Does Coolant Affect Air Conditioning

The job of a coolant may seem quite obvious. As its name suggests, it is there in your car to cool something. If your car’s air conditioner is not giving proper service, it may be tempting to think the coolant is at fault. Technically it is; however, the mechanism is more complicated than you think.

The job of the coolant is to absorb heat from the car’s interior, that is, the engine and other parts. Then it dissipates the heat to the outside, preventing the engine from overheating. Low coolant can affect the AC’s functionality as the unit controlling the AC is inside. However, it is an indirect effect as the coolant is directly not involved in your AC’s cooling abilities.

It is good to know if your car has sufficient coolant or not. And if your AC is showing some problems, keep reading as we discuss what to do in such circumstances.

Does Coolant Affect Air Conditioning

What is a Coolant?

A coolant is a chemical whose job is to cool the insides of your car. It goes into the radiator and comes in different colors: blue, green, and sometimes pink. This chemical circulates throughout your car’s interior, taking away heat from engines, cylinders, and pipes. Then it dissipates this built-up heat outside. The water inside the engine won’t start boiling, and the engine is kept from overheating. It is a mixture of anti-freeze and water, each component making up half of the coolant.

It should be clear that if your car doesn’t have enough coolant, the engine will overheat quickly. But how does that affect your AC? Let’s find out.

How Does Coolant Affect Air Conditioning?

Low levels of engine coolant may not directly affect the AC unit, but it can have some influence on its performance. If there is low coolant, the engine would get hot quickly enough. That could hinder the AC unit’s performance as well. If your car has sensors that can control the AC’s temperature, they may all but cease to work properly. That way, you will be able to notice some changes in the AC’s performance.

However, the air conditioning unit has its own cooling chemical. It is commonly known as Freon, the chemical in your car’s air conditioning system that helps cool the air. Low Freon would affect the temperature, humidity, and airflow of the interior of the car. If the unit has low Freon, the AC would deliver hot air instead. As well as that, the Freon also controls the airflow. If there is little Freon, then too much hot air may get into the AC unit. And as a result, the unit’s temperature and humidity are negatively affected. 

Finally, the coolant also controls the humidity. If there is not enough Freon to make the unit sufficiently humid, it can downgrade the air conditioning. Too little humidity can dry out the passenger’s skin and mouth.

How Do I Know if My Car is Lacking Coolant?

There could be several indicators that your car may lack coolant. First off, if your AC is underperforming than usual, that may hint that the car is lacking coolant. As well as that, if you notice your car’s engine is overheating too quickly you should look if the coolant is working properly. 

A radiator leak can cause a drop in coolant level in your car. Any puddles around your car can give a hint of a leaking radiator. Moreover, in the air conditioning unit, if you notice rust around the reservoir, then it means the coolant needs a change. The reservoir is a translucent container located under the hood of your car.

Some Other Problems That May Cause the Air Conditioner to Work Properly.

It is very possible that your AC is not delivering cool air for some reasons unrelated to the coolant quality or supply. 

The AC compressor of the car may not work properly. It can happen if there are some electrical circuitry faults or something wrong with the compressor itself. There could also be ice piled up within the compressor due to a coolant leak. 

Another component of the cooling system is the blend air door. Its job is to let cool air into the unit. If that part is not properly functioning, it could be the reason your AC unit is not blowing out cold air. On the other hand, the AC’s fan may not properly work. That way, the AC may be incapable of blowing cold air. You would realize this problem when you notice cold air is coming out but it is not blowing with force.

For all such cases, it is better if you get some professional help. You may be able to change the coolant or Freon by yourself but these are technical matters. You would be better off if a professional handles this.

Finally, the car’s age could be a significant factor. If your car is too old, like over a decade, its AC unit may fail to give further proper servicing.


Does low engine coolant affect AC performance?

It would not have a direct effect. However, having low coolant can be dangerous in other ways. The engine may suffer dangerous overheating because of low coolant levels. The AC’s performance may be hindered significantly, as the AC unit may not be cooled by the coolant properly. But, flushing the coolant of your car would not enhance the performance of the AC unit, nor will it help increase AC temperature.

When do I change my Freon or coolant?

Ideally, you would not need to change them at all. The chemical works in a recycling system, absorbing heat, dissipating it, and repeating. But over time, leaks or mineral deposits, or rust can pester with the car’s ability to perform. You should most definitely change the coolant or have its level checked in such cases. If you plan a long journey ahead, you should have them checked in advance.

What is anti-freeze?

Anti-freeze is a coolant component, which makes up 50% of it. Anti-freeze helps prevent your car’s engine and other components from freezing in harsh winter periods. It supplies warmth to the internal parts of your car so that they do not freeze. Do not be confused; the coolant’s job is to prevent both overheating and freezing.

Bottom Line

We understand that it can be quite frustrating when your AC would not sufficiently cool your car. While it can be tempting to think that the engine coolant itself is to be blamed, the matter is not that simple. We have discussed that the engine coolant may play an indirect part. 

However, the lack of Freon is the culprit. The chemical inside the air conditioning unit helps control the temperature, humidity, and airflow inside the car. But having the coolant checked is equally essential as well. Look out for leaks, rusts, or overheating issues in your car. We hope that our article has helped you decide on your next step to fix your issue.

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