There's nothing worse than sliding behind the wheel on a sweltering summer day and being greeted with a blast of hot air. If you find yourself asking the question, "Why is my car AC blowing hot air?" again and again, it may be time to take a deeper look into why you're having this issue. While there are many variables that factor into your car AC blowing hot air when it shouldn't, we took the time to highlight a few of the biggest reasons why this happens as well as how you can fix them.
Your car's electrical system is a net of wires that can be difficult to pick apart for the untrained eye. If a single one is frayed, burnt or damaged, it can signal a snowball effect that could be the cause of your car AC blowing hot air. Your car is designed to shut off certain functions to avoid accidents or fires due to faulty wiring. Something simple like a blown fuse can cause your AC to shut off, so it's important to have a full diagnostic test run on your car by a professional.
Not Enough Refrigerant/Freon
It could be that the liquid responsible for that nice, cool breeze that you feel in your car is either low or leaking. Refrigerant (also referred to by its brand name "Freon") is a tricky substance because it is a liquid when compressed, but a gas when it comes into contact with air. If there's a leak, it may be a tough job to spot it with the naked eye. Sometimes a strange odor or poor airflow from your vents can tip you off as a driver. You may find an oil residue around your AC pipe fittings and hoses. If you suspect a refrigerant leak, or simply need to top off your refrigerant levels, you can make an appointment with your local Tire Outlet specialists to get the job done.
The condenser is an essential component of your car's AC system, and if it's blocked by dirt or debris, it could result in your AC blowing warm air from your dash. Essentially, the main job of the condenser is to cool off the gaseous refrigerant as it's working, thereby converting it back into a liquid form. The liquid Freon then turns back into a gas and reenters the same cycle, cooling the air in your car and continuing the process. Without the condenser firing, chances are you'll sweat this summer.
The compressor is the most important part of your AC system, seeing as it is the piece that is constantly moving in order to keep refrigerant flowing through your vehicle. If the compressor is not working properly, then you're not getting a free flow of Freon, and you will never be able to get cool air to blow in your car's cabin. The compressor needs to be engaged in order to keep working smoothly, and the biggest cause of compressor issues is inactivity. So, in the winter when your AC is off, try running cold air through your car for fifteen minutes or so after work before you head in for the night; your future summer self will thank you.
Damaged Cooling Fans
The cooling fans work with the compressor to cool the air in your car – but they are fragile. Check to make sure they are not cracked, chipped or damaged due to debris, and check that they are running at the correct speed. Make sure nothing is jammed between the blades, like leaves or bugs, and that the space is clear enough for the blades to move. If your cooling fans aren't operating properly, it could result in your car AC not blowing cold air.
Your Filter is Dirty
In order to get the most out of your car's AC, you're going to want to check your filters regularly to make sure they're clean. According to Consumer Reports, "a dirty filter prevents optimal airflow," so you're going to want to make sure that you don't see a lot of dirt or debris accumulated on yours. Besides the fact that it can lead to your AC blowing warm air, car issues aside, a dirty filter is often full of dust and germs that you and your passengers are breathing in as you drive.
Your Blend-Air Door is Stuck
Starting your car requires warm air to flow over your engine and into your car; this is something that the blend door (aka "air mix door") helps to fight against. When the blend door flips over your ventilation system, it stops this warm air from entering the cabin and allows your AC to pump in the cool air you need. If your blend door is stuck, no amount of cool air will ever get through; you'll just get warmer and warmer.
Before you hit the road this summer, make sure you check off the list above if you feel a little sweaty in your front seat. Stop by to see one of our professionals at the Tire Outlet closest to you so we can take an in-depth look at your car's AC system for you.