The buildup of dirt and debris: The blower wheel and fan blades may get covered in dirt and other particles over time, creating an imbalance that produces loud noises. Your blower wheel component within your furnace will need to be cleaned by a professional technician.
This cracking, sometimes groaning sound is the sound of the heat exchanger expanding when the burner is on, and contracting when the burner has stopped. It is normal, and nothing to be concerned about.
Loud Bangs, Rumbles, Knocks, or Booms
Loud noises like this are a sign of a build of gas in a furnace. The noise you hear can mean your heat exchanger is at risk of cracking. Even worse, it's a sign that something dangerous could happen if you continue to use your heater.
Thumps and bumping noises, like an unbalanced washing machine, often indicate an unbalanced blower wheel or motor. This is a serious issue that requires immediate HVAC repair. The blower wheel and motor are major furnace parts and you don't want them bouncing around.
A low rumble is a normal sound when your gas or oil-fired furnace kicks on. However, if that rumble is louder than usual—or lasts longer than usual—this could indicate a very serious problem with your burner.
If your furnace suddenly produces loud, sudden banging or booms, you should call an experienced technician as soon as possible. These sounds could indicate stuck ignition, a potentially dangerous situation involving carbon monoxide which is deadly.
You'll probably have to remove an access plate to get at the ports. If the blower has grease cups instead of oil ports, remove the screw caps that cover the cups and fill the cups with bearing lubricant, which is available at automotive and hardware stores. When you lube the motor, you should also check the belts.
Tighten the motor mounts and see if that solves your issue. If it doesn't, insulating the blower might be the best solution. If that doesn't work, then you may need to replace the whole blower. If the annoying sound is a screech, you might just need to oil the blower motor.
First, know if you have a gas, electric or oil furnace. Electric furnace installation tends to be the least expensive, ranging between $3,000 and $7,000, according to HomeAdvisor. Installing a natural gas furnace falls in the range of $3,800 to $10,000, and an oil furnace ranges $6,750 to $10,0000.
One of the most common furnace problems is a malfunctioning thermostat. A sure sign your thermostat isn't working properly is if your fan is constantly running. This will cause your thermostat battery to run, and cause your furnace to work inefficiently.
If your furnace is making an obnoxious noise, it's likely because the furnace blower motor is turning on and off as part of normal heating furnace cycles. Make sure your thermostat is set properly to the desired temperature and off when you don't need heat (like overnight).
While costs can vary, homeowners can typically expect the following range: Standard Blower Motors: These might cost between $400-700, excluding labor. Advanced Multi-Speed or Variable-Speed Motors: These are generally more expensive, with costs ranging between $650-1250, not including labor.
Typically, a gurgling noise is most commonly caused by trapped air in your radiators, although it could also mean a frozen condensate pipe, water shortage in the header compartment, or low water pressure. Sometimes, gurgling sounds are just the hot water moving in the heater and not a reason to worry.
On a normal day, your home's furnace might make a little noise as it starts up, when it's turning on, and then when it turns off. You can always expect to hear some noise from the furnace. The thing about this noise is that it should never be disruptive.
7. Grinding, Scraping, or Clanking. If your furnace sounds like a train grinding and scraping away on tracks, then you probably have an issue with the blower wheel.
The Average Furnace Lifespan
A well-maintained furnace can last at least 15 to 20 years, but completing annual maintenance and being diligent with repairs can extend its life even longer.
Your base homeowners policy will cover many types of damage to your furnace. An extra endorsement known as Equipment Breakdown Coverage (EBC) will give you additional coverage for certain types of mechanical or electrical failure.
Identifying the Priciest Component: The Heat Exchanger
Due to its complex role, a failure or crack in the heat exchanger can lead to serious issues, including dangerous carbon monoxide leaks. This makes furnace repair essential to maintain safety and functionality.
If your furnace produces a loud humming or buzzing sound, there could be an issue with the motor. There may also be something wrong with the fan. It can be something as simple as a loose screw, loose door, or improperly installed furnace filter.
A loud buzzing noise almost always indicates that your furnace is working hard to generate warm air. This may mean that its blower fans are extremely dirty or that the motor powering the furnace fans is beginning to fail.
For 1- to 2-inch filters, replace them every 1 to 3 months. For 3- to 4-inch filters, replace them every 6 to 9 months. For 5- to 6-inch filters, replace them every 9 to 12 months.
Check all belts and replace any that are damaged or worn out. Also, check for loose screws in both fans and vents and tighten them if necessary. If your furnace uses two separate fan units (one on each side), be sure to check the screws on both of them.
One of the more common problems in a blower motor is the bearings. Bearings surround the motor shaft, allowing it to run smoothly at high RPM with almost no friction. When the bearings go bad, the motor may make a grinding or screeching sound, or not run at all because of the friction preventing the motor from turning.