Why Does My AC Smell Like Mildew?

For most people, their homes act as a safe haven away from the blistering heat of the hottest days of the Philadelphia summers. They turn their air conditioning unit on and expect to feel the refreshing cooling sensation that comes with a fully functioning HVAC system. However, if you turn on your air conditioning system only to smell the musty smell associated with mold and mildew growth, it can certainly put a damper on your mood. Air conditioning should be refreshing and comfortable but otherwise undetectable. The only thing more miserable than dealing with the hot, sticky conditions is dealing with a foul smell coming from your air conditioning vents.

The last thing you want to deal with in the summer are foul odors coming from your AC that ruin your home’s internal environment. If your AC smells like mildew, mold, or other foul odors, it is time to troubleshoot the problem and perhaps call for professional assistance.

Common Causes For Mildew Smell From Your AC

Mold and mildew odors are some of the most common odors found in air conditioning duct work, and they can occur for a variety of reasons. A properly functioning air conditioning system should overcome the presence of moisture — the building blocks for mold and mildew growth. However, if you have let your regular AC maintenance lapse, these safeguards may not have the capacity to prevent them from worsening. Knowing how to identify these potential issues can help ensure your home is as cool and pleasant-smelling summer refuge as possible. 

Many homeowners may know what mildew smells like, they may not have an idea of where they can find it within their system. Here are the most common causes for mildew odors to occur in HVAC systems:

Dirty or Clogged Filters 

Air conditioning filters are known to be a crucial component of any HVAC system. However, we tend to neglect them most of the time. Did you know that dirty air conditioning filters can lead to mildew growth? The buildup of dust, debris, and other pollutants in your filters can create a breeding ground for mold and mildew to grow unchecked. This can lower your indoor air quality and lead to respiratory issues, along with causing damage to your AC system over time.

Clogged Drip Pan

Maintaining your residential AC system may not be the most thrilling task on your to-do list, but it is essential in keeping you and your family comfortable. One often overlooked component is the drip pan, which collects the moisture generated by your AC unit. When this pan becomes clogged with dirt and debris, it can create the perfect breeding ground for mold and mildew that can quickly spread throughout your system. The buildup can even cause leaks and water damage to your home.

Clogged Condensate Drain Line 

Did you know that a clogged condensate line in your residential air conditioning system can cause a buildup of mildew? This often overlooked issue can lead to unpleasant odors and even respiratory problems for you and your family. If you suspect there’s an issue with your condensate drain line, W.F. Smith Heating & Air Conditioning can help. We can perform regular maintenance and cleaning of your AC system to prevent this problem from occurring.

Moist Ductwork 

Did you know that the moisture that accumulates in your residential AC ductwork can lead to a strong mildew smell? While air conditioning is meant to keep you cool and comfortable, the constant airflow through the ducts can create a breeding ground for mildew if not properly maintained. The moisture from the air, along with trapped dust and debris, can create an unpleasant odor that permeates throughout your home. Luckily, there are ways to prevent this from happening. Regular cleaning and maintenance of your AC system can ensure that your ductwork remains dry and free from mildew, allowing you to enjoy the cool comfort of your home without any unwanted smells.

Internal Problems  

Have you ever walked into your home and been hit with a strong, unpleasant odor? It could be coming from your air conditioning system. Internal problems in your AC, such as clogged filters or dirty coils, can create the perfect environment for mildew to thrive. And let’s be honest, no one wants a mildew-scented home. By regularly maintaining your AC, you can prevent these internal problems and eliminate that unwanted odor. With a bit of care, you can enjoy fresh, clean air once again.

When Do You Need Professional Assistance?

Infographic detailing when a homeowner needs to call in the professionals for AC maintenance

Many homeowners may try to utilize different DIY repairs to help address the mildew smell in their AC system. However, while these options may help in the short term, they don’t always address the underlying cause of your issue. If there’s a problem within your unit that’s causing the mildew growth, you’re only managing a single symptom. 

If you’ve tried the easy DIY solutions like changing your air filters and checking the drip pan for visible clogs with no success, it is time to contact a professional HVAC technician. Many people will first opt to have their ductwork cleaned, but this is simply masking the problem if the underlying cause is not identified. Your technician can survey the situation to determine if an underlying problem needs to be fixed so the smell doesn’t keep coming back.

Schedule AC Repair Service in Philadelphia Today

Homeowners looking for a professional AC repair service in Philadelphia, PA, don’t have to look further than W.F. Smith Heating & Air Conditioning. Since 1946, we have helped countless customers throughout Philadelphia, Bucks, and Montgomery counties figure out what is wrong with their AC system and rid their homes of that pesky mildew smell. We can get to the bottom of your indoor air quality issues and get your system back in good working order in no time. 

Are you tired of smelling mildew every time you tune your air conditioner on in the summer? For help with a mildew smell from the air conditioner in Philadelphia, call the experts at W.F. Smith to clean and fix the problem.

W.F. Smith HVAC testimonial

I’ve been dealing with WF Smith for many years and have found them to be consistently reliable, professional, responsive and courteous. I recommend them without hesitation. I have recently replaced my builders’ grade HVAC (not initially installed by WF Smith) with Lennox products and, though the Lennox products are new on this house, I had Lennox products on my last home in Long Valley, NJ which I had built and was very pleased with their performance there. So, I have every expectation that I will be able to rely upon the product’s performance and manufacturer’s warranties, as well as upon the workmanship that characterizes the installation.