How to Get Rid of Mold in Your AC Air Handler

14 May 2020
 Categories: , Blog


If you get a whiff of mold or mustiness but you can't figure out where it's coming from, you may want to check your air conditioner. Mold can grow inside the air conditioner and blow spores and musty odors around your home. Here are some things that can cause mold in your air conditioner and some ways to fix the problem.

Why Mold Grows in an Air Conditioner

The inside of the air handler is an ideal breeding ground for mold. The space is dark, damp, and has dust that provides a food source. If you change your HVAC filter on a regular schedule, dust in the unit will be much lower than if you get lax or forget to change the filter. If the filter also gets damp, mold can grow on the filter when it's dusty.

Even if the filter stays dry, a dirty filter is a problem since it allows more dust to get sucked inside the air handler to coat the evaporator coil. The evaporator coil is always damp due to condensation, so when the dust settles on the damp coils, mold will grow.

Blocked drain lines can also encourage mold growth in your air handler. Your AC has a pan that collects the condensation water from the evaporator coil. Water from the pain flows out a drain line to empty outdoors or in a floor drain. If the line is clogged, water spills over the pan and in the air handler. This can cause mold to grow on your air conditioner as well as the floor below.

How to Get Rid of Mold in Your AC

An air conditioning service can try a few things to get your AC clean and dry so mold won't be such a problem. This may entail cleaning and sanitizing the evaporator coil to get rid of mold and dust. The service technician may also work on unclogging the drain line so condensation can flow away from the air handler.

If you have allergies to mold or if mold goes away and then comes back, the air conditioning service might recommend installing a UV light in the air handler. The light shines continuously on the evaporator coil so mold is killed and prevented from growing. A UV light can also be installed in the ducts that kills mold spores in the air that circulates through your home.

You may need to control mold and humidity in your house to keep mold out of your AC. If you have mold growing elsewhere, the spores can spread to the air handler and start growing mold if there isn't a UV light installed. Once the service technician cleans, dries, and repairs your AC to get rid of the mold, you'll want to keep your home dry and free of mold so the problem doesn't return. Contact local air conditioning services to learn more.