5 Furnace Noises You Shouldn’t Ignore

A furnace can be a noisy thing.  Luckily, for most of us, we’ve grown accustomed to the unique sounds our heating system emits. You lie in bed at night, waiting to hear the familiar rumble that lets you know all is well and the night ahead will be filled with warm, comfortable sleep.

The regular sounds your furnace makes are a comfort in themselves, letting you know your system is at work, keeping your home warm.  But what about the sounds that aren’t part of your furnace’s usual operation?  Could these sounds indicate impending problems for homeowners?  And just what do these booms, screeches, and crashes really mean?

Below, we’ve outlined five furnace noises you shouldn’t ignore.

Warning Signs Your Furnace Needs Repair

Noises are usually an indication that your furnace needs routine maintenance or repair. However, some noises can indicate an issue with your furnace which could possibly put you and your family at risk. Here is a list of the five most common furnace noises and what your furnace is trying to tell you.

  1. Booming – It’s not uncommon for homeowners to hear a boom when the furnace engages.  In some furnaces, especially older models, a boom could indicate he build-up of gas from a delay in the ignition.  Call a professional service technician immediately, especially if there is an odor of natural gas around the furnace.
  2. Clicking – A clicking noise coming from your furnace is typically an indication of a faulty flame sensor, or possibly a problem between the ignition and the gas.  This will also require immediate attention.
  3. Squealing – Not unlike a car, squealing coming from your furnace could indicate a faulty belt, or possibly, a failing fan motor.  Both fixes are usually pretty routine, but do require a certified HVAC service technician.
  4. Rattling – A rattling sound that doesn’t subside could be indicative of worn or broken components in the motor or fan. If the rattling worsens, you could be hearing the sound of a complete system failure.
  5. Chirping – Chirping noises are common in a furnace that hasn’t been used in awhile.  If you hear chirping, and it’s the beginning of the furnace season, wait a bit.  If the chirping doesn’t go away, you may need your fan belts replaced, or some similar routine maintenance.

Maintenance is Key

Routine furnace maintenance is a must in order to keep your furnace in good working order.  If it’s been awhile since you’ve had your furnace inspected, the sounds you hear could simply be due to your lack seasonal maintenance and not a major problem.

W. F. Smith, Inc. Heating & Air Conditioning can help you decipher the language of your furnace.  When you hear noises that aren’t part of normal operation, contact our professional heating technicians. The longer you ignore these five furnace noises, the more damage could be done to your system.  These not-so-normal sounds can be a red flag that you need service now.

Contact us at the first sound of trouble, and don’t forget to ask about our maintenance plans!


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