What Type of Blower Wheel do I Need?
TechXpert verified by Ken Kontra
The blower wheel design specified by the manufacturer should always be used during replacement. When choosing, you’ll want to select the one that delivers better energy efficiency, sufficient air velocity, and a stable rate of airflow and circulation.
A Selection that will Blow You Away
Centrifugal blowers are the main types available, and while each design operates a bit differently, the goal is the same: sustain a stable and satisfactory airflow.
Centrifugal blowers use high-speed impellers to produce highly accelerated airflow. The air changes direction twice: once when it enters the fan and once while leaving it.
These blowers are relatively quiet, and they can operate in different environments and serve a variety of purposes.
Positive Displacement Blowers
Positive displacement blowers are normally powered by direct-coupled electric motors and contain counter-rotating lobed rotors that move volumes of air through the blower. These blowers use mechanical force to increase the pressure of airflow and velocity. If your system requires higher pressures of airflow, a positive displacement blower is likely your best choice.
Variable-Speed Blower Motor
Variable-speed blowers work like your car on cruise control: they adjust to maintain a steady speed of airflow, even against resistance. If you haven’t cleaned your air filters in a while, this type of blower will still ramp up to deliver sufficient airflow in your system. Between heating or cooling run cycles, this blower may be set to operate at a low speed, energy efficient setting, that can constantly clean and humidify your air depending on whether you have an air cleaner or humidifier. When the system needs to heat or cool again, the blower will ramp up speed to deliver the required airflow.
Multi-Speed Blower Motor
Similar to variable-speed blowers, multi-speed blowers also adjust airflow – but with less precision. This type of blower works more like a ceiling fan with low, medium, and high settings. Multi-speed blowers can have up to five preset speeds that you can change based on your equipment airflow needs.
Finding the Right Blower Wheel
If you’re not sure what type of blower wheel your HVAC system needs, you can contact an HVAC professional to ensure you’re selecting the right one. It’s important to select a blower wheel that matches the applications of your HVAC system like ventilation and clean air filtration, rather than choosing one that is designed for other settings. Overall, a correct blower wheel will maximize the efficiency of your blower motor and the other parts of your HVAC unit.
Let's Get It Fixed!
Our virtual experts can diagnose your issue (for free!) and resolve simple problems.