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What’s that smell?
If it’s a musty, moldy smell, it could be coming from your portable AC.
In this article, I’ll go over the causes of musty smells from a portable air conditioner. I’ll also discuss how to remove musty smells from your portable air conditioner.
Table of Contents
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 produce water by removing moisture from the air.
As the air conditioner cools the 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 your air conditioner is the perfect place for mold, mildew, and bacteria to grow.
But these organic substances need more than water to survive. Dust, dirt, and particles provide food for organic substances in your air conditioner.
As your air conditioner runs, dirt and dust accumulate inside of it. 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
Oftentimes, giving your air conditioner a thorough cleaning will help reduce its musty smells.
However, if you let the mold and bacteria growth get out of control, 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.
Here are the steps that you should take if your portable AC smells musty:
- Clean the air filter
- Clean the evaporator coil
- Clean the condensate tank and drain pan
- Clean the condensate drain line
I’ll go over them below.
Clean the air filter
If your portable air conditioner smells musty, the first thing that you should do is clean its air filter.
The purpose of the air filter is to trap dirt, dust, and other particles before they enter your portable air conditioner.
Portable air conditioners almost always have reusable filters. These filters are cleaned by blowing them with air or rinsing them out with water.
There are usually two air filters in a portable air conditioner:
- Evaporator air filter
- Condenser air filter
Both of these filters need regular cleaning to keep mold and bacteria from growing inside your air conditioner.
The particles on an air filter provide a source of food for mold and bacteria to feed on.
To clean your portable AC’s air filters, follow the steps below:
- Turn your AC’s power off
- Remove the plastic grille that is covering the filter
- Remove the air filter
- Clean the filter out
- Replace the air filter and grille
Turn your AC’s power off
Ensure that the AC is powered completely off before removing the air filters.
Remove the plastic grille that is covering the filter
Sometimes the grille gets a little dusty, so you might want to clean it as well.
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’s a good idea to put the filter in a trash bag so it won’t get your floors dirty while you move through your home.
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 them out with water in your sink.
Ensure the filter is completely clean and dry before placing it back into your air conditioner.
Replace the air filter and grille
After everything is completely dry, reinstall the air filter and grille on the air conditioner.
Clean the evaporator coil
Musty smells can also come from a dirty evaporator coil, so clean your portable AC’s evaporator coil out of its dirty.
The evaporator coil on a portable AC is the part that gets cold and cools down your room’s air.
You can usually access the evaporator coil by removing one of the air filters 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.
My Pick: AC Coil Cleaner
Nu-Calgon Evap Foam No Rinse Evaporator Coil Cleaner
This spray-on coil cleaner helps remove grime build-up from your portable AC coils. Better yet, it doesn't require a rinse after you use it (but I recommend rinsing anyway).
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Clean the condensate tank and drain pan
The condensate tank and drain pan are a haven for mold and bacterial growth.
Follow these steps to clean the condensate tank in your portable AC:
- Turn off your portable AC and unplug it from the power outlet
- Drain the water out of the condensate tank
- Clean the tank or pan with soap and water
- Rinse out the tank with clean water
- Drain out all the remaining water from the tank
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 so unplug it before proceeding.
Drain the water out of the condensate tank
Set a bucket or container under your portable AC’s drain spout and unscrew the cap to let the water out.
Clean the tank or pan with soap and water
Scrub your portable AC’s tank and pan with a non-abrasive scrubber and mild detergent.
Rinse out the tank with clean water
Rinse out your tank and drain pan with water. Make sure you don’t miss cleaning any parts. Any remaining dirty areas will serve as a point where future mold and bacterial growth can restart.
Drain out all the remaining water from the tank
Drain out all the water so you have a clean, empty tank when you’re finished.
Clean the condensate drain line
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.
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.
Follow these steps to clean your portable air conditioner’s drain line:
- Turn off and unplug your portable air conditioner
- Empty the condensate tank and drain pan
- Remove the condensate drain line
- Clean the drain line
- Flush the drain line with a drain pan cleaning solution
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, so unplug it before proceeding.
Empty the condensate tank and drain pan
Empty out the condensate drain tank before cleaning the drain line. You don’t want any water to accidentally drain out of your AC while the drain line is removed.
Remove the condensate drain line
Remove the drain line by slowly pulling it off of the drain spout.
Some drain lines may have a zip tie that needs to be removed.
Clean the drain line
Use water pressure from a faucet or garden hose to dislodge any built-up grime in the line.
Use a hose cleaner tool to scrub out built-up grime on the interior walls of the hose.
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.
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Flush the drain line with a drain pan cleaning solution
Use a drain pan cleaning solution to prevent slime and mold growth in the future.
