Here's What to Do If Your AC Has Mold on the Outside

If you've noticed something fuzzy growing on your air conditioner, it's highly likely your AC has mold on the outside. While mold can be a serious concern, something that makes you and your family sick if not taken care of, there's no need to panic. You can take steps to clear away the mold and even keep it from coming back. Learn what you should do if your AC has mold outside of it.

What to Do About Existing Mold

You've spotted mold on your AC. Don't panic. Here's what you can do.

1. Replace the Unit

What you should do if you see mold on the outside of your air conditioner or mold on the windowsill depends largely on the type of AC you have. If you spot mold outside of a window AC unit, it may be time to replace it, especially if there are significant amounts of mold growing in or on it. 

If you have central air conditioning or an HVAC unit or notice mold in your furnace, too, replacement may also be your best option, depending on the extent of the mold issue. Once you replace the moldy AC, you can take steps to minimize or prevent future mold growth.  

2. Clean and Disinfect the Unit

You may be able to clean away a light coating of mold on the outside of your AC, as long as the mold hasn't gotten into the ducts or isn't growing in the evaporator coil. If you don't notice a mold smell in your house when you run the AC, similar to a musty odor, it's highly likely that the mold growth is limited to the exterior. 

To clean your AC, you'll need two things: the right protective gear and a product that will kill the mold. For protective gear, wear a mask, gloves, and safety goggles. As for a cleaning product, a mixture of one part bleach to 10 parts water would work. Another option is to use one part distilled white vinegar and one part water.

3. Call in a Professional

If you're concerned about mold that has spread throughout your AC or HVAC system or you want to know how to get rid of black mold, your best bet is to bring in a professional to investigate the issue and give you advice on controlling the mold growth. 

You may need to spring for a professional cleaning and mold remediation, which costs between $3,000 and $10,000 for an entire HVAC system.   

If you end up replacing your AC entirely, it may be worthwhile to work with a professional HVAC company near you and have them perform regular inspections and cleanings of your unit, to keep mold at bay.

How to Prevent Mold on Your AC

You've cleaned your AC or had a new one installed. Here's how to keep mold growth to a minimum.

1. Monitor Indoor Humidity

Remember, mold loves moisture. One way to keep it from thriving is to keep the humidity levels in your home within the recommended range of between 30% and 50%. Installing or running a dehumidifier is one way to lower the humidity in your home. 

Other ways to reduce indoor humidity include: 

• Opening the windows or running a fan while you shower

• Ensuring your attic is properly ventilated

• Checking for and sealing up air leaks

2. Change Your AC's Air Filter

Your air conditioner's air filter keeps dust and debris from getting into the system and clogging it up. But it can only do so much. Once the filter gets full, it doesn't do as good a job keeping mold away. In fact, a dirty or clogged air filter can actually provide an inviting environment for mold growth.

Your best bet is to swap out or clean the air filter regularly. During the summer, when your AC is working overtime, that may mean changing the filter every month or so.