Why Does My Air Conditioner Smell Like Mildew?

A malfunctioning air conditioner is a problem no homeowner wants to deal with, and for good reason. AC repairs are a nuisance. From scheduling a service call from your local HVAC contractor to possibly taking time off work for the appointment, paying for the unexpected repair costs, or worse, needing a complete air conditioner replacement.

But what happens when your air conditioner starts smelling funky? In particular, why does your air conditioner smell like mildew? If you need expert AC services, call us today or contact us online.

4 Reasons Your Air Conditioner Smells Like Mildew

Your air conditioner may smell like mildew because:

1.) Your air conditioner has a clogged drain pan: Your air conditioner’s drain pan prevents condensation buildup in your cooling unit or worse, in your home. It’s a sloped pan and pipe that transports the collected condensation either outside or into your home’s plumbing system.

If your air conditioner drain pan is clogged, the water can’t drain and may cause mildew to build up in your unit and make your AC smell like mildew.

2.) Your air conditioner has a clogged drain pipe: Similar to the clogged drain pan, a clogged drain pipe may also cause water to collect inside your air conditioning unit and result in a mildew smell.

3.) Your ductwork collects condensation or is moist: If your home’s ductwork isn’t sealed properly, excess moisture can collect in your ducts and lead to mold and mildew growth. Over time, this buildup lives in your ductwork and any air passing through may pick it up and disperse it through your home, causing a mildew smell from the AC vents.

4.) Your air filters are dirty or clogged: If your air conditioner’s air filter is dirty, clogged, or too exposed to moisture, mildew may begin to grow. If your air conditioner smells like mildew, you should check your air filters for mold or mildew growth.

What To Do if Your AC Smells Like Mildew

If your air conditioner smells like mildew, you can get rid of the smell pretty easily. Locate your AC’s drain pan and unclog it (if it’s clogged). Remove the clog and add a small amount of bleach to the pan to kill the mold or mildew.

We recommend a ratio of one cap of bleach to every one gallon of water.

You can also clean the evaporator coils with your water/bleach mix. Leave the bleach and water solution on the coils and in the drain pain for at least 10 minutes to kill all the mold and mildew.

Still Smelling Mildew From Your Air Conditioner?

If you can’t get rid of the mildew smell from your air conditioner, call a heating and cooling company for air conditioner repair.

If you live in St. Louis County, Missouri, and your air conditioner smells like mildew, give us a call. Our cooling specialists can diagnose and repair your air conditioner as soon as possible.