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Dayton 21"H-W 4.5"L Aluminum Backdraft Damper: For 18 in Fan, Single Panel, 21 in H - Ceiling/Roof-Mount Backdraft Dampers
DaytonCeiling/Roof-Mount Backdraft Dampers

Dayton 21"H-W 4.5"L Aluminum Backdraft Damper: For 18 in Fan, Single Panel, 21 in H

The Dayton 4HX66 is a ceiling/roof-mount backdraft damper with a 21-inch height, 21-inch width, and 4.5-inch length, designed for use with an 18-inch fan. It features a single-panel flat blade design, felt seals, and…

SKU 3G-OTH-74740

Brand
Dayton
Item
21"H-W 4.5"L Aluminum Backdraft Damper: For 18 in Fan, Single Panel, 21 in H
Category
Ceiling/Roof-Mount Backdraft Dampers
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Technical Specifications

Dayton
Manufacturer Part Number
4HX66
Type
Single Panel, 21 in W, Felt
D
2 in
H
21 in
Blade Type
Flat Blade
Airflow Direction
Vertical
Mounting Position
Horizontal
Maximum Air Velocity
2000 fpm
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Dayton Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Dayton 4HX66 is a ceiling/roof-mount backdraft damper with a 21-inch height, 21-inch width, and 4.5-inch length, designed for use with an 18-inch fan. It features a single-panel flat blade design, felt seals, and a 2-inch depth, with vertical airflow direction and horizontal mounting position. The damper supports a maximum air velocity of 2000 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 4HX66 backdraft damper used for?

The Dayton 4HX66 backdraft damper prevents reverse airflow in ceiling or roof exhaust systems. It mounts horizontally with an 18-inch fan, using a single-panel flat blade and felt seals to close automatically when the fan stops, maintaining ventilation efficiency.

What are the specifications of the Dayton 4HX66 backdraft damper?

The Dayton 4HX66 has a 21-inch height, 21-inch width, 2-inch depth, and 4.5-inch length. It supports vertical airflow at a maximum velocity of 2000 fpm, with a flat blade design and felt seals. Mounting position is horizontal, for use with an 18-inch fan.

Where to buy the Dayton 4HX66 backdraft damper worldwide?

3G Electric supplies the Dayton 4HX66 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 single-panel, felt-sealed damper.

How to install the Dayton 4HX66 backdraft damper?

Mount the Dayton 4HX66 horizontally in the duct or roof curb, ensuring the blade pivots freely and the felt seals contact the frame evenly. Secure with fasteners rated for the duct material. Verify vertical airflow direction matches the fan discharge before final tightening.

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 ceiling/roof-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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