What to Do When Your AC Turns On But Doesn’t Cool

You hear the familiar hum of your air conditioner kicking on. The fan’s running, and everything seems normal—until you realize something’s off. The air blowing through your vents is warm, and your home isn’t getting any cooler. If your AC turns on but doesn’t cool, don’t panic—this is a common issue, especially during the blazing summers here in the Dallas-Fort Worth Metroplex.

At Texas Air Authorities, we’ve helped countless homeowners troubleshoot this exact problem. Whether it’s something simple or a more serious issue, knowing what to look for can save you time, money, and stress.

1. Check the Thermostat First

It may sound obvious, but always start with the thermostat. Make sure it’s set to “cool” and that the temperature is lower than the current room temperature. If it’s set correctly but still not cooling, try replacing the batteries or resetting the thermostat.

Smart thermostat users: Make sure your system isn’t in an energy-saving mode that limits cooling or temporarily raises the temperature.

2. Inspect the Air Filter

A dirty or clogged air filter can block airflow and prevent your system from cooling effectively. When air can’t flow properly, it can cause your system to overheat, freeze up, or simply push warm air through the vents.

Quick fix: Replace your air filter if it looks dusty or hasn’t been changed in 1-2 months. This is one of the easiest ways to improve your AC’s performance.

3. Check the Outdoor Unit

Your AC’s outdoor unit (the condenser) plays a key role in cooling your home. If it’s covered in debris, leaves, or dirt, it may struggle to expel heat, which can result in warm air indoors.

Pro tip: Make sure the outdoor unit is clear of obstructions and the fan is spinning. If it’s humming or buzzing but not running, the problem could be a bad capacitor or electrical issue—something our NATE-certified technicians can diagnose quickly.

4. Look for Ice on the Evaporator Coil

If your indoor coil (usually located inside the air handler or near your furnace) is frozen over, that’s a red flag. It means your system isn’t getting enough airflow or there’s a refrigerant issue.

Turn the system off and set the fan to “on” (not “auto”) to help thaw the coil. Then call us for an inspection. Operating your AC with a frozen coil can cause serious damage to the compressor.

5. Low or Leaking Refrigerant

If your system is low on refrigerant, it won’t be able to absorb and release heat properly—which means your home stays warm even if the AC runs non-stop. Low refrigerant is often caused by a leak, and adding more without fixing the leak is just a temporary bandage.

Our skilled team can locate and repair refrigerant leaks and recharge your system to manufacturer specifications.

6. Compressor Problems

If your system is running but not cooling, and you’ve ruled out airflow issues, the compressor could be the culprit. This component is the heart of your AC, responsible for circulating refrigerant. When it fails, your system might blow air—but it won’t be cool.

Compressor failure is serious but not always irreversible. Our team will evaluate whether a repair or replacement is the best long-term solution.

Conclusion

Trying to troubleshoot your AC on your own can be frustrating, especially when it’s 100 degrees outside. That’s why Texas Air Authorities offer same-day appointments, free estimates, and expert diagnosis across Arlington, Fort Worth, and surrounding cities.

Whether it’s a simple filter change, a refrigerant recharge, or a full system issue, our team of experienced, NATE-certified technicians will get to the bottom of the problem—fast. We stand behind every job with a 1-year warranty on all new equipment and repairs, and we treat your home with the respect it deserves.

Call Texas Air Authorities today, and let’s get your cool air flowing again—before Texas heat gets the best of you.