TYPE CRDA - DOMED POWER ROOF VENTILATORS, UL705
Power Roof Spun Aluminum Ventilators of Type CRDA as manufactured by ILG Industries meet UL Standard UL705 - E39944 and bear the AMCA Certified Ratings Seal for air and sound performance ( AMCA Publication 211 and AMCA Publication 311). Base and venturi inlet are one piece heavy gauge spun galvanized steel, with wheel and venturi overlapping for efficient operation. Positively cooled motor compartment with forced air ventilation is of heavy gauge spun aluminum construction and easily removable for access to motor and drive. Drive mechanism is of the direct-drive design. The line bore hub is mounted onto the back-plate of the centrifugal wheel. The centrifugal wheel is of heavy gauge aluminum with backward-inclined, non-overloading blades, with wheel balance weights and it is computer balanced. Motor are of open drip-proof construction, NEMA design B. ½” galvanized mesh birdscreen prevents entry of birds or other potentially damaging objects. Optional variable speed control on some models allows for field adjustment and system balance. Motor is mounted with the shaft down to allow easy access to the electrical terminal board/circuit box. Neoprene vibration isolators to reduce noise and wear are standard. Factory run and tested prior to shipment for dependable operation. All CRDA fans comply with AMCA Publication 211 and AMCA Publication 311 and with the requirements of the AMCA Certified Ratings Program.
Prefabricated Roof Curbs: Insulated roof curbs with weather-resistant continuous welded construction. Available with treated wood nailer, aluminum, or galv. steel construction, 8”, 12”, or 24” high; with dam[per shelf and accordingly pitched to meet roof profile.
Special Motors: ALL SINGLE PHASE UNITS COME WITH OPEN DRIP PROOF MOTORS AS STANDARD AND HAVE BUILT IN THERMAL OVERLOAD PROTECTION . Two-speed, totally enclosed, energy efficient and explosion-proof motors for hazardous locations are available. Motor requirements may affect UL Listing.
Backdraft Dampers: Gravity, or motor operated aluminum back-draft dampers are available.
Safety Disconnects: Safety disconnects to cut power to motor for servicing of unit, available as plug-in internal NEMA1 disconnect, or external NEMA3R/NEMA4 disconnect.
Protective Coatings: Fan units are not recommended for exhausting air of a corrosive nature. However, special protective coatings are available where units may be exposed to corrosive exterior conditions. Parts requiring painting are processed through the American Coolair five-stage pretreatment system prior to the application of any coatings to insure maximum finish adhesion. These parts use a thermosetting epoxy powder paint with an average thickness of 3 mils and baked at 400°F to a smooth, hard continuous finish.
Roof Handle: Aluminum handle facilitates removal of roof.
Variable Speed Controller: ILG Tri_Tronic Speed Controller is available on most single phase units.
ADDITIONAL ACCESSORIES INCLUDE: BURGLAR BARS, TREATED WOOD NAILER, ALL ALUMINUM CONSTRUCTION, ETC. EPOXY COATED FANS WILL HAVE 3 MIL EPOXY PAINT WILL BE APPLIED TO ALL METAL SURFACES-INTERIOR AND EXTERIOR. STANDARD COLOR WILL BE COOLAIR'S TRANSFORMER GREEN. OTHER COLORS ARE AVAILABLE UPON REQUEST.