Dayton
Dayton 4HX73 Backdraft Damper 12.75 in Square 4.5 in Deep
Aluminium backdraft damper for square ducts, 12.75 in frame with 4.5 in depth and 0.4 sq ft free area
- TypeWall Mount, Supply
- Aluminium construction resists corrosion
- Square 12.75 in frame fits standard openings
- 5 in depth allows compact wall mounting
- Single panel operates up to 2250 fpm airflow
- 4 sq ft free area minimises pressure drop
Square 12.75 in Backdraft Damper
The Dayton 4HX73 is an aluminum backdraft damper designed for wall-mount supply applications. Its square frame measures 12.75 inches by 12.75 inches with a 4.5 inch depth. The single-panel construction provides a 0.4 sq ft free area and handles air velocities up to 2250 fpm. It fits a 10 in fan diameter.
Verify Duct Shape and Fan Size
Confirm your ductwork is square and matches the 12.75 in rough opening dimensions before ordering. The damper is built for a nominal 10 in fan diameter and a frame depth of 1 5/8 in. Ensure the mounting surface accommodates the aluminum frame thickness of 0.1 in. No electrical wiring or specific control voltage is required for this gravity-operated unit.
Replaces Worn Gravity Dampers
This unit replaces damaged or seized aluminum backdraft dampers in square supply ducts. The upgrade is worth it when existing louvers fail to seal, allowing unwanted air infiltration or backflow. It restores proper one-way airflow control without the need for motorized actuators. The 2250 fpm rating supports standard residential and light commercial supply velocities.
Highlights
- Aluminium construction resists corrosion
- Square 12.75 in frame fits standard openings
- 5 in depth allows compact wall mounting
- Single panel operates up to 2250 fpm airflow
- 4 sq ft free area minimises pressure drop
Specifications
| Brand | DAYTON |
|---|---|
| Type | Wall Mount, Supply |
Questions about this item
Does the Dayton 4HX73 backdraft damper come with mounting hardware or do I need to buy screws separately?
The damper is supplied as the aluminum frame and single panel only; mounting fasteners are not included and must be sourced separately.
How do I know if the 12.75 in square size with .4 sq ft free area matches my 10 in fan?
The unit is designed to fit a 10 in fan diameter, and the .4 sq ft free area aligns with that nominal size for proper airflow.
What does the 2250 fpm maximum air velocity mean for everyday ventilation use?
It indicates the damper blades will stay closed against backflow up to that speed, so typical residential supply fans operating well below 2250 fpm will not force the damper open unintentionally.
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