Backdraft Dampers Backdraft Damper Training Application Backdraft dampers

Backdraft Dampers

Backdraft Damper Training Application Backdraft dampers allow air to flow in one direction only and prevent unwanted (hot/cold outside air, wind, etc. ) from “back-drafting” into the building. They only install in ducts, at walls, or in roofs and open automatically when air flows in the intended direction and automatically close when there is no air pressure or when airflow is in the opposite direction. Basic Functions • Intake/Exhaust • Barometric/Pressure Relief

Backdraft Damper Training Intake backdraft dampers allow supply airflow into a building while preventing conditioned air from escaping when the fan is off. Typical Applications • Intake Air Duct - Wall or plenum mounted • Intake side of rooftop evaporative cooler (requires counterbalance)

Backdraft Damper Training Exhaust backdraft dampers allow air to automatically exit the building and prevent outside air from entering the building. Typical Applications • In tandem with wall mounted exhaust fan. • Exhaust air duct - wall or plenum mounted • Roof top power ventilator • Rooftop gravity ventilator Backdraft Damper Roof Top Power Ventilator Wall Mounted Exhaust Fan

Backdraft Damper Training Barometric relief dampers open automatically under low velocity conditions - including natural airflow - and close automatically to prevent reverse airflow. Backdraft Damper Typical Applications • Rooftop gravity ventilator • Wall mounted relief (no duct or fan) Roof Top Gravity Ventilator

Backdraft Damper Training Pressure Relief Pressure relief dampers use counterbalance weights to maintain a relatively constant upstream pressure, they open automatically at higher pressures and close automatically when pressures drop. Typical Applications • Duct or plenum relief • Room relief

Backdraft Damper Training AMCA 500 D Test Requirements Test Samples • Pressure drop: 12 x 12, 12 x 48, 48 x 12, 24 x 24, 36 x 36 Pressure Drop • Ducted Inlet and Outlet - AMCA 5. 3 Lowest Pressure Drop • Ducted Inlet Only - AMCA 5. 2 • Plenum Mount - AMCA 5. 5 (Highest Pressure Drop) AMCA 5. 3 – Ducted Inlet & Outlet AMCA 5. 2 Ducted Inlet AMCA 5. 5 – Plenum Mount

Backdraft Damper Training Design Basics and Typical Application Light Duty • Most common type and widely used for intake, exhaust, barometric, and pressure relief applications where air pressures and velocities are low (≤ 2 in wg. & 1250 fpm). Medium Duty • Typically used for intake, exhaust, and pressure relief when pressure or velocity exceeds the light duty range (>2 in wg. & 1250 fpm, but ≤ 3 in. wg. And 2500 fpm. Industrial • Employed when the temperature, pressure, or velocity exceed standard commercial damper limits. Units are typically flange mounted directly to the duct or fan housing.

Backdraft Damper Training Light Duty Backdraft Dampers Applications – BD-50 • Gravity Intake and Exhaust • Prop-Fan Exhaust • Roof Top Power Ventilator – BD-51 • Intake or Exhaust – where damper blade noise is a concern – BD-52 • Evaporative Cooler – Discharge Side (down-flow only) – BD-54 • Pressure Relief Adjustable Counterbalance Weight Mounting Arrangements – Vertical Mount – Horizontal Mount • Up-flow • Down-flow (BD-52 Only) Caution – Multiple Sections – Maximum Velocity & Channel Frame Pressure Limits – No Exact Pressure Settings Vertical Mount Horizontal Mount Tie-Bar Integral Counterbalance Weight

Backdraft Damper Training Medium Duty Backdraft Dampers Applications Concealed Linkage – BD-60 • Fan Exhaust - Duct or Plenum Mount – BD-64 • Pressure Relief - Higher velocity Adjustable Counterbalance Weight Mounting Arrangements – Vertical Mount – Horizontal Mount • Up-flow only Caution Vertical Mount – Low-end velocity and pressure limits – No Exact Pressure Settings – Retarding Counterbalance Design Only - No assist to Open Hat-Channel Frame Horizontal Mount

Backdraft Damper Training Industrial Backdraft Dampers Applications – BD-84 Channel Frame Concealed Linkage • Fan Exhaust - duct or plenum mount Mounting Arrangements – Vertical Mount only Caution – Low-end velocity and pressure limits – No Exact Pressure Settings – Assist to Open Counterbalance design only Adjustable Counterbalance Weight

Backdraft Damper Training Options & Accessories Flange Frame • For flush mounting to equipment/wall • Intake or discharge Sleeve 304 Stainless Steel Construction Electric Actuator (BD-58 Only)

Backdraft Damper Training THANK YOU!