After a day out in the blistering hot sun, the first thing you probably want to do is hear the sweet click of your air conditioner. You wait for the cool breeze to whisk you away, drying your sweat in a chilly instant. But the reality is never quite like your expectations.

Instead of being met with refreshing air, you get slapped in the face with a horrifying stench. A smell that reminds you of high school locker rooms and stinky socks.
Why does this happen? And why does your AC smell musty all of a sudden?

Don’t worry, though, because, in this blog, we’ll cover all the possible causes of that foul stench coming from your air conditioner.

Why Does My AC Smell Musty?

If you live in a humid environment, dealing with an air conditioner that smells musty is probably a common occurrence. So much so that there’s even a name for it!

Dirty Sock Syndrome is when your AC starts to throw out air that smells damp and dusty. This happens because mold and mildew are quick to take root in humid weather conditions, which further causes stinky airflow.

During this, the bacteria in the mold grows and takes root in the AC’s evaporator coil. So if you smell something stale, or a weird, damp scent wafting from the grills of your AC, there’s a high chance mold has settled on the inside.

Common Causes of Musty AC

It’s true that mildew accumulating on the internal parts of your air conditioner can lead to an unsettling smell. But how exactly does it happen in the first place, and what parts of the AC should you keep an eye on? Well, we’ve got you covered. Below are some typical reasons why your ac blasts out musty air.

The Drain Pan is at its Limits

When your AC’s drain pipe is full, it can cause severe issues such as flooding, leakage, and, worst of all, mold growth. To prevent this, regularly check your drain pan when needed.

Frozen Evaporator Coils

If your ac filters aren’t clean, the dirt on them can obstruct the airflow. This can lead to water droplets forming and freezing on top of the evaporator coils.

Vents Filled With Excess Moisture

Due to high humidity, or in some cases, internal leaking, moisture can get trapped inside the ac vents and cause mildew to grow.

Blockage in the Condensate Drain

The condensate drainage line is a PVC pipe that runs from your ac to its central unit outside your house. When the water in the pipe isn’t properly drained, it can become a hub for bacteria to fester and spread.

Unclean Filters

Dirty ac filters are probably one of the easiest problems to fix. Not to mention, they’re also the fastest way to allow mold and mildew to sprout inside your ac. Thus, to prevent the musty smell, try to clean your ac filters regularly.

Wrong AC Size

An ac unit that is far too huge or too small can cause problems. For instance, if the unit is too big, it could cycle through fresh air too fast without properly dehumidifying. Whereas a small ac unit would continuously trip, leading to moisture buildup.

Leaking Air Ducts

When the air ducts connected to the ac get ruptured or develop holes, they’re bound to leak. The moisture inside the ducts can then get compromised, leading to mold accumulation.

How Do I Fix It?

Now that you know all about the root cause behind why your ac smells musty, you’re probably wondering how to fix it. The first thing you can do is clean the filters, just in case. But to make sure your air conditioner keeps running for a long time, routine maintenance is key. Contact Crump AC & Heating for the best AC touch-ups at (281) 533-9200.

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