We may not pay attention to our heating system until it stops working or strange noises start to come from the furnace. Without a reliable furnace, your house could quickly become an uncomfortable and even dangerous place to be. The home’s furnace could become even more concerning when you start hearing strange noises coming from your furnace. Since a furnace is a complex piece of machinery, it can be somewhat intimidating to try and figure out where the noises are originating. By understanding the various noises coming from your furnace and furnace issues that could cause those noises, you will know when you need to call a professional HVAC technician.
Squealing from the Furnace
One of the more annoying furnace noises that you might hear is squealing. In many cases, squealing originates in the blower fan instead of the furnace itself. The blower fan rotates on two bearings, which can wear down over time. When one or both of these bearings wear out, it allows metal-to-metal contact in the bearing housing. Then, as the blower fan spins, this contact causes a high-pitched squealing noise from the furnace. If you have a belt-driven fan, squealing can also happen if the belt is wearing out and beginning to slip.
In some cases, a furnace squeal can be corrected by adding grease to the furnace bearings. That’s why it’s important to have a professional HVAC contractor inspect your system to see exactly what needs to be done.
Grinding Noise from Furnace
Another noise you might hear while your furnace is running is a grinding-type noise. As with squeaking noises, grinding noises often originate in your blower fan. If the fan becomes dirty or the bearings wear out, the fan can become misaligned in its housing. Then, when the fan is spinning, the individual fan blades can scrape against the housing, resulting in the grinding noise you hear.
When a blower fan grinds, it can lead to significantly reduced efficiency because the fan won’t be able to move as much air. This means your system will have to run longer to change the temperature in your home, thus lowering the efficiency of the system and costing you higher energy bills. On top of that, when metal is grinding on metal, it can permanently damage your fan and require you to invest in a new fan before you can continue using your furnace.
Popping Noise from Furnace
In many cases, a popping noise coming from your furnace isn’t a huge cause for concern. That’s because popping sounds can occur when your system’s components increase in temperature at the beginning of a heating cycle. Metal components in the heat exchanger and ducts are especially susceptible to pops caused by temperature changes. If the popping noises go away after your furnace runs for a few minutes, that’s likely the cause of the popping noise from your furnace.
But if the popping is caused by a furnace issue, you should call a professional technician. If the popping noises continue for the entire heating cycle, you may have a dirty furnace burner that can’t correctly ignite. Another common furnace issue is the possibility of a crack in your heat exchanger, causing it to transfer heat in an abnormal way. If you’re concerned about the popping noises that your furnace is making, you can always call for the help from our professional heating services to determine the seriousness of the furnace noise.
Furnace Rattling
If you hear a rattling noise coming from your furnace, it’s important to have it looked at right away by a heating specialist. Typically, your furnace will produce a rattling noise when a bolt or screw is loose somewhere on the system. The problem is that finding that loose screw or bolt can be kind of tricky. This is especially true if the loose component is located in the interior of your furnace. In some cases, the culprit may be as simple as a loose furnace cover that needs to be fastened more securely. However, it could also turn out to be screws that are holding a critical circuit or sensor in place. In those cases, the rattling noise from the furnace could cause more harm to the system.
Furnace Booming
Of all the different furnace noises on this list, probably the most worrisome is booming. When you hear small booms coming from your furnace, it can sound as though your furnace is about to explode. Surprisingly, the cause of a booming noise does often involve explosions, though not of the house-destroying type. When your furnace begins its heating cycle, it relies on the pilot light to ignite the gas as the gas enters the burner. However, if there’s a problem with either the burner or the pilot light, excess gas can accumulate in the burner area. Then, when the burner does finally ignite, a small explosion will happen in the burner box as the excess gas burns away.
To prevent further furnace issues, it’s important to have an experienced HVAC technician clean your burner and inspect your pilot light to ensure both components are working properly. This will help prolong the life of your furnace and ensure that you and your family stay safe.
Clicking Noise from Furnace
Your furnace relies on a series of electrical relays to begin and end the heating cycle. Sometimes, you’ll hear these relays make a clicking noise when they first engage. Although it might sound concerning, this is completely normal. However, if you notice the clicking noises continuing, then you likely have a problem on your hands.
Typically, repeated clicking noises happen because the broken relay is still trying to engage but isn’t sending electricity where it’s needed. If you have a bad relay, it’s unlikely that your furnace will turn on, so you’ll want to address this problem quickly to keep your home comfortable.
What To Do if You Hear Strange Furnace Noises
Anytime you face a furnace problem, taking quick action is important. Ignoring the problem will often cause the affected components to cause harm to nearby components that were previously functioning correctly. This will result in a larger repair bill and potentially more time spent without a furnace. So, while it may not be the first thing you want to spend money on, it’s still important to make the investment on getting your heating system maintained regularly and repaired promptly.