What’s Wrong with My AC in My Car?

car ac knob

What does it mean when your car AC blows hot air?

It is only June, but the heatwave of 2021 has started, and now is not the time for anyone’s car air conditioner to quit working!  But then, if it is, getting it to a car ac repair shop now should be a priority, be cause the heat is only going to get worse car ac repair and service shops are just going to get busier. 

The air conditioner in your car is a complex system and if it isn’t blowing cold air, it could be one of these four reasons: 


A car air conditioner needs refrigerant just like the A/C in your home, and if it low or out, then it is going to blow hot air. That refrigerant is like the refrigerant in your HVAC system a liquid that circulates through the A/C system. It contracts and expands as it removes the heat and humidity from inside your car. Without that refrigerant, the other A/C components aren’t able to function.

Why is it leaking? It could be an old hose, a punctured or rusted evaporator. When A/C refrigerant leaks, it doesn’t leave a puddle under your car like an oil leak. The refrigerant, also referred to as freon, evaporates when it is exposed to the air. 

You’ll need a professional car ac repair technician to inspect the system to determine if this is the problem. They do this by injecting a dye into the A/C system which will show them if there is a leak and where, then they are able to repair and recharge the system. 


When a car’s A/C system pulls that heat and humidity out of the car, that refrigerant we mentioned absorbs them. Then, the condenser keeps that refrigerant cool to continue the cooling cycle you know as cold air blowing from the vents. When the condenser isn’t working right, the whole cooling process quits. 

The condenser is located under the hood at the front of your car, usually between the grill and the radiator. The air that flows through the grill help with the cooling and if the condenser has anything blocking it or it becomes clogged, the air can’t the refrigerant cool.

If you have had a fender bender where the grill has been bumped or smashed, the condenser may be broken. Take your car to a car ac repair shop and they can confirm it is the condenser, and install a new one, recharge the system and get your car cooling again. 


The heart of any air conditioning system is the compressor. That is what circulates the refrigerant through the A/C system and if it isn’t circulating the refrigerant, then the condenser isn’t cooling. 

This is a common issue after a long winter where the A/C wasn’t used (who need air conditioning when its 10 below right?). You can prevent this from happening by running your A/C once a month for a few minutes throughout the winter.  Many cars activate the condenser when the defroster is on, so check with your car ac repair shop about your car’s mode of operation. 


When all the components we’ve mentioned here are working, but your  A/C is blowing hot air, then it could be the electrical wiring. Anything from a blown fuse to frayed wiring will keep an A/C system from working as it should.  Your car ac repair technician can evaluate this for you and make any repairs or replacement needed. 

Why do we recommend that you take your car to a car ac repair shop for these issues? Because a professional car ac repair shop will have all the proper tools for car ac repair as well as the experience and knowledge. Remember, the A/C system is a complex system and recharging the refrigerant takes specialized tools and the knowledge to know when it has enough. 

Why did my car AC stop blowing cold air?

When a car air conditioner starts blowing mild cool air or warm air, you’re probably asking yourself, “Why did my car AC suddenly stop working?”.  It can be any number of things, some of which we mentioned above. Any of those things could be damaged, like the condenser we mentioned, or simply just worn out from use.  A few things that and car ac repair technician may find wrong with your car’s A/C could be any of these:

  • The Freon Leaked – a connection, gasket, or hose could be the culprit. 
  • Recharging Needed – all A/C units in cars will loose some freon/refrigerant over time. 
  • Stuck Blend Air Door – a small door that opens/closes the vent system could be stuck closed.
  • The  Compressor Isn’t Engaging – the heart of your car’s A/C system may need to be replaced.
  • Condenser – as we described earlier, where this part is located if vulnerable to getting blocked or broken. 
  • Electrical  – again, mentioned earlier, the wiring could be broken or frayed, or a fuse blown. 
adjusting car ac knob

What are the symptoms of a bad AC compressor?

The air conditioner compressor in your car is under a lot of stress. It gets turned on, turned off, and these puts a lot of wear and tear on it. After a few years, it can wear it out to where it doesn’t work anymore. A few warning signs that you may need to take your car into a car ac repair shop soon before the compressor is totally gone are: 

  • Strange Sounds: When the air conditioner in your car makes strange sounds, it could be a sealed bearing or a number of the components inside the compressor.  A trained car ac repair technician can diagnose those sounds and determine what is happening, or not happening.
  • Hot Air: When the A/C in your is turned on and blows hot air, this could be the compressor going out.  Again, have a car ac repair technician inspect the system and diagnose the issue. 
  • Fluid Leaking: Anytime your car has fluid leaking, it isn’t good, and that is especially true of the AC compressor. The internal bearings needs that pressurized fluid to work correctly. Your car ac repair technician can determine that is the problem and replace them if possible. 
  • Belt Skipping or Squealing: When your car air conditioning system has a loud squealing sound, it has a belt problem. Take your car to the car ac repair shop before you use the A/C again. 
  • A/C Compressor Clutch Stuck: The clutch on the A/C compress  allows the compressor to work from the engine power, but if that clutch gets stuck or seizes up, then it isn’t getting power. This is definitely something your  car ac repair technician will need to inspect.

Okay, so now you know some possible issues with the A/C system in your car. So, how much does it cost to get air conditioning fixed in a car? The range of  car ac repair costs will vary based on the make and model of your car, and the problem with the A/C. 

General ballpark pricing can range between $200 and as much as $800 or more. When it is the compressor, you can expect that to cost you as much as $1,000 and up.  To have the A/C recharged, that can average between $100 to $150. Need your car air conditioner repaired in Schaumburg, IL? Call 847-895-9131 today.