Finding the Correct Furnace Blower Assembly
Furnace blower assemblies are the parts of the system exposed to the most wear and tear due to the changes in airflow requirements, exposure to outside contaminants and several other factors. That means that HVAC service companies are regularly tasked with replacing parts like the blower wheels, motors and housings. However, there are many design differences that manufacturers incorporate in order to maintain performance standards.
Trying to keep track of all these differences can be difficult, but the below guide will outline some of the major differences that a manufacturer’s distributor will keep track of to ensure that the right assemblies and parts are available to service providers regardless of which model they are repairing.
Types of Motors
Motors are no longer simply “on-off” options that are matched to the voltage needed to run inside a building. Variable-speed fans and updated controls mean that manufacturers are continuing to look for the options that provide the right efficiency and performance statistics without increasing first cost to too great a degree.
It’s crucial for HVAC servicing companies to keep apprised of changes in manufacturers’ choices for furnace blower assembly motors because often times the housing and blower wheels may fit the system as a whole, but older drive systems will be unable to meet the performance specifications and lead to issues down the road.
Types of Housings
The housing used in a furnace blower assembly matters both in the manufacturing process and the design. In order to meet contaminant exclusion standards, an industrial blower assembly might need to be machined from a single piece of aluminum or steel to ensure rigidity and compliance. In other cases, stamped or welded enclosures will be more cost effective in less extreme environments.
Another reason to keep furnace blower assembly inventories up to date is changes in designs. Proper airflow is crucial for efficiency and manufacturers continue to update their designs to improve proper movement.
Types of Blower Wheels
The blower wheel also has a significant number of design considerations that play a role in terms of longevity, performance and efficiency numbers. Most are designed as centrifugal systems, meaning that the air exits at a 90 degree angle from where it enters.
However, there are many different ways of designing blower wheels depending on the airflow rate requirements, likeliness of debris and cost. The most common is the so-called “squirrel wheel” which is also known as a forward curved impeller. They are inexpensive and capable of continuing to operate during low airflow conditions, but the exposed blades can become damaged.
In industrial settings, the blades are usually coated or designed in a different fashion in order to protect them from corrosive air or contaminants. One common option is the backward inclined centrifugal blower wheel, which can operate at much higher speeds and works in higher-temperature settings. The individual blades can be curved, flat, or shaped like an airfoil.
Other designs include radial tip blowers that add design features that maintain high air flow regardless of air quality, and inline centrifugal blowers that may be rated for the most extreme conditions.
To summarize, while they may look very similar at first glance, centrifugal blower wheels have many small design differences that can significantly impact their ability to provide the performance in specified conditions.
Find the Furnace Blower Assembly You Need
As a leading distributor for the most trusted names in commercial HVAC, Affiliated Parts has the furnace blower assembly kits in order to maximize the performance and efficiency of your systems or those of your clients. As our trusted partners update their designs, we stock the right components and full kits to ensure that service providers can find the exact fit for their customers’ systems.
Shop our complete list of replacement parts for commercial HVAC systems or contact us for more information.