Blower Motor Not Working? Signs, Causes, and Troubleshooting

Behind the scenes, a range of components are working together to condition the air in your home. One of the most important heating, ventilation, and air conditioning (HVAC) parts is your blower motor. If this essential element fails, you’ll quickly notice poor airflow, overheating, and higher electricity costs. 

While there are some basic checks you can do on your own, you should never attempt electrical or motor repairs yourself. If the blower motor is genuinely the issue, Rogue Valley Heating, Cooling, & Electrical’s technicians can help you diagnose and repair the problem.

What Does a Blower Motor Do in Your HVAC System?

In your HVAC system, the blower motor is responsible for pulling in unconditioned air. This conditioned air is pushed across the evaporator coil for heat pumps and air conditioners. On your furnace, it is pushed across the heat exchanger. Afterward, the conditioned air is circulated to regulate the temperature.

How the Blower Motor Moves Heated and Cooled Air

The blower motor has a fan that looks like a squirrel cage. When the squirrel-cage fan turns, it pulls in indoor air that is then delivered to the heat exchanger or evaporator coil. This entire process begins when the thermostat signals your blower motor to start turning.

Why Blower Motor Problems Affect Comfort and Efficiency

If the blower motor isn’t working right, your HVAC system won’t produce enough air. This causes it to work harder to reach the same temperature. Besides leading to premature repairs and breakdowns, this increased workload can increase your energy bills. Because the unit is struggling to reach the right temperature, your family’s comfort will also be affected.

Signs Your Blower Motor May Not Be Working

There are a few common indications that your blower motor may not be working properly.

Weak Airflow From Vents

If your blower motor is struggling to push air out, one of the first signs will be weak airflow.

No Air Coming Out Even When the System Is On

Once the blower motor breaks down completely, your HVAC system may completely stop blowing air.

Strange Noises Like Humming, Screeching, or Rattling

Any unusual noises, like screeching, rattling, and humming, may indicate a problem with your blower motor. Odd sounds can also be caused by other problems, so you should always get them investigated by a professional HVAC technician.

Burning Smells or Overheating

If you have a blocked air filter or a blocked vent, it can cause your blower motor to work harder than necessary. In turn, this can cause it to overheat and produce a burning smell.

System Shutting Down Unexpectedly

Whenever the blower motor overheats, it triggers your HVAC system to shut off as a safety mechanism.

Common Causes of a Blower Motor Not Working

There are a few common reasons why your blower motor may stop working. 

Tripped Breaker or Power Issue

Blown fuses, tripped breakers, and faulty wiring can prevent the blower motor from receiving the energy it needs to operate.

Dirty Air Filter Restricting Airflow

When a filter is clogged, it stops airflow from reaching the blower motor. In turn, this makes the motor work harder to reach the right temperature. You’ll notice comfort and efficiency changes right away. If the problem isn’t addressed, it will eventually cause the component to break down completely.

Faulty Capacitor

The capacitor stores energy. When the HVAC system switches on, this stored energy is used to start it. A faulty capacitor won’t switch on your HVAC system. The best way to fix this problem is by having a professional HVAC technician replace the faulty capacitor.

Blower Belt Issues on Older Systems

On older systems, the blower motor belt can slip or become cracked. When this happens, you’ll notice reduced airflow, a high-pitched noise, and burning odors.

Worn Motor Bearings or Failed Motor

A grinding or squealing sound typically means that your unit has bad bearings. While lubricating the bearings may provide a temporary fix, they may need to be replaced. Similarly, a motor’s resistor or relay can fail and cause the motor to stop working.

Control Board or Thermostat Problems

If the HVAC system’s control board or thermostat fails, the system may not be able to sense the temperature appropriately and trigger the blower motor to turn on.

Safe Troubleshooting Steps Homeowners Can Try

While many HVAC problems should be left to the professionals, there are a few simple steps you can take on your own.

Check Thermostat Settings

First, make sure your thermostat is set to the right mode and temperature. To see if the thermostat is working, try changing the temperature. If it’s working, your system should kick on right away.

Replace a Clogged Air Filter

Air filters should ideally be replaced every 30 to 90 days as part of your routine HVAC maintenance.

Inspect the Circuit Breaker

Sometimes, a breaker will trip and stop your blower motor from switching on. If this is the issue, you can reset the breaker. However, if it trips again right away, there is an underlying problem that should be diagnosed by a professional.

Make Sure Vents and Returns Are Open and Unobstructed

To ensure proper airflow, make sure all of the returns and vents are open and not blocked.

Listen for Motor Sounds That Help Narrow Down the Issue

Pay attention to any sounds, smells, or symptoms that can help you determine what the problem is.

Troubleshooting Steps a Professional Will Perform

When you reach out for heating and cooling repairs, our HVAC technicians will perform the following steps to determine the problem.

Testing Voltage and Capacitor Performance

First, we’ll check the voltage to see if the capacitor is working properly.

Checking Blower Wheel and Motor Amp Draw

We will inspect the blower wheel and amp draw for malfunctions.

Inspecting Control Board and Relay Signals

To make sure your HVAC system is being properly signaled to start, we’ll inspect your control board and relay signals.

Confirming Whether Repair or Replacement Makes More Sense

Once we know what the problem is, we’ll work with you to determine whether a repair or replacement makes more sense for your financial goals, efficiency needs, and personal comfort.

When a Blower Motor Can Be Repaired vs. Replaced

Our team will help you decide if a blower motor repair or replacement makes more sense for your needs.

Situations Where a Capacitor or Wiring Fix May Solve the Problem

If the capacitor or wiring is at fault, we’ll fix those issues instead of replacing the blower motor. 

Signs the Blower Motor Itself Has Failed

When the blower motor itself has failed, it’s generally better to replace the component completely. 

Depending on the circumstance, it may be necessary to replace the entire unit. If your HVAC system is already older than 10 years, requires frequent repairs, or uses outdated refrigerant, it may be time to replace the entire unit.

When To Call for HVAC Repair

If you notice repeated breaker trips or burning odors, call for help right away. Both of these issues are immediate safety concerns. 

We also recommend calling for help if there is no airflow during extreme weather. When temperatures become uncomfortable, you can’t afford to be left without a functioning HVAC system.

How To Prevent Future Blower Motor Problems

To avoid future problems, remember the following tips and best practices. 

Change Filters Regularly

Depending on the manufacturer’s specifications, your air filter should be changed every 30 to 90 days. During periods of intense use, they should be replaced more often.

Schedule Seasonal Maintenance

For the best comfort and efficiency, we recommend scheduling a spring and fall HVAC tune-up each year.

Keep the System Clean and Airflow Balanced

By maintaining your system, you can avoid unexpected breakdowns. Clean around the outdoor condenser coils, remove obstructions that are blocking your vents, and clear away any debris from around your outdoor unit.

FAQs

Can a furnace run if the blower motor is bad?

It cannot run safely. Without a functioning blower motor, the furnace will overheat and shut down. 

Is a bad capacitor the same as a bad blower motor?

No, they are different components within the same system. You often hear them talked about at the same time because the capacitor is responsible for triggering the blower motor to start.

How much does blower motor repair usually cost?

It depends on the repair involved. A full replacement often costs around $300 to $900. Repairs can cost between $150 and $1,500.