How to Remove Musty Smells From Your Portable Air Conditioner

HVAC Training Shop is reader-supported. As an Amazon Associate, I earn from qualifying purchases.

Your portable air conditioner is an important tool to keep your house cool during the hot months. But with its constant use, your portable AC can start to emit musty smells as it conditions your home’s air.

In this article, we’ll look at the causes of musty smells in a portable air conditioner. I’ll also discuss how to remove musty smells from your portable air conditioner.

What causes musty smells from a portable air conditioner?

Musty smells from a portable air conditioner are almost always caused by the growth of mold, mildew, or bacteria.

So how do these things start growing in your air conditioner?

Air conditioners create water by removing moisture from the air. This moisture is from condensation that forms on the evaporator coil. As the air conditioner cools air, condensation forms on the evaporator coil and then drips off into a collection tank. 

Water collected inside your air conditioner creates a humid, moist environment. The moist environment inside of your air conditioner is the perfect place for mold, mildew, and bacteria to grow.

But these organic substances cannot survive from only water. Dust, dirt, and particles provide food for organic growth inside your air conditioner.

As your air conditioner runs, dirt and dust accumulate inside of it. These particles come from the air stream that flows through the unit. Mold, mildew, and bacteria grow by consuming these particles within your air conditioner’s moist environment.

What to do when your portable air conditioner smells musty

Now that you understand what causes bacteria and mold growth in your portable air conditioner, let’s look at a few ways to get rid of it.

Oftentimes, giving your air conditioner a thorough cleaning will help reduce the musty smells. However, if you allow excessive mold or bacteria growth inside your air conditioner, it will be very difficult to completely get rid of the smell.

Excessive organic buildup inside your air conditioner will cause the smells to become deep-rooted in the parts of the AC.

How do you prevent this?

Always perform regular maintenance on your portable AC to never let it get to that point in the first place.

Below, I’ll go over a few things that you can do to prevent mold, mildew, and bacterial growth.

Clean the air filter

By far, the easiest maintenance that you can do on your portable air conditioner is to clean its air filter.

Portable air conditioners almost always have reusable filters. These filters are cleaned by blowing out with air or rinsing out with water.

The purpose of the air filter is to trap dirt, dust, and other particles before they enter your portable air conditioner.

There are usually two air filters on a portable air conditioner: one for the evaporator and one for the condenser. Both of these filters need regular cleaning to keep mold and bacteria from growing inside your air conditioner.

Mold and bacteria can grow on a dirty air filter. The collected particles on an air filter provide a source of food for these substances to feed on.

To clean the air filters, follow the steps below:

  1. Power your AC off. Ensure that the AC is powered completely off before removing the air filter.

  2. Remove the plastic grille that is covering the filter. Sometimes the grille gets a little dusty so clean it if needed.

  3. Remove the air filter. Be careful to ensure that any caked-on dust or debris does not fall off the filter to the floor of your home. It is a good idea to put the filter in a trash bag so it won’t get your floors dirty while you move it across your house.
  1. Clean the filter out. If the filter is lightly soiled, then you can dust it off to remove most of the debris.

    For air filters that are really dirty or have caked-on debris, then you will need to rinse it out with water in your sink. Ensure the filter is completely clean and dry before placing it back into your air conditioner.

  2. Replace the air filter and grille. After everything is completely dry, reinstall the air filter and grille on the air conditioner.
Filter on a portable air conditioner
A dirty air filter on a portable air conditioner

Clean the evaporator coil

Musty smells can also come from a dirty evaporator coil. 

The evaporator coil on a portable AC is the part that gets cold and cools down your room’s air. The evaporator coil is also responsible for dehumidification as warm, moist air passes through it.

You can usually access the evaporator coil by removing the filter from the back of your portable AC. Use a flashlight to inspect the evaporator coil for any debris such as dirt or hair.

Use a vacuum to suck out any debris from the surface of the evaporator coil.

If there is deep-rooted grime in your evaporator coil, a simple vacuum won’t do the trick. Instead, use a spray-on coil cleaner solution to deep clean your evaporator coil. 

Best for Most Coils
Nu-Calgon Evap Foam No Rinse Evaporator Coil Cleaner

This spray-on coil cleaner helps remove grime build-up from your dehumidifier coils. Better yet, it doesn't require a rinse after you use it.

Check Price
HVAC Training Shop is reader-supported. I earn from qualifying purchases.

Clean the condensate tank or drain pan

The condensate tank or condensate drain pan can be a haven for mold and bacterial growth. 

To clean the condensate tank in your portable AC follow these steps:

  1. Turn off your portable AC and unplug it from the power outlet. You don’t want your AC to power on while you’re cleaning it.

  2. Drain the water out of the condensate tank. Ensure all the water is completely removed from the condensate tank before proceeding

  3. Clean the tank or pan with soap and water. Scrub it out until it’s clean and free of slime.

  4. Rinse out the tank with clean water. Ensure that you didn’t miss cleaning any parts. Any remaining dirty areas will serve as a point where future growth can restart.

  5. Drain out all the remaining water from the tank. You’ll want to have a clean, empty tank when you’re finished.

Clean the condensate drain line

The condensate drain line carries away moisture from your portable AC. Since it comes into contact with lots of water, the drain line is prone to algae and mold growth.

Cleaning the drain line is one of the most important maintenance tasks that you can perform on your portable AC. It is very important, especially if your portable air conditioner is leaking.

To clean your portable air conditioner’s drain line follow these steps:

  1. Turn off and unplug your portable air conditioner. You don’t want your air conditioner to turn on while you are cleaning the drain line.

  2. Empty the condensate tank or drain pan. Be sure the condensate tank is empty before cleaning the drain line. You don’t want any water to accidentally drain out of your AC while the drain line is removed.

  3. Remove the condensate drain line. The drain line can usually be removed by slowly pulling it off of the drain spout. In some cases, there may be a zip tie that needs to be removed.

  4. Clean the drain line. Use water pressure from a faucet or garden hose to dislodge any built-up grime in the line. If you have built-up grime on the interior walls of the hose, use a hose cleaner tool to scrub it out.

  5. Flush the drain line with drain pan cleaning solution. Using a drain pan cleaning solution helps to prevent slime and mold growth in the future.
My Pick: Drain Line Brush
67-Inch Flexible Nylon Drain Brush

This nylon brush is perfect for scrubbing out the interior of condensate drain line tubing for portable ACs.

Check Price
HVAC Training Shop is reader-supported. I earn from qualifying purchases.

Leave a Comment