Does Coolant Affect Air Conditioning (A.C.)?

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Coolant does tremendous help to your car’s radiator. But do you wonder if that same coolant affects your air conditioning? Do you want to know whether it affects your car’s air conditioning?

In this article, you’ll get the right and well-informed answers to these. In addition, you’ll find details about the relationship between the coolant and the AC.

You’ll also know how the coolant affects your vehicle’s air conditioning system. You’ll also find out whether low coolant is detrimental to your vehicle radiator or not.

Stay tuned to the signs to be on the lookout for when you have a low coolant in your vehicle’s radiator.

Does Coolant Affect Air Conditioning (A.C.)?

So, if you ask me: ‘does coolant affect air conditioning?’ I will answer you yes. Coolant indeed affects the proper functioning of your car’s air conditioning of your car.

It affects the airflow, humidity, and temperature of the air in your air conditioner (A.C). It is usually orange, blue, or green fluid that is added to the radiator of a car.

This is needed to help improve the working conditions of the Air conditioner.

How Coolant Works And Affects Air Conditioning

As a part of the entire AC system, the coolant serves as a liquid agent of heat transfer. The coolant mixes with air in the right proportion.

After, it distributes itself through the car engine. The coolant helps to cool the cylinders. Besides, it reduces the amount of heat that is capable of causing engine overheating.

Your car gives off a lot of heat. The coolant absorbs the heat and transfers it to different parts of the car engine.

This is to ensure that the heat doesn’t damage the interior of your vehicle. As the AC works, the coolant changes when the heat gets to it.

As the coolant heats up, the capacity of the air conditioner in heat reduction comes down.

When the coolant level is low, the performance of the air conditioning system drops. Your auto radiator needs the coolant for your air conditioner system.

In other words, the effective and efficient working of the AC depends on the coolant. The low presence of coolant in the car alters the following conditions in your A.C:


Typically, the moisture rate in your car’s AC depends on the level of the coolant. When there is a shortage of coolant in your vehicle, the air conditioner distributes dry air.

Furthermore, the dry air being circulated leads to dryness of the mouth and of the skin of people in the car.


No doubt, a low coolant in the radiator generates overheating in the interior part of your vehicle. This is because your coolant provides immediate rejuvenating by cooling.

This way, your car’s engine will work optimally. However, once the coolant level drops, the amount of hot air released behind the engine block increases.

This can ultimately lead to overheating of the internal components of your car. Also, driving with low coolant in an automobile can burn down your car’s radiator and its other internal components.

The flow of air

The coolant is also responsible for regulating the rate of flow of refreshing air present in your air conditioning unit.

So, having low coolant in your vehicle would let hot air proceed into your A.C unit instead of the cool air that is required.

Meanwhile, lack of proper flow of air and high heat in your A.C would cause high humidity and high level of temperature.

This could pose a great danger to not just the lifespan of your automobile but also could make voyagers suffocate, hot and uncomfortable.

Does low Engine Coolant Affect AC?

Yes, it is affirmative that low engine coolant does affect the air conditioner of your car.

This is because the engine coolant is the chemical needed by your air conditioning system to keep it running smoothly and effectively.

It absorbs heat from your vehicle and transfers it somewhere else to protect your automobile’s engine.

When there is a low presence of antifreeze in the coolant in your truck, it affects your air conditioner indirectly.

This is done by overheating your automobile’s engine and when this occurs, a thorough checkup of your vehicle is required.

Also, a fresh radiator and antifreeze are needed and the mechanic would need to clean the entire radiator before he puts it in it.

Additionally, your car’s radiator might have corroded and needs to be changed. When a radiator is rusted, it is as good as useless because instead of helping the whole part of the vehicle, it would wreak havoc on it instead. Therefore, always check out the radiator now and then.

Signs Of Low Coolant In Your Car

It is very crucial for you to know the signs and to pay attention to what comes with having low coolant in your car’s radiator.

This is so that you can quickly figure out what to do before low coolant causes some damage to your automobile.

Therefore below are some of the signs you’re likely to encounter to know that there is a shortage of coolant in your vehicle

Hot/Warm Air Condition

One of the visible signs of low coolant is a warm air conditioner after your switch on the AC. The most basic sign of low coolant in your car’s radiator is the hotness or warmness of the AC.

You’ll notice this anomaly when your vehicle’s A.C. gives off a temperature below 68°F. Just as we’ve mentioned earlier, the coolant helps to promote the cool flow of air in your air conditioning.

Therefore, having such an air temperature in your car indicates that you have low coolant in your automobile’s radiator.

Low Or No AC Sound

You can also notice that the air conditioner’s clutch does not give off any sound when it’s turned on.

After switching your AC on, a click sound is given off that shows the engagement of the clutch.

Thus, if the coolant level is too low, clutch engagement would not be possible. Also, this implies that there is not going to be any working activity in your A.C.

Compressor Won’t Engage

That your AC compressor won’t engage when there’s a low level of coolant is a no-brainer.

But note that there is a wide range of things that can be responsible for the compressor not engaging.

For instance, the compressor circuit may be experiencing an electrical defect. But trust me, a low coolant level is the #1 culprit when the compressor isn’t engaging.

This is because when the AC is low on coolant, it can cause overheating.

Visible Refrigerant Leaks

This is also a great sign to never ignore in your car’s air conditioning system. When coolant leaks, it goes out as a thin and greasy liquid.

This leak usually takes place around your car’s compressor. It can also happen in the interior part of the or also at the bottom part of your car.

Do not take this sign for granted. It’s serious and you shouldn’t use your car AC if you’ve not fixed the leak.

A professional technician will help you resolve it to prevent further damage to your car.

Why Is My Car AC Not Blowing Cold Air?

So, truth be told, I expected this question to come up. You might want to know why your AC isn’t blowing cold air.

But did you take note of what I said when I was explaining the effects of low coolant or refrigerant?

Let me say it now that your AC will continue to blow hot air once your car radiator is running on a low refrigerant.

What happens is that low refrigerant will cause the air conditioner not to operate. In other words, the clutch that’s supposed to kick in won’.

The result is that the compressor cycle will be incomplete as there is a shortage of the needed amount of pressure in the system. When the compressor cycle is not complete, the AC will not blow cold air.

Final Thoughts

It’s worth reiterating before I draw the curtain on this session that a lower-than-normal level of coolant is dangerous to your AC.

And not only your AC but low coolant level can also cause serious damage to some expensive car components.

The lower the coolant, the lesser the time it takes for it to cool as it gets in the radiator.

Normally, the coolant is supposed to cool for a few minutes in the radiator before channeling into the AC system.

But when this doesn’t happen, the result is inefficient engine cooling and AC not working as it should.

Knowing the effects of a coolant on your car’s air conditioner is just as important as owning the vehicle.

This article equips you with the right information about your coolant. Next time, you can prevent any issue that may want to arise.

I’m convinced that you now know a great deal about AC coolants and their effects. I’ve also equipped you with how to know when there is a shortage of them in your car, and more.

Moreover, drop your questions relating to your car’s Air conditioner coolant or coolant.