Ah, the smell of musty air! It’s definitely not a pleasant one, especially when it comes to air conditioners. We’ve all been there: the air conditioner is running, but instead of that cool, refreshing breeze, it’s giving off a musty smell. So, what do you do when the air conditioner smells musty? The good news is: it’s usually something that can be fixed relatively easily. In this article, we’ll cover the most common causes of musty smells from air conditioners and how to address them.
What causes musty smells from air conditioners?
There are a few different reasons why an air conditioner might be giving off a musty smell, but the main culprit are:
The air filter is dirty.
If you don’t clean or replace your air filter regularly, it will build up with dust, pollen, and other particles. This will reduce the effectiveness of your AC by reducing the airflow to the coils and causing it to overheat. This can result in a musty smell. Plus, those particles can get released back into the air when the AC is on, which isn’t good for your health.
The coils are dirty.
The coils transfer the heat from inside your home to the outside through the use of air. When they get dirty, they don’t operate as efficiently, so they’ll work harder and use more energy. This can also result in a musty smell.
The drain pan is dirty and/or the drain line clogged.
The drain pan is what collects any water that comes out of the air conditioner’s coils. If it isn’t cleaned regularly, it can build up with bacteria and mold, which can cause a musty smell.
How to address musty smells from air conditioners
The following are a few measures to help against the musty smell from your AC.
We usually recommend leaving AC maintenance to the experts. However, if you do decide on the DIY approach, make sure to take all necessary precautions for health and safety:
- Disconnect the AC unit from the power
- Wear protective gloves and goggles
Clean or replace the air filter
This is the easiest and most effective way to reduce the chance of musty smells from your AC. Cleaning the filter once a month will greatly reduce the number of particles in the air and keep your AC running efficiently. And if you have a HEPA filter, it will also help to reduce allergens in the air. If you’ve cleaned the air filter and checked the coils, but you’re still experiencing musty smells from your AC, you may want to replace the air filter. The exact cutoff for needing to replace the filter will vary based on the brand and model of air conditioner you have, but as a general rule, a filter should be replaced once every 12 months.
Clean the coils
This should be done in combination with cleaning the air filter. Depending on the coils and the amount of dirt involved, there are various methods of cleaning them: a cleaning brush, compressed air, or a combination of a household detergent or professional chemical with low-pressure water. While it is possible to do this yourself, we recommend having this done by a professional. They will know which method works best in the individual case.
Check the ducts/vents
If you notice a musty smell in just one room, it may be that the ductwork in that room is dirty. You can usually clean the ducts yourself, but again, they are best left to a professional.
Unclog the drain line and clean the drain pan
Normally the AC drain line should carry the water away from the drain pan. Standing water in the drain pan can therefore be a sign that the drain line is clogged. As long as the clog is only small, you might be able to take care of it yourself with the help of diluted vinegar or bleach. Important: You must never mix bleach and vinegar since that leads to the development of toxic gas!
Professional help: The experts from Action Air Conditioning
If you prefer to play it safe from the start or the above methods don’t work, contact the professionals. If your Air Conditioner smells musty, we can also help you to determine if the problem is just due to a small issue like a dirty filter and coils or if it’s something more serious.