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Musty Smell in Your HVAC? What You Can Do About It

Dirty Air Filter

Now that winter is over and spring is turning into summer, many people in the Greenville, SC, area are starting to turn on their air conditioners for the season. If you've recently turned on your HVAC system and have realized that your air conditioner smells musty or moldy, this needs to be addressed before the cooling season starts in earnest. 

What Causes a Musty Smell in Your HVAC System?

Musty smells can happen when mold spores invade the ducts in the home. Often, this happens in homes that have high humidity, poor ventilation, or a tight building envelope. Modern homes may be more susceptible to humidity problems than older homes because modern insulation and building envelope practices can trap moisture in the home. Occasionally, high humidity occurs because of plumbing leaks. 

Musty smells can also occur because of pest problems. Rodents that build their nests in the ductwork of the home may spread a musty ammonia smell that is unpleasant and somewhat similar to mold.

What Can You Do to Treat a Musty Smell in Your HVAC System?

First, it's important to be certain whether the smell is coming from the ducts. Start by airing out your home. Open the windows to let in some fresh air. You may need to place some potpourri in the rooms of your home and run some fans.

Once the smell is gone, close the windows. Wait a while before turning on the air conditioner again. If the smell returns without running the HVAC system, this could be a sign that the smell is not in the ducts. If the odor doesn't return until you turn on the air conditioner, this is a good indication that the smell is coming from the ducts. 

Once you're certain that the smell is coming from the ducts, it's time to call an HVAC professional. The HVAC professional will need to inspect your system to find the cause of the scent. Depending on the problem, they may suggest cleaning the ducts or making repairs to the system.

If the problem has occurred because of a rodent infestation, certain parts, such as chewed-up wires or damage coils, may need to be replaced. If the ducts themselves are dirty or moldy, they will need to be cleaned. 

How Can You Prevent Mold From Growing in Your HVAC System?

If mold is a problem, steps need to be taken to avoid this problem again. Moisture problems that go untreated will contribute to continued mold growth. Have a plumber check your home for any significant leaks that could be causing mold to grow in your vents. If a leak isn't the problem, then humidity may be the issue. 

Some ways to reduce humidity in the home include:

  • Run a dehumidifier. Install a centralized dehumidifier, or run a portable dehumidifier in the affected rooms of your house.   

  • Use the air conditioner often. Air conditioners naturally reduce humidity in the air. 

  • Use the vents. Running the kitchen and bathroom vents after cooking or bathing can help remove moisture from the home.

  • Unblock attic ventilation. Blocked attic vents can trap moist air in the home; unblocking these vents can help. 

Following these tips can help reduce humidity in the home and reduce the chances of mold growing in the home. 

Where Can You Turn With More Questions?

If you have more questions about musty smells in your HVAC system and what you can do to prevent them, contact your HVAC professionals in Greenville, SC. At B & K Services, we're happy to answer any questions you might have about unpleasant smells in the HVAC system.