HVAC blower motors help keep you comfortable year-round by moving conditioned air from your furnace, air conditioner or heat pump throughout your home. It is a small electric motor housed in your furnace that powers your system’s blower fan (also in the furnace). Once the system heats or cools the air, the blower motor forces it through the duct system and out through the vents in rooms throughout the house.

Many systems include controls for your blower fan on your thermostat, which are shown as a fan icon or the word “fan.” The settings on your thermostat allow you to set your blower fan to run automatically or continuously. As the HVAC system heats or cools the air, the blower motor and fan force the conditioned air into your home’s ductwork, which delivers the air into individual rooms.

A properly functioning blower motor is crucial for maintaining comfortable indoor temperatures by effectively circulating heated or cooled air throughout your home, ensuring consistent airflow through vents, and contributing to overall system efficiency and air quality by filtering particles as the air passes through the system. It’s the driving force behind your home’s heating and cooling system, impacting comfort and energy usage.

Types of HVAC Blower Motors

Understanding the different types of blower motors can help you choose the right one for your needs, whether installing a new system or upgrading an existing one. Each type offers unique efficiency, cost and performance benefits.

• Single-speed blower motors operate at a fixed speed and turn off when the desired temperature is reached. They are most found in older HVAC systems.
  • Generally, the least expensive.
  • Run at a single, constant speed. They turn on and off based on the thermostat's demands, leading to more wear and tear and higher energy consumption.
  • Less efficient compared to other types.
    
    
• Multi-speed blower motors can operate at multiple preset speeds. They offer better control over airflow and maintain a more consistent temperature and humidity level while reducing energy use and noise.
  • Moderately priced.
  • Can switch between low, medium and high speeds.
  • More efficient, as it can adjust speed based on demand.

• Variable-speed blower motors provide the highest level of control and efficiency. They can adjust their speed continuously to match the home's heating or cooling needs.
• Highest initial cost.
• Adjusts speed dynamically for optimal performance.
• Most efficient, leading to energy savings.

When choosing the right HVAC blower motor, consider the factors mentioned above: budget, energy efficiency and comfort level. An HVAC professional can help you consider the size of your home and ductwork to select a motor that can deliver adequate airflow.

Signs of a Faulty Blower Motor
HVAC blower motors typically last about 10-20 years but can break down prematurely due to a lack of maintenance, wear and tear from dirt buildup, electrical issues or overuse. Some common signs of a failing blower motor include:

• Reduced Airflow: Less air coming out of the vents due to the motor struggling to push air through the system.
• Unusual Noises: Sounds like screeching or squealing could mean the blower has bad bearings. Hearing a rattle or banging sound could mean something is broken inside the motor.
• High Energy Bills: A failing blower motor may experience additional electrical resistance, which will cause it to consume more energy to make it run.
• Burning Smell: When your blower motor is struggling, it may start overheating, which is when you may experience a hot or burning smell coming from your vents.
• Tripped Circuit Breaker: A bad blower motor could cause the circuit breaker to trip repeatedly if it’s drawing too much power, but it could also be an issue with the condensing unit fan or the compressor. Do not ignore the problem and call to have a technician troubleshoot.

You should consider replacing or repairing your HVAC blower motor when these signs occur, but a professional HVAC technician can diagnose the issue and advise on the best course of action, whether it’s a repair or full replacement.

Maintenance

Recognizing the importance and longevity of your blower motor is crucial for maintaining a comfortable and energy-efficient living environment. By performing regular maintenance, addressing repairs swiftly and making informed decisions about part replacements, you can significantly extend the life of your blower motor and improve the overall efficiency of your HVAC system.

To prolong the lifespan of your HVAC blower motor, the most important regular maintenance practice is to clean and replace air filters frequently as a clogged filter restricts airflow, forcing the motor to work harder and causing premature wear and tear. Here are some steps to take to keep your blower motor in excellent condition:

• Replace air filters frequently
• Remove dust and debris around the motor with compressed air
• Ensure proper lubrication of moving parts (usually done by a technician during a tune-up)
• Schedule regular maintenance checkups with a professional

If your blower motor isn’t working or you are ready to upgrade it for better energy efficiency, call your local Lennox Dealer to schedule service or receive an estimate for new blower motor installation.

This has been reviewed by Lee Butler, Senior Product Marketing Manager, for accuracy. Lee brings 12 years of expertise in the HVAC space.