Hansen Super Techs | HVAC, Electrical & Plumbing Mobile AL
Home » Furnace » Troubleshoot why is my furnace making a high pitched noise?

Troubleshoot why is my furnace making a high pitched noise?

Oct 29, 2023 | Furnace

You turn on your furnace to warm your home, and a strange noise follows. Obnoxious, loud, and consistent, it’s slowly driving you insane. You’ve discovered the noise is coming from your furnace, but you don’t know why. 

Understanding why your furnace is making noise can help you troubleshoot the issue. There are several possibilities for why this is happening. This may be the first time you’ve heard this sound. It’s quite normal and occurs on occasion with some furnaces. 

While not a cause for concern, it’s still nice to know what’s causing the sound. Below are some of the reasons why your furnace is making noise and how to troubleshoot it before calling Hansen Super Techs to assist. 

1. The Blower Motor Bearings or Wheel May Be Bad

The blower wheel is responsible for blowing air through the furnace and into your home. A bad blower wheel can cause the loud, high-pitched sound you’re hearing. The good news is it’s an easy fix if this is the problem. You can replace it yourself or call a technician to come out and do it for you. A bad motor can also cause an annoying noise. If the motor is hitting the housing, you’ll hear a clicking sound. A motor that’s either too loose or too tight can also cause this. The good news is it can be fixed by tightening or loosening the belt that drives the motor. If the bearings are bad, you’ll hear a grinding sound.

2. The Burner Ports May Be Clogged

If air isn’t being sucked in through the intake ports, it will have to be forced in through other means. A clogged intake port will create the hulking sound you hear. You can usually resolve this problem yourself by cleaning out the ports with a wire hanger or screwdriver, and this should only take a few minutes to do.

3. The Heat Exchanger Malfunctions

The heat exchanger is a metal pipe that sits between your furnace and the heater. The role of the heat exchanger is to transfer heat by the combustion of to the air that circulates through home’s vents. This part of the furnace is designed to function quietly, but will make humming, rattling, or banging noise when it has any of the following problems:

  • Loose or damaged parts
  • Not enough air flowing through the system
  • Dirty or clogged heat exchanger
  • Old age of the furnace
  • Blower motor issues

These issues are very common in older furnaces that are coming to the end of their lifespan. If your furnace makes similar noises, it may be time for a professional inspection from an HVAC technician.

5. Issues in the Air Handler

A high pitched whistling sound or banging noises can also be due to a malfunctioning air handler. Because it is in charge of distributing all the air, any little malfunction will result in a terrible sound for the whole house to bear. Here are some air handler issues that can lead to great annoyance:

  • Loose or damaged components
  • Dirty or clogged components
  • Fan motor problems
  • Issues with air ducts
  • Dirty air filter

6. Dirty Thermostat

If the thermostat is making a clicking noise, it could be because the contacts inside are loose and touching. If so, tighten the screws, and it should stop making noise. If there is dirt or corrosion on the contacts, you’ll hear a clicking sound as well. You can easily clean them out with a pencil eraser to fix this problem.

If you hear a clicking sound and an abrupt stop to the operation of the furnace, there may be an issue with short cycling. Additionally, if the thermostat is flashing an error code, you will need to contact a professional furnace repair technician for assistance.

7. The Blower Motor Is Bad

If your motor makes a grinding noise or if the bearings are bad, the motor is probably bad and will need to be replaced. If this is the case, we’ll recommend replacing it with a new high-quality motor. For furnace maintenance, repair, and installation  in Theodore, AL, and surrounding areas contact Hansen Super Techs. We offer reliable, affordable heating and air conditioning services designed to keep your system running in top condition.

8. Condensation Is Forming

Condensation in the air ducts can be another cause of furnace noise. Condensation occurs when warm, moist air is forced through the metal tubing. When the air comes into contact with cooler metal, it turns into water. This can cause a lot of noise if it isn’t corrected. If this happens, turn off the furnace and leave the doors open to allow for ventilation for it to dry out completely.

9. The Regulator Is Bad

If your furnace is set to a lower setting, it may be making a humming sound. This is because the speed of the blower motor is being regulated. If the noise is constant, you might have a problem with your regulator. If this happens, call us to come out and fix it for you.

10. The Limit or Safety Switch Is Bad

The limit switch determines the temperature of the furnace. If it’s bad, it can cause your furnace to make an odd noise. The good news is that this is usually an easy fix that only takes a few minutes to do. If it’s not, call us to come out and fix it for you.

11. The Burner May Be Broken

If the burners are loose or making a squealing noise, they’re probably bad. If this is the case, we’ll have to replace them. If you hear any of these noises coming from your furnace, you’ll need to call us right away. We’ll be able to diagnose the problem and let you know what needs to be done. We may even be able to fix the problem ourselves if it’s a quick fix.

12. The Condensation Drain Is Blocked

Condensation drains are designed to get rid of moisture that causes problems for your furnace. If your condensation drain is blocked, moisture can’t get out of the machine. When this happens, the condensing unit will overwork itself to heat your home. This can cause metal parts to move around inside, which can cause an annoying noise. If this happens, you’ll need to have it cleaned out properly.

Are You Dealing With Furnace Noise?

The best course of action to take with furnace noises that don’t go away is to call a professional who will help get to the bottom of the issue. Contact Hansen Super Techs today who will inspect the furnace, fixing what’s broken and eliminating those noises. Restore the comfortable ambiance of your home with the help of our technicians today!