Here in the Plainfield/Naperville area, we tend to run our air conditioners daily through the hot and humid summers and the furnace runs constantly during the cold winters.

The HVAC unit takes a lot of wear and tear.  Occasionally, there are some issues that can arise.  Unpleasant smells or strange noises may signal the need for a repair or replacement.

The most common components in the HVAC system that can cause odd smells or strange noises are the compressor, driveshaft/fan blower, and the fan blade.  Issues with these components require a professional service call.

If you are experiencing any weird smells or sounds and do not know if it is normal or not, here are a few of the more common noises and smells and if/when to call for help.

No Sounds of Silence


Chirping sounds are typical with a furnace and are usually just the natural noises associated with the mechanics of the unit.


Rattling noises are common when the unit is cooling down and is not usually cause for alarm.


Pinging sounds can be caused by expanding or contracting air ducts are not typically a major worry.


Humming occasionally occurs when the furnace burner light and is no cause for alarm.


Booming is common when the weather heats up or cools down, causing the ductwork to expand or contract and can be normal.  However, when a booming sound is accompanied by a burning smell it is likely there is a dirty burner in the furnace or a defective gas valve.  A professional inspection is recommended for this issue.


Whining or vibrating noises can signal a problem with the furnace and a professional inspection is recommended.


A clunking or bumping noise typically indicates a cracked belt and the need for replacement.  Call a professional to inspect this and make the repair.

Stop and Smell the Roses


A musty smell could signal mold or mildew in the ductwork.  Changing the furnace filter will help, which is easily done without a service call.  Additionally, cleaning the drip pan with bleach or white vinegar is recommended, which can also be done without a service call or, if you aren’t sure where the drip pan is located, call a professional for service (having an inspection of the system will also hep prevent any other issues from popping up.)


A burning smell can indicate a dirty burner or a defective gas valve and requires a call to a professional.

Award-winning Service You Can Count On

When you need HVAC services, it pays to hire a company you can depend on. Call TR Miller Heating & Cooling at 815-265-6650 to request an immediate appointment in Plainfield, IL, and the surrounding areas.

Homeowners know they can count on TR Miller Heating & Cooling to get the job done right the first time. As a third-generation company, we have the experience to know what works and what does not.

Source:  American Standard Air

company icon