3 Strange Smells Coming From Hvac Vents And What They Mean


When your heating, ventilation, and air conditioning system turns on, the first thing you expect is an immediate influx of heated or cool air; however, there are instances in which strange odors greet you first.

There are both hazardous and non-hazardous smells that may be emitted from your HVAC system; however, regardless of whether or not they pose a danger to your immediate health is not always a concern.

Unusual smells and odors may make you very uncomfortable. They may make it difficult for you to relax in your own home. Smells and odors may result in your refraining from accepting guests into your home.

All in all, any smell or odor that comes from your vents is considered to be “bad” in one way or another. In this detailed post, you will learn what those smells and odors may indicate.

Electrical Smells

Does your HVAC system smell as if it is overheating or as if wires are burning? If so, this is a cause for concern. You should immediately cut off the power to the system. This includes the power at the thermostat as well as the master breaker/fuse/switch.

In most instances, this indicates that the unit is overheating, the wiring may be experiencing an issue, or that the motor to the unit may be in distress.

In some instances – in the case of turning on the heat – it could be the result of dust burning off in the system; however, you should never take the chance. Seek professional assistance for an inspection as quickly as possible.


If you observe a smell that resembles sulfur or rotten eggs, this could mean that there is a gas leak. It should be known that natural gas does not have a smell; however, providers of this substance add an aroma within the gas so that it is easy for their customers to indicate a leak or other complication.

If you find that this smell is coming from your vents, you should open up all windows within the home, immediately leave the structure, and contact your gas utility company. If the gas company gives an all-clear, contact a professional HVAC technician for assistance.

Mold or Mildew Smell

When a HVAC system is in operation, there is a massive amount of condensation that blows around. In most instances, it escapes through moisture drains; however, there are cases where the system does not drain appropriately.

The condensation builds up in the system and then results in the development of mold and mildew. This will require professional duct cleaning.

Failure to clean the system of mold and/or mildew and to correct any drainage issues could result in the development of many health-related complications, such as allergies and breathing difficulties.

We Take Care of Unusual Smells and Odors

Here at Ronald Smith Heating & Air, we have the training, skills, and licensure necessary to handle any and all unusual smells and odors coming from the vents of your HVAC system.

Once you schedule services with us, we will quickly dispatch one of our certified technicians to your home to identify and correct the issue that you are experiencing.

For more information, contact us today by calling: 770-766-9212

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