Why Is My Furnace So Loud?

Your heating system is supposed to keep you warm, not keep you awake with a chorus of banging and clanging. When it’s working properly, your furnace should make nothing more than a light blowing noise when it’s on, and perhaps a click or two when it first switches on or off. If it’s playing you an entire concert, there’s something wrong!

Let’s a look at some common causes of noisy furnaces and what those sounds can indicate about your system’s performance.

Reasons Your Furnace Could Be Making Noise

Failing Motors or Motor Belts

The motor in your blower unit has a belt that keeps it running. If you’re hearing a squeaking, squealing noise as you furnace runs, the motor belt may be loose or fraying. A loud scraping sound that sounds like metal rubbing against metal can also be sign of motor malfunction. The blower wheel could be loose or broke, or perhaps the entire motor has become detached from the furnace housing. Any of these problems will need to be addressed by a professional.

Dirty Burners

Does a loud “bang” make you jump every time the furnace turns on? The furnace’s burner might be dirty, and the dirt might be slowing the ignition process, causing a good deal of gas to build up before it finally lights with a little explosion. Have your HVAC technician come clean the burner. Then, take some steps to keep the burner cleaner, going forward. Make sure you change your furnace filter every month. (Set an reminder in your phone so you don’t forget!) Make sure your furnace cover is on, and vacuum out your vents every few weeks to reduce the amount of dust that makes its way into ducts.

Dry Bearings

If the furnace is making a high pitched whining noise, it’s not just throwing a temper tantrum. The bearings may need to be lubricated. If you have your owner’s manual and can locate the lubrication ports on either end of the shaft, you can attempt this step yourself. However, if you’re not completely sure you’re lubricating the right part, ask your HVAC tech to help.

Air Ducts Expanding & Contracting

Are the noises you’re hearing occurring mainly during the first few minutes after the heat turns on, and then again once it turns off? Do they sound like they’re coming from within your walls, rather than from the furnace itself? Your ducts might be expanding and contracting in response to the change of temperature that occurs when heated air flows through them.

This can be a tough situation to fix. You may need wider ducts, or you might need to have some of the ducts better insulated. However, this is not usually a serious or dangerous issue, so as long as you don’t mind living through the banging and cracking, there’s not an immediate need to spend thousands fixing it.

A Faulty Thermostat

Most heating systems make a “click” when the thermostat activates them to turn on. If you’re hearing repeated clicks rather than just one, this could be a sign that your thermostat is not working as it should. Try changing the batteries, as faulty batteries can sometimes cause issues like this. If you’re handy, you can turn off power to the thermostat and then remove it from the wall. Ensure the wires in the back are all connected securely. If everything is hooked up properly and you’re still having issues, it’s time to call the pros.

Call Peninsula to Repair Your Noisy Furnace

Of all things to keep you up at night, your furnace should be the last! Call Peninsula sooner rather than later to get the noisy issues fixed before they cause more serious damage in your Delaware or Maryland home.

For furnace repair services, day or night, call Peninsula at 302-629-3001 or contact us online today


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