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Dayton 21"H 21"W Drnbl Extrd Alu Combo Dmpr: Flanged, 17 1/2 in H, 17 1/2 in W - Combination Dampers & Louvers with Drainable Blades
DaytonCombination Dampers & Louvers with Drainable Blades

Dayton 21"H 21"W Drnbl Extrd Alu Combo Dmpr: Flanged, 17 1/2 in H, 17 1/2 in W

The Dayton 20UA21 is a 21-inch by 21-inch combination damper and louver with drainable extruded aluminum blades and a flanged frame. It features a 45-degree blade angle and a maximum air velocity of 3,000 fpm. This…

SKU 3G-OTH-75228

Brand
Dayton
Item
21"H 21"W Drnbl Extrd Alu Combo Dmpr: Flanged, 17 1/2 in H, 17 1/2 in W
Category
Combination Dampers & Louvers with Drainable Blades
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Technical Specifications

Dayton
Manufacturer Part Number
20UA21
Type
17 1/2 in W, Aluminum
H
17 1/2 in
Blade Angle
45°
Maximum Air Velocity
3,000 fpm
View Full Spec Sheet

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

Product Description

The Dayton 20UA21 is a 21-inch by 21-inch combination damper and louver with drainable extruded aluminum blades and a flanged frame. It features a 45-degree blade angle and a maximum air velocity of 3,000 fpm. This unit is designed for applications requiring both airflow control and weather protection.

Frequently Asked Questions

What is the Dayton 20UA21 combination damper and louver used for?

The Dayton 20UA21 is used in HVAC and industrial ventilation systems where both airflow control and weather protection are needed. Its drainable extruded aluminum blades and flanged frame make it suitable for outdoor air intakes and exhaust applications that require resistance to rain and debris.

What are the specifications of the Dayton 20UA21?

The Dayton 20UA21 has a 17 1/2 in by 17 1/2 in duct size, a 21 in by 21 in overall flange, extruded aluminum drainable blades with a 45° blade angle, and a maximum air velocity of 3,000 fpm. The brand is Dayton and the manufacturer part number is 20UA21.

Where to buy the Dayton 20UA21 worldwide?

3G Electric supplies the Dayton 20UA21 combination damper and louver to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for availability and a quote for your region.

How to install the Dayton 20UA21 combination damper?

Install the Dayton 20UA21 with the flanged frame securely fastened to the duct or wall opening, ensuring the blades open in the direction of airflow. Follow standard HVAC damper installation practices: verify clearance for blade rotation, seal the flange perimeter, and test operation before commissioning.

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 combination dampers & louvers with drainable blades. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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