If you’re like most Americans, you rely on a heating system in the wintertime to keep your home nice and comfortable for your entire family. When your system is working fine, you likely don’t give it much thought. However, if you hear a weird noise coming from your heating system, it’s imperative that you take the time to discover what it is.
One of the most common noises that homeowners report hearing from their HVAC system is a banging sound. This can be the result of one of two culprits. One of the most common is a noise described as banging and or popping. This is due to the constant expansion and contraction of your ducting as it becomes hot and cold. In this instance, there’s nothing wrong with your system. It’s just reacting to different temperature changes.
If the banging noise is very prominent and happens every now and then, it could be due to a buildup of gas inside your system’s ignition chamber. Typically, when your thermostat starts up, it will open the gas valve. The igniter will send a spark into the gas to create combustion. When there is an issue with the igniter, it may not create combustion until there’s a large amount of gas filled up inside of the chamber. When the gas ignites at that point, it can create a banging noise that can resonate through the ducting in your home. It’s best to have this problem checked by an HVAC professional.
Another common noise you may hear your HVAC system making when it’s running is a whistling sound. This indicates that there’s trouble somewhere with the airflow for your system. Think of this as similar to whistling with your mouth. As you restrict the amount of area where the air can flow through, you’ll start to hear the whistling noise. Your HVAC system operates in much the same way.
The whistling noise can be created by a dirty air filter that needs to be replaced with a fresh one. It could be caused by a physical blockage in your ducting, such as a rodent or a large accumulation of debris. It could also be caused by closed vents or dampers. It’s a good idea to go through the list of potential reasons to help narrow down and determine what the exact cause of the whistling noise.
One very alarming noise that your furnace may make is a clunking sound. This means that there is a physical object inside of your system that is coming into contact with another object. One of the most commonly experienced culprits of a clunking noise in a furnace is a misaligned fan blade. When the blower fan is not situated correctly, its blades will come into contact with the walls and other parts of your furnace.
Another culprit can be the fan belt. As a belt starts to fray, its split fragments can start rubbing up against other internal components of your furnace. As soon as you start to hear a clunking noise, it’s imperative that you shut your system off. If you continue to let it run, it’s likely that you’re going to cause more damage to the system. This is an issue that you want to have a licensed professional evaluate for you.
As you start to listen more intently to the noises that your heating system makes, you may pick up on a slight humming sound. For the most part, this noise means that your system is operating correctly. Most newer furnaces will make a humming noise when they first start to begin their cycle due to their transformers adjusting the current flow to your heating system.
However, if the humming noise continues to stick around when your furnace has been operating for a while, it can be a cause for concern. This loud humming noise could be caused by the blower motor starting to deteriorate. It could also be caused by a fan that is starting to deteriorate. If you notice that your furnace continues to hum even after it starts up, you should have a licensed HVAC professional come in and evaluate the sound further.
One very distinct sound that will create a lot of alarm is a scraping noise. This will come on suddenly and be very prominent. The most likely culprit is that one of the internal components of your furnace has become loosened. This could be the blower fan motor that is loosening so much that its blades are dragging against the casing of your furnace. The best thing to do in this situation is to completely shut off your heating system to prevent further damage and contact a professional to further assess the issue.
Somewhat similar to a scraping noise, you may hear a higher pitch chirping noise when your heating system is on. If this chirping noise happens right at the beginning of when your furnace fires up, it could simply just be part of its normal process when the weather is cold outside. However, if you notice that the chirping noises are consistent throughout the entire time that your heating system is running, it’s an indication that there’s something awry.
A common culprit is that the pulley for the blower motor is out of alignment. The chirping noise that you hear is likely metal against metal. In this type of situation, it’s best to call in an HVAC professional to further evaluate the issue and resist the urge to run your system until they get there.
One noise that may be quite disturbing when you first hear it is a rattling sound coming from your heating system. In some cases, your furnace may make a rattling noise when it first starts up. This shouldn’t be alarming. However, if your system consistently makes a rattling noise throughout its entire operation, then it’s a sign that there’s something wrong.
The most likely culprit is that there is a loose panel cover that is rattling back and forth as the system runs. Fortunately, tightening the bolts on the panel can help to alleviate this problem. If the panel wasn’t the source of the issue, then it’s best to call in an HVAC professional to further assess the source of the noise and get it remedied before it creates more damage to your system.
One concerning noise that your heating system may make is a low rumbling sound. If this sound persists after your furnace has run through its cycle and switched off, it can be extremely dangerous. You want to shut your system off and call in an HVAC professional. The most likely problem is that the oil or gas that powers your furnace remains in the combustion chamber after your furnace has already completed its cycle.
Reliable Heating Service
Aace's Heating, Air Conditioning & Swamp Coolers is proud to serve Victorville, CA, and the surrounding areas. We can assist with all of your heating and AC repair, installation, and maintenance needs. We also work with swamp coolers and offer a maintenance plan to keep your systems up and running optimally. Simply call us today to get help from one of our highly experienced, NATE-certified technicians.