Don’t Ignore These 4 Noises From Your Furnace

January 3, 2020

​4 Sounds That Could Result in Furnace Replacement

Your home’s HVAC system is an unsung hero as it works to keep your family comfortable through hot and cold weather. When things are working properly, this finely tuned equipment should operate silently in the background, which is why you should worry if you hear strange noises coming from the unit. While some sounds may be the result of benign situations, others could indicate a problem that necessitates a complete furnace replacement if left unaddressed. Here are four noises you should never ignore when they come from your heating or cooling equipment.


1. Scraping

In a system with moving parts, metal-on-metal scrapes are some of the scariest noises you can hear. Your furnace’s blower fan is a metallic piece that’s surrounded by a metal housing. If you hear a scraping sound, this component could be loose and rubbing up against its casing. It’s important to get a professional diagnosis when you first hear this sound because it’s easily correctable if the damage isn’t too severe. Left unchecked, this situation could result in a complete breakdown of the entire assembly.


2. Squealing and Screeching

Like any motor, your furnace uses belts to turn components such as the blower fan. If the belt loosens or experiences other complications, the result could be a high-pitched screech or squealing noise. While this problem isn’t as severe as metal-on-metal scraping, it could be the first step towards bigger problems.

Another cause of squeals and screeches could be a lack of lubrication between metal bearings and other surfaces. To keep this from happening, have a technician come out every fall to tune up your system before winter hits.


3. Bangs and Booms

A loud boom from your HVAC system could either be a major problem or a simple fix. If your heating system uses natural gas, the bang may be the result of a dirty ignition system that isn’t igniting the fuel. As the combustible material builds up, it eventually lights with a loud boom that sounds like a gunshot and damages your heat exchanger. Only a professional can determine whether the noise is because of this dangerous situation or something less severe such as expanding and contracting ducts.


4. Rumbling

Your furnace should be relatively quiet while it’s running, but a low rumble could indicate a problem. The most likely cause of a rumbling heater is a dirty burner that isn’t operating at peak efficiency. If your burner’s flame is any color other than blue with a slight yellow tip, contact an HVAC professional to clean the system. Ignoring this problem could make the rumbles change into bangs, which are much more damaging to your equipment.


Quietly Enjoy Your Comfort

If you hear any of these sounds after turning on your heating system, call an experienced HVAC contractor for a professional diagnosis. At Next Level Heating and Air Conditioning, we specialize in furnace installation and maintenance throughout Marin and Sonoma Counties, and our experienced technicians are ready to address all of your comfort needs. To learn more information about our company or schedule an appointment for an estimate, give our office a call today at 707-228-9921 or contact us online.


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