If you feel AC blowing hot air from your vents when the AC is running, you likely have one of the following problems:
- Thermostat is Set Incorrectly
- AC’s Refrigerant Levels are Low
- AC Compressor Pump is Faulty
- Outside Condenser Fan Isn’t Working
- Dirty, Clogged System
- Frozen Evaporator Coils
- Duct Leaks
Continuing to run your HVAC system when there is an existing issue can cause greater failure to your equipment. To help you navigate your AC blowing hot air, we’ll split up the list above into problems you can solve and problems you’ll need a professional to solve.
Need an AC repair right away? Contact our team and we’ll send out a technician as soon as possible to get your cool air restored quickly.
Thermostat Is Set Incorrectly
- It’s set to HEAT, not COOL. This might sound silly, but you’d be surprised by how many times this simple mistake has prompted an unnecessary service call.
- The fan is set to ON, not AUTO. Make sure that your thermostat fan setting is set to “AUTO,” not “ON.” Leaving it set to “ON” will cause the indoor fan to run 24/7—even when the AC isn’t in cooling mode. This can cause homeowners to mistakenly think the air conditioner is blowing warm air, when the fan is simply circulating indoor air.
- The thermostat is not set below the room’s current temperature. If the desired cooling temperature is not set at least 2 degrees (or more depending on how the thermostat was set up) below the current temperature shown on the display screen, it will not communicate with the system to activate cooling mode.
- Your thermostat’s batteries need to be replaced. Most battery-operated thermostats have a “low battery” indicator to see if they need to be replaced. If the batteries are dead, your thermostat cannot communicate with your HVAC system.
2. AC’s Refrigerant Levels are Low
If your AC is blowing hot air, it might be due to low refrigerant levels. Refrigerant isn’t used up in an AC system, so a leak is usually the culprit. A professional will need to locate the leak, repair it, and then recharge the system to restore proper cooling. Without the right amount of refrigerant, your AC's compressor will not keep cool. If your compressor cannot stay cool, your AC can't cool your home effectively, which can cause long-term damage if not addressed.
3. AC Compressor Pump is Faulty
The compressor pump is like the heart of your AC system—it's responsible for circulating refrigerant throughout the system to keep things cool. If the motor in the compressor pump malfunctions or fails, the refrigerant won’t flow as it should, preventing your AC from properly cooling your home. A faulty compressor is a serious issue that needs attention, as it impacts the core function of your AC system and could be the reason behind your air conditioner blowing warm air. A professional technician will need to diagnose the issue, replace the pump if necessary, and ensure everything runs smoothly again.
4. Outside Condenser Fan Isn’t Working
The condenser fan is responsible for moving heat from your home to the outside air. If the fan isn’t working, the refrigerant cannot do its job, and heat can’t escape from the AC system. A professional technician can check and repair the fan to make sure it’s working properly, allowing the system to release heat efficiently.
5. Dirty, Clogged System
Changing your HVAC filters regularly and keeping your system's components clean is the easiest way to keep the air flowing in your home. Dirty and clogged filters can cause major problems by restricting airflow and preventing your AC from pulling in enough air to cool your home efficiently. The same goes for indoor and outdoor coils, as well as fan blades—they all need to be kept clean to run efficiently. Clean components not only improve performance but also help your system last longer and can even lower your energy bills.
6. Frozen Evaporator Coils
Restricted airflow or low refrigerant can cause moisture to freeze on the evaporator coils. When these coils freeze, airflow is blocked and the system cannot function properly, leading to warm air blowing through your vents. A technician will need to thaw the coils and address the root cause of the issue to prevent future freezing. This is another potential reason for your AC blowing hot air.
7. Duct Leaks
Leaks in the ductwork can allow warm air from other areas of your home to mix with the cooled air. This causes the air coming through your vents to feel warm, even when your AC is running. If you’ve been asking, “why is my AC blowing hot air?” Leaks in the supply duct could actually be causing this issue. A professional will inspect and seal any leaks in the ducts to prevent this and ensure that the cooled air stays where it’s supposed to be.
Need a professional AC repair? Trust the pros at Burgeson’s
We’ve had over 76 years of experience repairing AC systems in Redlands and Inland Empire areas. When you choose Burgeson’s for your AC repair, rest easy knowing that you’re getting the highest-quality repair possible and a technician who is trained to put your comfort and budget first.
If you’re ready to schedule your AC repair, contact us today!
