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Dayton 33.75"H-W 4.5"L Aluminum Backdraft Dampr: For 34 in Fan, For 34 in Nominal Duct Dia - Universal-Mount Backdraft Dampers
DaytonUniversal-Mount Backdraft Dampers

Dayton 33.75"H-W 4.5"L Aluminum Backdraft Dampr: For 34 in Fan, For 34 in Nominal Duct Dia

The Dayton 33.75"H-W 4.5"L Aluminum Backdraft Damper (SKU 3HHL9) is a universal-mount backdraft damper designed for a 34-inch fan and 34-inch nominal duct diameter. It features a flat blade type, supports vertical…

SKU 3G-OTH-74643

Brand
Dayton
Item
33.75"H-W 4.5"L Aluminum Backdraft Dampr: For 34 in Fan, For 34 in Nominal Duct Dia
Category
Universal-Mount Backdraft Dampers
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Technical Specifications

Dayton
Manufacturer Part Number
3HHL9
Type
For 34 in Nominal Duct Dia, Single Panel
Blade Type
Flat Blade
Airflow Direction
Vertical
Mounting Position
Vertical
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 33.75"H-W 4.5"L Aluminum Backdraft Damper (SKU 3HHL9) is a universal-mount backdraft damper designed for a 34-inch fan and 34-inch nominal duct diameter. It features a flat blade type, supports vertical airflow direction, and is intended for vertical mounting positions. The damper has a maximum air velocity of 2250 fpm.

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 3HHL9 backdraft damper used for?

The Dayton 3HHL9 backdraft damper prevents reverse airflow in vertical exhaust or intake ducts. It is designed for a 34-inch fan and 34-inch nominal duct diameter, with a flat blade that opens under forward airflow and closes when flow stops, protecting equipment and maintaining system efficiency.

What are the specifications of the Dayton 3HHL9 backdraft damper?

The Dayton 3HHL9 is a single-panel aluminum backdraft damper with a flat blade. It measures 33.75 inches high by 4.5 inches long, fits 34-inch nominal duct diameter, supports vertical airflow direction, mounts vertically, and handles a maximum air velocity of 2250 fpm.

Where to buy the Dayton 3HHL9 backdraft damper worldwide?

3G Electric supplies the Dayton 3HHL9 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 a quote and lead time on this and other Dayton ventilation products.

How to install a Dayton backdraft damper for a 34-inch fan?

Mount the Dayton 3HHL9 damper vertically in the duct, ensuring the airflow arrow points in the intended direction. Secure it with appropriate fasteners and seal the flange to prevent leakage. Verify the damper blade swings freely before system startup. Follow local codes and the fan manufacturer's guidelines.

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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