There are several ways you can tell if your blower motor is going bad. One way to tell is by listening for strange noises coming from the motor. Another way to tell is by checking the voltage at the motor terminals. If you notice that the voltage is low, this could be an indication that the motor is going bad.
No Airflow
If you notice that there is no warm air at all coming through your heat registers, then you may have a broken blower motor. This generally means the blower motor has failed completely, which may indicate there have been problems for a while.
A Failed Motor
An HVAC blower motor will occasionally fail due to age, wearing out, or not being cleaned regularly. Symptoms may include strange noises, burning smells, or just plain refusing to turn on. If this happens and the motor is no longer operable, a new blower motor may be needed.
One of the most telling signs is if the blower motor isn't blowing air at all or the airflow is weaker than usual. If you set your AC or heater to the highest setting and barely feel a breeze, your blower motor control module could be the issue. Another symptom to watch for is the blower motor running inconsistently.
Blower Motor Resistor Test
Typically, if the fan will work on some speeds but not on others, the resistor is suspect. Okay, let's say there's no melting going on, but your fan doesn't work on all speeds. Typically, if the fan will work on some speeds but not on others, the resistor is suspect.
Installing a new heating and air conditioner blower motor could cost around $150 to $250, with most of that coming from labor costs. HVAC technicians usually go for around $75 to $125 per hour. A blower motor replacement might take anywhere from one-and-a-half to two-and-a-half hours.
Typically, the lifespan of furnace blower motors spans from a minimum of 10 years up to about 20 years, with most enduring an average period between 15 and 20 years.
Faulty Blower Motor
If your blower motor is experiencing some issues, you may hear a high-pitched squeal or whistling sound. You may also experience rattling and loud screeching noises. The motor blower pushes warm air out of the furnace through the ducts into your home.
On some platforms, a faulty blower motor relay will cause the blower not to work at all, which means there will be no airflow from the A/C. On others, the blower won't work on “high blow” but all the other speeds will work. The blower motor relay fails because it regularly deals with high current loads.
If the blower motor is going bad, it will struggle to operate the fan. The result will be weak airflow coming from the vents inside your living spaces. This airflow issue can be one of the main symptoms that indicate the component needs to be replaced.
A blower motor should last at least 10 years, and could last up to 20, depending on the type of HVAC unit you have in your home. There are a few warning signs that your blower motor is damaged, including little-to-no airflow coming from your vents, a burning smell, and skyrocketing energy bills.
Electrical Burning Odor
Electrical burning smells can be highly alarming. This odor could indicate an overheated blower motor. Blower motors commonly overheat due to clogged air filters.
Since the module regulates the entire AC system, inconsistent cooling, out-of-date software, and uneven air distribution are typical signs of a broken AC control module.
The most common symptom of a bad blower motor resistor is that you will only notice that your blower is working on the highest speed setting or that it won't work at all. The main symptoms of a bad blower motor resistor include: Only One Speed From Blower Motor. Various Airflow Settings Not Working.
If the sound is louder than typical and lasts longer than normal, it can be a sign of a problem with dirty burners, high gas pressure, or a malfunctioning heat exchanger, all of which could compromise the equipment's functionality and safety.
Some of the reasons a blower motor might fail are overheating, and excessive moisture. When dust, dirt, and debris build up, it can cause the windings and bearings to burn up more quickly.
Average Costs for Blower Motor Replacement
Standard Blower Motors: These might cost between $400-700, excluding labor. Advanced Multi-Speed or Variable-Speed Motors: These are generally more expensive, with costs ranging between $650-1250, not including labor.
The blower motor won't spin – If the rotor that holds the fan blower wheel won't spin or is difficult to turn, the blower motor is likely broken. If the engine is receiving appropriate power and the capacitor is functioning correctly, but the blower will not spin freely, it may have seized, which is not uncommon.
Your AC's blower motor is responsible for moving air through your air conditioner to cool it and then pushing it back out into your home. Without this incredible component, your AC can't provide any cooling effect, no matter how much the compressor runs.
The replacement of the blower motor is common and straightforward, so most shops will perform the repair — many on the same day.