It’s scorching outside, so you turn on your air conditioner expecting instant relief.
You wait…place your hand over the vent…and instead of cold air, you feel warm air blowing through your home.

That can’t be right.

Your air conditioner has two key jobs—removing humidity and keeping your home cool. When it blows warm air, something is interfering with that process. Fortunately, the most common causes are simple to fix.

Let’s start troubleshooting.

Check Your Thermostat

“Check your thermostat” is the HVAC version of “Have you tried turning it off and on again?” You’ve probably already looked—but check it one more time.

Make sure:

• The thermostat is set to Cool

• The temperature is set lower than the room temperature

• The Fan setting is on Auto, not On

• The batteries have enough power

If everything looks correct and warm air is still blowing, move to the next step.

Your Evaporator Coils May Be Dirty

Dirty evaporator coils can freeze over and stop absorbing heat from your indoor air. When the coils freeze, your system cannot cool your home.

A common cause of dirty coils is a dirty air filter. Dust and debris from old filters can settle on the coils, blocking airflow and forcing the coil to freeze.

This is one of many reasons to change your air filters regularly.

While it is technically possible to clean the coils yourself, it’s easy to damage them and unsafe without proper training. We recommend professional maintenance.

Your Condenser Coils Could Be Clogged

Your outdoor unit, known as the condenser, also needs clear airflow to function properly. When condenser coils become blocked by dirt, leaves, or debris, the unit cannot release heat—and warm air circulates through your home.

Try this:

• Turn off your AC

• Disconnect power

• Remove visible debris from the outdoor unit

If the coils are heavily clogged, a professional cleaning is best.

You Could Have a Refrigerant Leak

This is the worst case scenario. Refrigerant leaks:

• Prevent your AC from cooling

• Are harmful to your health

• Are dangerous for the environment

• Require a licensed HVAC technician to repair

If you suspect a leak, turn off your system immediately.

Need Fast AC Repair? We Can Help

If your air conditioner is blowing warm air and you need air conditioner repair in San Marcos, TX, call Comfy Air. Whether the problem is a thermostat issue, dirty coils, or a refrigerant leak, we’ll diagnose and fix it quickly.

Don’t tolerate warm air on a hot Texas day—give us a call and we’ll get your AC cooling again.