4 Reasons Why Your Air Conditioner Smells Musty (and What to Do About It!)

What does it mean when your air conditioner smells musty?

Air conditioner odors are no joke, especially if you live in a warm climate like Forney, Texas. It’s important to keep yourself and your family cool during the summer, but when your AC smells, cooling the house can be quite unpleasant. There are several types of air conditioner smells that homeowners can experience, but a musty air conditioner is perhaps the most common.

If you’ve been wondering, “Why does my AC smell musty?” then you’ve come to the right place. This article will explain four possible reasons that your air conditioner is smelling musty. We’ll also go into detail explaining what you can do to get rid of a musty air conditioner smell.

No one should have to deal with unpleasant odors just to keep cool. Whether you live in the Dallas area or somewhere else entirely, keep reading to find out what causes a musty air conditioner and what can be done about it.

1. The Drain Pan Is Full: An air conditioner doesn’t simply pump cool air into your home. Your AC unit also removes humid air from inside your home, which means it collects water, too. As it draws humid air in, water droplets from the air are collected in the drain pan (or drip pan).
   Like every other component on your air conditioner, the drain pan is susceptible to normal wear and tear, and its functionality will deteriorate with time. If the drain pan becomes full of water, it can start to accumulate mold. This is what causes that musty smell when the drain pan is full.
   You can find the drain pan yourself by looking for it in a compartment under your AC’s evaporator coils. If there’s mold or standing water in the drain pan, a qualified HVAC technician will need to replace it for you. This should eliminate the musty odor in your home.
2. There’s Excess Moisture In The Ducts Or Vents: When it comes to home maintenance, few things are more important than avoiding moisture damage. Moisture damage is usually caused by things like roof and plumbing leaks, but excess moisture buildup can occur anywhere in the home. If it builds up inside your home’s ductwork, it can cause a musty smell to permeate your entire house.
   When moisture accumulates inside vents and air ducts, it’s usually a result of high humidity levels or drainage leaks. If you notice a musty smell as soon as you turn on your AC, there’s a strong chance that mold or mildew is growing in your ductwork.
   Mold exposure can cause serious respiratory health issues, so it’s not something to be taken lightly. If there’s mold or mildew in your ductwork, it will need to be thoroughly cleaned and repaired to remove musty smells for good.
   You may be able to see mold or mildew buildup if you look inside the vents in your home. If your ductwork is mostly contained in the ceiling or crawl space, a technician will need to inspect it to find out if your mold issue is extensive.
3. The Evaporator Coils Are Frozen: The way an air conditioner works is by absorbing warm air from inside the home, removing the humidity from it and cooling it, and then cycling it back into the house through return vents. As you can imagine, unobstructed airflow is critical for the system to work properly. If airflow gets blocked, such as by dirty air filters, it can cause moisture problems.
   When dirt and debris block airflow, water droplets from the humid air is allowed to build upon the AC’s evaporator coils. As the AC unit cools the air with refrigerant, the droplets on the coils can freeze. This can result in an unpleasant musty smell.
   You can look inside or near the air handler, where the blower fan is located, to see if your evaporator coils are frozen. If they are, you’ll need to let the coils thaw and change all the air filters to provide maximum airflow in the future.
4. You Have The Wrong AC Size For Your Home: In order for your HVAC system to work properly, it needs to be the right size for your home. If your air conditioner is too large, it will cycle air through the house too quickly, resulting in a lack of dehumidification and excess moisture. If it’s too small, it may be forced to run too frequently, causing excessive wear and tear.
   Having an AC system that isn’t the right size for your home can result in moisture problems, leading to that musty smell. A technician can tell you whether you have the right air conditioner for your home or you need a different one. Besides getting rid of mustiness, getting the right size of air conditioner may help make your home more energy-efficient.