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Dayton 39.75"H-W 4.5"L Aluminum Backdraft Dampr: For 40 in Fan, For 40 in Nominal Duct Dia - Universal-Mount Backdraft Dampers
DaytonUniversal-Mount Backdraft Dampers

Dayton 39.75"H-W 4.5"L Aluminum Backdraft Dampr: For 40 in Fan, For 40 in Nominal Duct Dia

The Dayton 3HHN2 is a universal-mount backdraft damper designed for use with a 40-inch fan and 40-inch nominal duct diameter. It features a single-panel, flat blade construction with aluminum material, supporting…

SKU 3G-OTH-74708

Brand
Dayton
Item
39.75"H-W 4.5"L Aluminum Backdraft Dampr: For 40 in Fan, For 40 in Nominal Duct Dia
Category
Universal-Mount Backdraft Dampers
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Technical Specifications

Dayton
Manufacturer Part Number
3HHN2
Type
For 40 in Nominal Duct Dia, Single Panel
Blade Type
Flat Blade
Airflow Direction
Vertical
Mounting Position
Horizontal
Maximum Air Velocity
2250 fpm
View Full Spec Sheet

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Dayton Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Dayton 3HHN2 is a universal-mount backdraft damper designed for use with a 40-inch fan and 40-inch nominal duct diameter. It features a single-panel, flat blade construction with aluminum material, supporting vertical airflow direction and horizontal mounting position. The damper has a maximum air velocity of 2250 fpm and measures 39.75 inches in height and width with a 4.5-inch length.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the Dayton 3HHN2 backdraft damper used for?

The Dayton 3HHN2 backdraft damper prevents reverse airflow in exhaust or ventilation systems using a 40-inch fan. It mounts horizontally, allows vertical airflow, and closes automatically when the fan stops, protecting equipment and maintaining system efficiency in industrial HVAC applications.

What are the specifications of the Dayton 3HHN2 backdraft damper?

The Dayton 3HHN2 is a single-panel, flat-blade aluminum damper for 40-inch nominal duct diameter. It measures 39.75 inches high and wide with a 4.5-inch length, supports vertical airflow, mounts horizontally, and handles a maximum air velocity of 2250 fpm.

Where to buy the Dayton 3HHN2 backdraft damper worldwide?

3G Electric supplies the Dayton 3HHN2 backdraft damper to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this universal-mount damper.

How to install a Dayton 3HHN2 backdraft damper?

Install the Dayton 3HHN2 damper in a horizontal duct section with the airflow arrow pointing upward. Ensure the damper frame seals against the duct flange and that blades swing freely. Secure with sheet metal screws and verify vertical airflow direction before system startup.

Used in

Common applications for Dayton
HVAC ventilation — DAYTON centrifugal upblast roof exhaust fans (SKU 7M7U3) for kitchen exhaust systems
Mechanical power transmission — DAYTON HTD timing pulleys (SKU 404GV0) for conveyor belt drives
Process water handling — DAYTON self-priming centrifugal pumps (SKU 2ZXT4) for dewatering or transfer
Roofing and building services — DAYTON fixed ventilated roof curbs (SKU 4HX59) for filtered supply fan installations
Material handling — DAYTON latch assemblies (SKU 2KEN4) for electric chain hoist hook safety
Industrial air movement — DAYTON downblast roof exhaust fans (SKU 3HFL9) for clean air exhaust in manufacturing plants

Dayton Products

3G Electric supplies Dayton universal-mount backdraft dampers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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