When your Mentor, OH furnace turns on and runs for a short period of time, you’ll notice some normal sounds. This can include the click of your system starting and maybe the low hum of your furnace operating. You will then start to hear air coming through your ductwork and vents. However, there are several abnormal sounds that can indicate a problem with your furnace. Let’s look at some of the most common reasons your furnace is making noise and what you can do about it.
1. Wiring Issues
Wiring issues typically produce buzzing or zapping sounds when your furnace is starting up or running. If there is a problem with the flow of electricity within your HVAC system, this can cause a risk of electrocution or fire. Several wires run through your furnace and beyond, connecting equipment to your breaker panel, thermostat, blower assembly, and more.
We will check all your wiring for signs of damage. There may also be a problem with the insulation of your wires, which can result in a buzzing sound. If two bare wires are touching, this is also an issue that we need to address immediately.
If you suspect an electrical issue is occurring with your furnace, turn the unit off immediately and call us for furnace repair.
2. Capacitor Problems
Your furnace has a capacitor that functions as part of the startup process. It is connected to a power source and is used frequently, which can lead to wear and tear on the capacitor. A power surge can also cause damage to the capacitor. Also, a capacitor can get nudged out of its spot because of movement generated by the internal motor.
This is another problem that often produces a buzzing or humming sound. If the noise is only heard during startup, this often indicates a capacitor issue. The noise will typically go away once the furnace is running.
Capacitor issues can often be spotted with a visual inspection. If there aren’t any loose or damaged wires, a multimeter can be used to test the capacitor.
3. Blower Motor Malfunction
Your furnace has a blower motor that connects to the blower fan and capacitor. A blower motor can make a variety of abnormal sounds depending on how severe the problem is. A slight buzzing sound can occur, or a louder grinding or screeching sound may also be present.
Physical damage can occur to your blower motor if it malfunctions. During an inspection, we’ll look for any damage to the wires or connections coming from the blower motor. We may want to test the blower motor independently from your furnace. This involves removing the unit and connecting it to an exterior power supply to see if the noise can be recreated.
4. Transformer Noises During Runtime
A furnace transformer is an important component of the startup process. The purpose of this part is to regulate the amount of voltage that is being supplied to the furnace. If it malfunctions, this can impact heating and cooling or short out your system entirely. You could also experience a power surge from too high a voltage. High voltage can produce a buzzing sound. You may even hear that sound continue when your furnace is no longer running.
We will check your transformer to see if it is malfunctioning or not connected correctly. Because issues with your transformer can produce sparks and electrical conduction, we advise that you utilize a professional. Something as simple as the screws on the transformer box being loose can cause a buzzing or humming sound, but you can’t be too safe when dealing with electricity. Issues with it can often be fire risks.
5. Ignition Control Board Startup Failure
The ignition control board module is a key part of furnace startup. If you hear a clicking sound but your furnace doesn’t start to run, this could indicate an ignition control board problem. You may also be experiencing a problem with dirty burners or a burnt-out pilot light (in older furnace models).
6. Small Explosions
Explosion isn’t a word that you want to hear regarding your furnace, but this can occur during startup. If there is a gas buildup inside your furnace and then the system ignites, this can cause a loud banging sound or whooshing noise. Issues can include a poor air-to-gas ratio, dirty burners, and a low gas supply.
7. Cracked Heat Exchanger
If your heat exchanger is cracked, this can release carbon monoxide into your residence. It’s important to have carbon monoxide detectors throughout your home in case of a furnace malfunction, but there are sounds to listen for as well. A cracked heat exchanger can produce rattling or rumbling sounds, particularly during the first part of the startup process.
It can be quite expensive to repair a cracked heat exchanger. Also, there’s a safety component to worry about with this malfunction. We normally recommend that you replace your furnace if this is an issue you’re experiencing. This is the safest option for you and your family.
8. Bad Bearings
Bearings are in a few different locations within your furnace. They can start to make a lot of noise as they get older, producing a grinding, clunking, or squealing sound during runtime. They can also produce a very high-pitched screeching sound that you won’t be able to ignore. This issue is often easy to repair if nothing further is going on.
9. Dirty Air Filter
A lot of homeowners neglect to change their air filter regularly. While this can decrease the efficiency of your HVAC system and reduce the quality of your indoor air, a dirty filter can also impact the noises coming from your furnace. As air tries to force its way through a dirty filter while your furnace is running, a whistling or whooshing sound may occur. These sounds can also come from things like damaged ductwork or vents that are closed.
It’s important that you always maintain adequate airflow through your HVAC system. We recommend changing your air filter once every 30 to 90 days, depending on the type of filter you’re using. More frequent filter changes may be in order for people with allergies, homes with pets, and during times of high pollen. Avoid using a filter that is too high of a MERV rating for your specific furnace. High-MERV-rated filters can really restrict airflow if you don’t have enough power coming from your system.
If you hear odd noises coming from your furnace, reach out to our team here at Anderson Heating, Cooling, Plumbing & Electric in the Mentor and Cleveland areas. We can quickly diagnose any issues and provide fast repairs so your furnace can run safely again. We also install, repair, and maintain all kinds of heating equipment and air conditioners, service water heaters, sump pumps, drains, sewer lines, and garbage disposals, in addition to offering a full array of electrical services. This includes new wiring, rewiring, electrical upgrades, breaker panel repairs, generators, and more. Contact Anderson Heating, Cooling, Plumbing & Electric to schedule an appointment today.
