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Broan 4 in. Duct Collar with Backdraft Damper for Models 636/636AL
Regular price $18.30Orders start at $399 — combine any items to reach the minimum. Learn more
Broan 4 in. Duct Collar with Backdraft Damper for Models 636/636AL
This Broan 4 in. duct collar with backdraft damper is a replacement part for Broan models 636 and 636AL residential exhaust ventilation units. Sold as a single piece, it connects 4 in. ductwork to the fan while the built-in damper helps stop backdrafts when the fan is off.
Key Features:
- Backdraft damper: Built-in damper helps prevent outside air from flowing back through the duct when the fan is off.
- 4 in. duct size: Fits standard 4 in. duct connections.
- Model-specific fit: Designed for Broan models 636 and 636AL.
- Genuine replacement: Broan-NuTone residential exhaust ventilation and air quality part.
- Easy swap: Direct replacement collar for service and repair work.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Broan |
| Sell unit | 1 piece |
| Product line | Duct Collar Backdraft Damper |
| Available sizes | 4 in. |
| Dimensions | 4 in. |
| Compatible models | Broan 636 / 636AL |
| Type | Duct collar with backdraft damper |
| Intended use | Residential exhaust ventilation duct connection |
| Pack quantity | 1 |
Fit and Compatibility:
Made for Broan models 636 and 636AL exhaust ventilation units with 4 in. duct connections; not listed for other fan models.
Frequently Asked Questions (FAQ):
Q: What is included?
A: One Broan 4 in. duct collar with backdraft damper.
Q: Which fans does it fit?
A: It is specified for Broan models 636 and 636AL.
Q: What duct size does it accept?
A: It is sized for 4 in. duct.
Q: What does the damper do?
A: The backdraft damper helps keep outside air from entering through the duct when the fan is not running.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
When servicing a 636 or 636AL exhaust fan, replacing a worn or missing duct collar is a quick way to restore proper airflow control and stop backdrafts. Verify the 4 in. duct match before ordering, and make sure the damper swings freely after installation so it can seat closed. Keep the connection sealed where the collar meets the duct.
Disconnect power to the ventilation unit before installing or servicing the duct collar.
Get the Broan 4 in. duct collar with backdraft damper to restore your 636/636AL ventilation unit.
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