6 Furnace Sounds That Require Immediate Attention

There was a time when furnaces used to make a lot of noise. Thankfully, the new-age furnaces are far less noisy. And so, if you hear any unusual sound coming from your furnace, you must pay immediate attention to it. A furnace noise could be a warning sign of an upcoming problem that can be easily avoided if acted upon on time. On the other hand, ignoring an unusual furnace sound can lead to costly repairs. On that note, let’s take a look at the six different furnace sounds that you should never ignore.

Metal Scraping

Never ignore if you hear a metallic scraping sound like metal scraping against metal, grinding gears, or nails on a chalkboard. The metal scraping sound might indicate that there’s a problem with the blower wheel of the furnace. Chances are that the blower wheel has come off loose from the motor shaft, and it is brushing against or hitting the blower housing. Turn off the furnace immediately to avoid further damage and schedule a furnace repair in Puyallup. If the blower wheel has come off loose, the technician will simply tighten it up. But if the blower wheel or the motor mount is broken, you will have to get it replaced.


Rattling is another common warning sign that indicates a furnace problem. Usually, a rattling sound is caused by loose bolts in the access hatch. You can easily tighten the screws yourself with a wrench. Just make sure the furnace is turned off before you fix it. Another reason behind the rattling sound could be a cracked or fraying blower motor fan belt if the fan belt is broken. Call up an HVAC contractor in Auburn, WA, and have the fan belt replaced. Besides the aforementioned reasons, a dirty burner might also lead to a rattling sound. Since the burner is connected to the gas line, it’s best to have the furnace inspected by a residential HVAC expert in Tacoma.

Loud Bang, Boom, or Pop

If you hear a loud bang or pop sound on turning on your furnace, it’s either an air duct issue or your furnace burners are dirty. It’s not unusual for the air duct to expand when heated and contract when cooled. If your air ducts are small or weak, they will make a loud bang or pop sound. But sometimes, even a quality air duct might make a bang or pop sound. That’s because the vents are closed or the air filter is clogged. Besides air ducts, dirty burners can also lead to bang-and-pop sounds. When the burner is dirty, it doesn’t light up immediately, and the gas that’s getting supplied to the burner begins to build up. And so when the burner ignites, the gas that’s built up gives a pop-up sound. This can be quite dangerous, and you must schedule an HVAC contractor visit in Auburn, WA, to have the issue fixed as soon as possible.
Note: In the long run, these explosions can lead to a crack in the heat exchanger, and you may end up paying for a costly repair.

Screeching or Whining

Is your furnace making a high-pitched whining or screeching noise, just like a car does when it has a loose belt? One of the most common causes of a whining or squealing furnace is a loose belt. And while it may not sound like a big deal but if not repaired on time, it can lead to bigger issues such as a broken belt or damaged blower motor. And in that case, replacing the belt or the blower would be the only solution left. A furnace might also make screeching or whining sounds because of a dry shaft bearing that needs oiling. To avoid such issues, you must go for regular furnace maintenance in Tacoma, WA.


The potential reasons for that scary loud rumbling sound coming from your furnace may range from minor issues, such as a dirty burner or dirty draft inducer, to major issues such as a cracked heat exchanger. You might also hear the rumbling sound because of loose furnace panels that tend to bang against the furnace. The issue might also occur because of a pilot light ignition issue. Whatever the reason, it is advisable to have the problem fixed at the earliest to avoid any costly repairs at a later stage.


If your furnace is clicking, it could be a potential ignition system malfunction or internal part damage. For instance, if the sensor is dirty and covered with dirt, grime, or soot, it doesn’t trigger gas flow, and in the meanwhile, the spark igniter continues clicking. The same thing happens when there’s no gas supply because of a faulty gas valve that won’t open. Besides these ignition system problems, the clicking may also be caused because of damage to an internal part such as the fan, motor, electrical component, or duct. Whatever the reason, you need an HVAC contractor in Auburn, WA, to diagnose and repair the problem.

Ignoring furnace issues can lead to sudden breakdowns and might also require you to go for an early heating replacement in Bonney Lake. To avoid such issues, ensure a timely furnace repair or service as soon as you start experiencing a furnace problem. If you are looking for an HVAC contractor in Puyallup, Auburn, Tacoma, Bonney, or nearby areas, get in touch with us at Rainier Heating & Cooling. You can call us at (253) 600-2758 or drop us a line at

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