The damper is opened by air pressure differential and closed by gravity. Standard models include adjustable counterbalance weights to assist closing. Ratings (See page 2 for specific limitations) Pressure: 2.5 in. wg (622 Pa) - differential pressure Velocity: 2000 fpm (10.2 m/s) Temperature: 180°F (82°C) Standard Construction Frame: 6063T5 extruded aluminum (0.063 in. [1.6mm] thickness) Blades: 6063T5 extruded aluminum. (0.050 in. [1.3mm] thickness) Axle Bearings: Synthetic polycarbonate

Motors and actuators should never be sprayed directly with water, steam or solvents. 3. Filter Maintenance (Model ESRMDF) Aluminum mesh filters should be cleaned on a regular basis for optimum fan efficiency. The frequency of cleaning depends upon the cleanliness of the incoming air. To remove filters in fan sizes 24-30, first remove the hood. This is accomplished by removing the two fasteners on one side of the hood and loosening the other two fasteners in the other side of the hood. Hinge the