turn on AC

Why am I smelling mildew when I turn on my AC in the Spring?

The air conditioner is one of the devices that we use the most. It keeps up cold in the summer, and it can keep us warm enough in the winter. It is said that in most households, people use the AC in the warm months, and they usually choose another device for heating in the winter. So, every year, when we turn our air conditioner on after at least 6 long months, we expect to experience that feeling of dust that goes away after a few seconds.

However, some homeowners have reported that when they turn the device on in the warm months, they can feel that wet smell and it seems like there is something wrong. If you are one of those people, and if you’ve experienced the moldy smell when you turned your device on, you’ve come to the right place. In this article, we are going to give you more information on why you may be smelling mildew when you turn your AC on in the spring, and what you can do about it.


What is the cause of the problem?

Let’s first talk about the cause of this issue, and what are the possible reasons for you to experience a musty smell coming out of your AC. Experts and users say that there are several main reasons why this may be happening, and it would be best if you go through all of them until you find the main cause.

The most common cause of this may be leaking in the air ducts. You can notice this is the air conditioner is on all the time, but your home seems to be warm. Another sign is if you can smell dust as well, and it is like there is no filter in the AC. Humidity can be also a sign, and if you notice that the air is constantly humid, and if there seem to be condensation, or drops of water on the windows, this may be a sign that the air ducts are leaking.

Know that the problem usually occurs from leaky ductwork under the home that draws the moldy air into the home when the air conditioner gets turned on. In case there is a crawlspace in your house, and if it is not encapsulated, chances are, there is mold growing there, and the ducts of your AC are drawing that air, and smell with it.

Another common cause of this problem is clogged drain. The easiest way to notice this is if you can see a pool of water forming around and inside the unit. This means that the duct is clogged, and the water has no way of leaving the device. You may not notice this at first, but you will definitely smell the moisture.

The last cause we are going to talk about is a dirty evaporating coil. Know that this is not something that you can foresee, and it is bound to happen at one point or another. The problem with this is that a dirty coil is going to present a perfect ground for mold to grow, and this will lead to the mildew smell. Dust will start gathering in the opening, and when combined with humidity and warm air, it is going to provide the perfect space for bacteria, mold, and sometimes even insects and pests.

control inside air


Now let’s talk about the solutions to these common problems. If you are experiencing leaking air ducts, then the easiest way to fix this is to clean the duct. After cleaning it you will be able to see where the leaks are, and access if you need to replace them or fix them. If you choose to fix it, then you should be able to do it with flex tape, or duct sealing solution.

You may also be experiencing the mildew smell because of the mold in your crawlspace, so the easiest way to fix that is to first clean your crawlspace, make sure you get rid of all the mold, and then fix the ductwork, and encapsulate it to prevent further deterioration. By encapsulating your crawlspace you will not only prevent any musty smell in your home, but you will also protect it from mold, insects, pests, and damage to your wooden areas.

In case the drain of the air conditioner is clogged, then you can easily fix this on your own. The only thing you need to do is take it out and clean it. See what clogged it, if there is any debris left, and use a stream of water or plumber’s snake to remove the clogging. Note that you should never use too much force because you may end up damaging the drain.

Finally, the solution for a dirty evaporating coil is to contact HVAC professionals. Even though you may be able to clean this part on your own, you risk damaging the unit and fixing it will cost a lot more than a simple service.

How to prevent it?

Now let’s talk about prevention and what you can do to make sure this does not happen to you. Well, the first thing you need to do is make sure your home is mold-free. You can start by encapsulating your crawlspace, and cleaning your pipes and drains.

When it comes to the AC unit itself, you need to clean and maintain it regularly. No matter how good you think it is working, you should not wait for a problem to occur to start paying attention to the details. Check it regularly, especially in the months when you are using it. If you notice any blockages, clogged drains, or ducts, you need to turn it off and clean it completely. Don’t forget to inspect it after the warm months, so there won’t be any leftover condensation or water.

Know that for all of these things, you can contact a professional service that will help you maintain your air conditioner, along with the rest of your home. Don’t wait until it’s too late, and don’t risk your health and your family’s well-being. When you properly maintain your units, you will prolong their lifetimes, and you will make sure they are going to serve you for many years to come.