Though experts say that our recent Central Florida heat waves have kept tropical storms at bay, you may not be feeling grateful for our recent triple-digit temperatures. After a scorching day here in the Palm Harbor area, most of us look forward to relaxing in our air-conditioned homes.

Of course, when your home feels as warm as the air does outside, you might not feel much relief!

If you’re struggling with humid home temperatures and wondering, “Why is my AC blowing warm air?” we’ve got you covered. Here are a few common culprits when it comes to this tricky AC problem.

Thermostat Issues

The first thing to check when your air conditioner is blowing warm air is the thermostat.

If you’re lucky, the issue will be a simple accident with the settings. Check the temperature on your thermostat and make sure it’s set to “cool.” You’ll also want to confirm that your fan setting is “off,” as this keeps your air conditioner from blowing hot air when it isn’t actively cooling your house.

Clogged Air Filter

One of the most common reasons for an AC unit to start blowing hot air is a clogged air filter. Though your air filters might seem like a small component of your AC system, they can affect its performance.

When your air filters are choked with dust, dirt, and airborne pollutants, your system has to work much harder to circulate air throughout your home. Worse, if this problem is left unchecked, it can cause other major AC issues, including some of the ones we’ll discuss below.

Experts recommend that you change your air filters at least once every 30 to 90 days, though the details will depend on your household makeup. If you aren’t sure how often to replace them, try to check them once a month to see how they’re performing over time.

Frozen Evaporator Coils

It sounds a little strange to talk about frozen AC components in the middle of our scorching Florida summers, but an ice buildup on your evaporator coils can do a lot of damage. This can happen as a result of a clogged air filter, which can affect the airflow to your system’s coils.

When your evaporator coils freeze, your AC may start to blow warm air, or it may not circulate air at all.

Though changing your air filter will help with this problem, you will still need to call a local handyman to clean the coils. Don’t try tackling this cleanup job on your own at home!

Clogged Condensate Drain Line

Your condensate line is what allows your air conditioner to send moisture outside your home. This ensures that the humidity from the system’s cooling process doesn’t stay indoors.

However, with moisture comes things like algae, mold, and mildew—all of which can build up in your system. If your condensate line clogs, it can impact your AC’s ability to push moisture out of your home and cause it to blow warm air.

Refrigerant Leak

As the name suggests, refrigerant is what helps your air conditioner cool the air it circulates throughout your home. If your refrigerant starts to leak, it can cause your AC to blow warmer and warmer air over time. You can spot a refrigerant leak by the sound of hissing or bubbling, or you might notice the development of tiny bubbles in your evaporator coils.

It’s worth noting that the fix for this issue isn’t a simple trip to the store for more refrigerant. You’ll need to patch the hole, which is work best left to an expert AC company. Furthermore, refrigerant is a hazardous substance, and you should only handle it if you’re trained in the right safety measures.

Leaking Air Ducts

If the dip in your home’s temperature is a mild one, you might be dealing with ductwork issues instead of an AC system failure. Leaks in your home’s ducts can allow the cool air your AC is blowing to escape through small cracks, mingling with the warm air in the rest of your house. As a result, the air that comes from your AC vents might feel warmer than usual.

Getting regular AC maintenance is a good way to check for duct issues, though you can check with an expert for more extensive cleaning and servicing as needed.

Fan Issues

The fans in your air conditioner help circulate the air through your home, so it shouldn’t be a surprise that fan issues can harm your system overall. When your fans don’t work—due to a failed motor or poor lubrication, for example—your AC may start blowing warm air instead of cold air.

Though fan issues are relatively easy to fix, it’s important to catch them as soon as you can. Running your system with malfunctioning fans can cause your compressor to fail.

Why Is Your AC Blowing Warm Air?

Every air conditioner issue is different, and it can be hard to diagnose the root cause on your own. The list above can help you search for the most likely culprits within your system, but you may need professional AC services to help you find and address more troublesome causes.

That’s where our expert team comes in.

Comfort All-Stars is here to ensure that you can count on your air conditioner during the hottest days of the year and beyond. We serve residential and commercial customers throughout Palm Harbor, Tampa, Oldsmar, Safety Harbor, and Clearwater. If you’re still wondering why your AC is blowing warm air, contact us for AC repairs and more.

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