No, a furnace blower is not suitable for a central dust collection system. While it may seem like a cost-effective solution, these fans (technically known as forward curve or “squirrel cage” fans) are designed for HVAC, not material handling.
Why Furnace Blowers Fail for Dust Collection
There are three critical technical reasons why these fans cannot perform this task:
Insufficient Static Pressure: A central dust collection system typically generates 8″ to 10″ of static pressure (resistance) that the fan must overcome. Furnace blowers are “light duty” and only capable of approximately 1.5″ static pressure. They simply do not have the strength to pull air through the ductwork and filters.
Inadequate Air Velocity: To keep heavy wood chips and dust suspended in the air stream, you need a transport velocity of roughly 4,000 FPM (feet per minute). HVAC systems are designed to move clean air slowly at only 1,000 FPM. At this low speed, dust will drop out of the air stream and clog your pipes.
Wrong Blade Design: Squirrel cage fans have curved, lightweight blades that trap debris. They are not designed for impact.
The Correct Solution: Radial Blade Centrifugal Fans
The type of fan required for dust collection is a radial blade centrifugal fan. Unlike furnace blowers, these are designed for high-performance material handling:
Self-Cleaning Blades: They feature straight blades that prevent material buildup.
High Pressure: They are engineered to operate at high speeds, generating the required 12″+ water gauge pressure.
Heavy-Duty Construction: The housings are typically welded and heavy-duty to withstand the impact of wood chips and debris.