down and fastened on both sides and include slimmed profiles to allow water runoff. The roof is sloped a minimum of ¼ in./ft. to ensure rain and snow runoff. The roof system is designed for 30 lbs./ft.2 snow load.
Roof curbs are built and assembled in sections and bolted in the field. Curbs are constructed from heavy gauge galvanized steel. Nailer strips, gasketing, insulation, and counter flashing have to be provided and installed by the contractor.
This section provides a means of modulating the fresh, return and exhaust air volumes. A design is illustrated in figure 30. Contact your Racan Carrier representative for other possible economizer arrangements.
As standard, the fresh air intake includes birdscreen. When the face velocity is a concern, optional aluminum filters can be provided as moisture eliminators. The lateral exhausts include motorized dampers and exhaust hoods on the exterior. Internal motorized low leakage mixing dampers are provided within the unit.
The return and fresh airflow streams are oriented towards each other to minimize air stratification.
However, air blender sections are recommended to further reduce air stratification.
AgION™ Antimicrobial Coated
Steel Liners and Floor Surface
AgIONTM coated metal offers the possibility of suppressing the growth of microbes on the large inside surfaces of the air handlers. While this innovative option does not replace routine cleaning, the coating can be an effective tool in buildings such as schools, hospitals and nursing homes where there is heightened concern about microbial growth. By selecting this option, the air handler liners, standard 16 gauge floor and T-mullions shall have a visible blue AgIONTM coating.
UV-C Germicidal Lamps
As an option, UV-C germicidal lamps can be provided and installed downstream of cooling coil sections. The high output UV-C energy from the UV-C lamps attacks targeted fungus, mold, bacteria or virus at the cellular level, preventing replication and causing cell death. Byproducts are harmless amounts of CO2 and water. These new Carrier HVAC duty UV-C accessory germicidal lamps are the best form of bio-film source control for HVAC units. The lamps are generally installed 1 foot away from the target (downstream of the coil surface) and require 10 square feet of target surface per lamp.