Why Is My Furnace Making Noise?
If your furnace emits odd sounds, it is asking you to pay attention.
When you hear a noise, such as a clank, rattle, or squeal from your heating, ventilation, and air conditioning (HVAC) system, think of it as a distress signal. Something is amiss, and you need to find out what it is before it compromises your comfort.
Midwest Air Pros can recommend an HVAC professional to help diagnose the sounds and offer a solution. We work with teams of expert technicians in Iowa, Kansas, Missouri, and Nebraska who repair, replace, install, and maintain heating and cooling systems.
Normal Furnace Sounds
Your furnace has numerous parts that must work together to heat air and move it through a maze of ductwork into each room in your Des Moines home. You can hear the whoosh of the ignition lighting the burners when the heating cycle starts. The sound of the blower kicking in and air rushing through air ducts is normal too.
If you have a newer, high-efficiency furnace that incorporates noise reduction technology and a well-insulated cabinet, you may not notice much sound at all. If your unit has a variable-speed blower motor, it will make minor adjustments in airflow during the heating cycle. The process is not noisy.
If you own a one-stage furnace, the sound of the motor likely is more noticeable.
If your furnace includes an electrostatic air filtering system, you may hear its metal mesh filter zapping pollutants. An occasional zapping sound is not unusual. Continuous zapping may indicate the filter needs cleaning.
What Are Some Unusual Furnace Sounds?
- Humming can sound melodic and calming, but you do not want to hear it coming from your HVAC equipment. If your furnace hums at startup but fails to turn on, it probably has a damaged capacitor. The hum might also indicate the blower is starting to malfunction.
- Squealing points to a blower motor belt issue. It could be worn or in need of adjustment. Bearings in the motor may be worn out or may need lubricating.
- Booming or rumbling could be a sign of dirty burners. The sound is from gas buildup when the burners light. It could lead to a cracked heat exchanger, which could result in a dangerous carbon monoxide (CO) leak in your Des Moines home.
- Thumping usually means the blower wheel or blower motor is out of balance.
- Clicking repeatedly at the start of a heat cycle may indicate an ignition problem.
- Thwapping may indicate debris is hitting the furnace blower fan blades.
Your Next Steps
After hearing odd noises from your furnace, prevent the problem from getting worse. Schedule a tune-up. Midwest Air Pros can recommend an HVAC company in our network to inspect and clean your Des Moines furnace. If a repair is necessary, one of our qualified professionals can do that too.
In the meantime, inspect your furnace air filter and replace if it is dirty. Be sure air returns and heat vents are unobstructed and that registers are open.
If your furnace is increasingly noisy or needs frequent repair, you may want to consider replacing it. Energy Star® suggests replacing your furnace if it is more than 15 years old, with one that has earned its certification.
Schedule Maintenance Today
Your furnace will not make odd noises if it is in top shape and operating at peak performance. Let Midwest Air Pros help you avoid a noisy heating season by recommending an expert HVAC team to maintain and repair your furnace in Des Moines, IA, Omaha, NE, Kansas City, MO, Springfield, MO, and Wichita, KS. Schedule your appointment today.