What does a blower motor do?

A blower motor is a crucial component in many heating, ventilation, and air conditioning (HVAC) systems. It plays a vital role in circulating air throughout a building, ensuring that the desired temperature and air quality are maintained. This article will provide a detailed explanation of the function and importance of a blower motor in HVAC systems.

What is a Blower Motor?

A blower motor is an electric motor that is responsible for powering the blower fan in an HVAC system. The blower fan is responsible for drawing in air from the return duct, passing it through the system's components (such as the furnace or air conditioner), and then pushing the conditioned air out through the supply ducts and into the living or working space. The blower motor provides the necessary force to move the air through the HVAC system.

How Does a Blower Motor Work?

The blower motor is typically located within the HVAC unit, often near the furnace or air handler. When the HVAC system is turned on, the blower motor receives an electrical signal, causing it to spin the blower fan. As the fan rotates, it creates a suction that pulls air from the return duct into the HVAC system. The air is then pushed through the system's components, such as the heat exchanger or cooling coils, where it is heated or cooled as needed. Finally, the conditioned air is expelled through the supply ducts and into the living or working space.

Importance of the Blower Motor

The blower motor is a critical component of an HVAC system, as it is responsible for the following:

• Air Circulation: The blower motor ensures that air is continuously circulated throughout the building, helping to maintain a comfortable and consistent temperature.


• Air Quality: By moving air through the HVAC system, the blower motor helps to filter out dust, pollen, and other airborne particles, improving the overall air quality.


• Efficiency: A properly functioning blower motor helps to ensure that the HVAC system operates efficiently, reducing energy consumption and costs.

Without a properly functioning blower motor, an HVAC system would be unable to effectively circulate and condition the air, leading to poor temperature control, reduced air quality, and decreased energy efficiency.

Conclusion

The blower motor is a vital component of an HVAC system, responsible for circulating air throughout a building and ensuring that the desired temperature and air quality are maintained. By understanding the role and importance of the blower motor, homeowners and building managers can better maintain and troubleshoot their HVAC systems, ensuring optimal performance and energy efficiency.

What does a blower motor do on a car?

A car's blower motor is an electric fan that pushes air through the heating, ventilation, and air conditioning (HVAC) system to control the cabin's temperature. It circulates heated air from the heater core or cooled air from the evaporator, sending it out through the vents for your comfort. The motor's speed can be adjusted by the fan speed setting on your climate control, and a failure can result in no or low airflow from the vents.
 
This video explains the function of a blower motor and why it might fail: 42sglobalpartsdistYouTube · Jun 15, 2020
How it works

• The blower motor draws power from the car's battery and turns a fan, which pulls in air from outside or recirculates air from inside the cabin. 
• This air is then pushed through the appropriate component to change its temperature: 
  • For heating: The air passes over the hot heater core. 
  • For cooling: The air passes over the cold evaporator. 
• The climate control system then directs this conditioned air through the ducts and out of the vents. 
• The speed of the blower motor is controlled by relays, switches, and a blower motor resistor (or module in newer cars) to provide different fan speeds. 

Common issues

• No airflow: A complete lack of air from the vents when the AC or heat is on is a common symptom of a failing blower motor or a blown fuse. 
• Unusual noises: Rattling, grinding, or squealing sounds can indicate a bad blower motor, often caused by a worn-out bearing or debris caught in the fan cage. 
• Only works on high: If the fan only works on the highest setting, it is usually a symptom of a faulty blower motor resistor, not the motor itself. 

This video shows the symptoms of a bad blower motor: 53sEasyAutoFixYouTube · Jul 9, 2022

Can a car run without a blower motor?

Yes, you can drive without a blower motor, but it will make driving uncomfortable and can affect your defroster's ability to clear the windshield. The blower motor is not critical for engine operation, but without it, you will not have air conditioning or heating, and your defroster will work very slowly, which can be a safety hazard in bad weather. 
What happens without a blower motor

• No climate control: You will not have air conditioning in the summer or heat in the winter, making the cabin temperature unpleasant. 
• Defroster issues: The defroster will not work properly, making it difficult or impossible to clear condensation, fog, or ice from your windshield. 
• Engine overheating (unlikely for the interior blower): Some sources suggest a possible link to engine overheating if the engine's cooling fans are being confused with the interior blower, but the internal blower motor is generally not tied to the engine's core cooling system. The separate engine cooling fans are different from the interior cabin blower. 
• Discomfort: Driving will be uncomfortable, especially in extreme temperatures. 

Why it's not recommended

• Safety hazard: The inability to properly defrost and defog your windshield creates a significant safety risk, especially in poor weather conditions. 
• Discomfort: It's miserable to drive without the ability to control the temperature inside the car. 
• Component failure risk: While you can technically drive, it is recommended to fix it as soon as possible to avoid further issues and maintain safe driving conditions. 

What to do

• Drive cautiously: Be extra careful when driving in hot, cold, or humid weather due to the lack of defrost and A/C. 
• Seek a replacement: Get the blower motor replaced as soon as you can. It is a relatively common part to replace, and driving without it is a poor long-term solution. 

What happens when your blower motor goes out?

When a blower motor fails, your HVAC system will experience a lack of airflow or reduced airflow from the vents, and your defroster may not work effectively. Other symptoms can include unusual noises like grinding or whining, the system only working on the high setting, or a burning smell. If ignored, a failing motor could potentially overheat or cause the system to become less efficient.
 
This video explains the symptoms of a bad blower motor: 49sEasyAutoFixYouTube · Jul 9, 2022
Key symptoms

• No or weak airflow: The most common sign is little to no air coming from your vents when the AC or heater is turned on. 
• Poor defroster performance: A failing motor can make it difficult or impossible to defrost your windshield, which is a safety hazard. 
• Strange noises: You may hear new sounds such as grinding, whining, or squealing coming from the unit. 
• Only one fan speed works: If you can only get air on the highest setting, a failing blower motor resistor is often the cause. 
• Burning smell: A burning smell coming from the vents is a serious sign that the motor is overheating and could be a fire hazard. 
• Overheating or tripping breakers: A struggling or failing motor can draw too much current, potentially causing it to overheat or trip your circuit breaker. 

What to do

• Check fuses: Before assuming the motor is bad, check if the fuse is blown, as this is a common and easy fix, say Palumbos Automotive. 
• Do not ignore burning smells: If you smell a burning odor, turn the system off immediately to prevent damage or a fire hazard and call a professional. 
• Contact a professional: Since the symptoms can be similar to other problems and a failing blower motor can cause further damage, it is best to have a qualified technician diagnose and repair the issue. 

Does a blower motor affect AC in a car?

The blower motor is responsible for circulating the air through the AC system. If the blower motor is not working, the air will not be circulated properly, which will cause warm air to be blown into your car.