3 Common Causes Of Blower Motor Failure In Furnaces

The average furnace doesn't fail all at once. Instead, individual components can suffer premature failure well before the rest of the furnace is ready for retirement. For instance, the blower motor that handles airflow throughout the entire furnace can suddenly stop working, leaving your furnace without any way to circulate heat throughout your home.

The following highlights three ways your furnace's blower motor can suddenly give up the ghost, along with some advice on preventing premature blower motor failure.

1. Debris Buildup

Ventilation is crucial for any electric motor, but it's also an overlooked factor in a blower motor's premature demise. All electric motors generate heat and need some degree of ventilation to expel excess heat that would otherwise build up and eventually damage the motor. When dust, grime, and debris accumulate around the motor, the steady buildup slowly closes off the motor's ventilation, trapping heat within the motor and setting the stage for blower motor failure.

Think about all of the dust bunnies you've probably pulled out of your computer and how it ran cooler afterward. The same also applies to your blower motor and its relationship with dust and debris. Keeping your blower motor dust-free will also guarantee a significantly longer lifespan.

2. Poor Lubrication

Electric motors and other moving parts also need occasional lubrication. The lubricant creates a thin layer between the motor's bearings and outer surfaces, minimizing metal-on-metal contact as well as friction and heat. A lack of proper lubrication will quickly destroy the bearings, creating extreme friction that eventually leads to the blower motor's death.

The best way to safeguard against lubrication-related failures is with a bi-annual furnace inspection by a trusted HVAC specialist.

3. Age-Related Wear

In most cases, time is the biggest adversary against your furnace. While most blower motors are designed to last throughout the furnace's entire lifespan, they won't last forever. Cumulative wear and tear will take its toll on the motor, making sudden failure more likely as your furnace nears the end of its service life. Proper maintenance can help stretch your blower motor's lifespan, but it will wear out eventually.

A few common signs of age-related wear for furnace blower motors include rising electric bills due to the motor's increasing energy consumption and airflow that becomes progressively weaker as time goes on.

Most furnaces typically offer a 15 to 20-year service life before a complete replacement becomes necessary. If you're getting lackluster heat from your furnace, then it's worth checking your blower motor's age. Contact a heating repair company like Ricotta Heating & Air if you run into any issues.