Why Is My AC Producing Musty-Smelling Air?

White woman with long pony tails plugs her nose and scrunches her face

When you run your air conditioner, have you noticed a musty, “dirty sock” odor coming out of your air ducts? If so, this is a strong indication that you have mold growth inside your HVAC system.

Below, we’ll explain three typical problems that lead to mold growth in HVAC systems and what you can do about this issue.

Problem 1: A Dirty Evaporator Coil

Your air conditioner’s evaporator coil is located inside the system’s indoor unit. Refrigerant runs through the evaporator coil and absorbs heat from your home’s indoor air, making it cooler. Additionally, the coil collects a lot of moisture from your indoor air during the cooling process.

Over time, the evaporator coil can become caked with dust (a food source for mold). If mold spores find their way into your indoor AC unit, they can get the moisture and dust they need to grow there.

The easiest way to address and prevent this problem is to get your air conditioner professionally cleaned and tuned up annually. Routine maintenance will prevent dust buildup that can lead to mold growth.

Problem 2: A Clogged Condensate Drain Line

Your indoor AC unit pulls moisture from your indoor air during the cooling process. That extracted moisture (or condensate) collects on the evaporator coil and drips down into a drain pan. From there, the water is supposed to leave the drain pan through a pipe called the condensate drain line and leave your home.

Lack of routine maintenance can allow your home’s condensate drain line to fill up with dust and other debris. When this happens, water sits for much longer than it should in the drain pan. That standing water can create an ideal environment for mold growth, particularly if your system is dusty and dirty.

It’s important to schedule a professional maintenance service with a trusted HVAC professional every year to avoid condensate drain line clogs. While cleaning and tuning up the equipment, the technician should also clear the drain line so that water can exit correctly.

Problem 3: Leaky Air Ducts

Many homes in the U.S. have never had their system’s air ducts properly sealed. Along with efficiency and airflow issues, this can also lead to mold problems. When air ducts have leaky joints, gaps, holes, rips, etc., this can allow moisture to enter the ductwork and foster mold growth – especially if the air ducts are already dirty.

If your HVAC system has ductwork, it’s a good idea to get it sealed by a professional. Not only can this help prevent mold problems, but it can help improve your system’s performance by eliminating air leaks.

Winston-Salem Air Conditioning Services

At Logan Home Energy Services, our friendly experts are proud to provide top-tier air conditioning maintenance, repairs, and installations in Winston-Salem and all of Central North Carolina. Experience the Logan difference by calling us at (336) 203-7630 or contacting us online.