Does Coolant Affect AC Performance?

Is your car air conditioning system not cooling the cabin enough, especially during a hot afternoon? The problem may not be from the air conditioning system itself. There are other non-air conditioning system factors that could reduce your car’s AC performance.

If you have observed your air conditioning system performance reduces whenever you have low engine coolant; then you may be asking, does coolant affect AC performance? Does low coolant affect heat in a car? Does coolant temp sensor affect AC? What are the signs of a low engine coolant?

This article will answer all these questions and more. But first, let’s see the relationship between engine coolant and the car AC.

does low antifreeze affect ac in car

Is there any Relationship Between Engine Coolant & AC?

The engine coolant, also called antifreeze, protects your car from overheating. It does this by dissipating the heat in the engine and deploying antifreeze protection to keep the engine running at optimal temperature.

It also lubricates other cooling system components like the water pump, head gasket, radiator, and engine block water gallery, keeping them in good working condition. However, it doesn’t end there.

The cooling and air conditioning systems rely on the engine coolant for optimal performance. If the engine coolant becomes low, it’ll not properly dissipate the heat from the engine resulting into decreased AC efficiency. So, if you were asking, does coolant help cool your car? Or does antifreeze help air conditioner? The answer is yes.

When there’s an inadequate cooling capacity due to low engine coolant, the engine will struggle to stay at the optimal operating temperature. As a result, the engine may also struggle to carry the compressor, leading to poor ac performance.

Keep in mind, the AC compressor works with engine power to maintain proper cooling efficiency. If the engine coolant is low, it can cause the engine to overheat, stressing the AC compressor. This will cause the air conditioning compressor to underperform, reducing AC efficiency.

Does coolant affect air conditioning?

The direct answer is yes; engine coolant can affect air conditioning efficiency in several ways. Simply put, engine coolant can affect your air conditioning airflow, temperature, and humidity.

Since the coolant is responsible for cooling the AC’s airflow, low engine coolant can affect the AC airflow.

The proximity of your car engine to the cabin can affect the air conditioning system. While the coolant is meant to optimize the engine heat, it may heat the air conditioning system.

Low engine coolant can cause humidity issues in the system. If there isn’t enough moisture in the engine, it can cause the AC to dry up. Of course, you know what that means. It’ll affect the air conditioning performance.

However, several other issues could affect your AC performance. Low coolant is a tiny fraction of the possible causes of AC performance issues. Hence, do not limit your diagnosis to the engine coolant.

do you need coolant for ac in car

Signs of low coolant levels

The common signs of low coolant in car AC are:

How to check engine coolant levels

First, when checking the engine coolant level, allow the engine to cool down. If not, the coolant will shoot at you and may cause severe burns. If you have been driving for a while, the engine, coolant reservoir, radiator, and the coolant itself will become hot.

Don’t open the radiator cap or coolant reservoir cover when the engine is hot. When the engine is hot, the coolant is still under pressure, and it can be dangerous to open it then.

Open the hood and locate the radiator. The radiator is located at the front of the engine, close to the cooling fan. Also, find the coolant reservoir tank. You can identify it by tracing where the small water hose close to the radiator cap connects to. Consult your owner’s manual if you can’t locate it.

The radiator should be filled to the brim. If it’s not filled to the brim, add extra coolant. On the other hand, the reservoir has a low (L) and full (F) mark, and the reservoir is translucent. This means you can see the coolant level without opening the tank. The coolant should be at the full (F) mark or very close to it. If the tank is filled to the brim, then you have to reduce it and let it sit at the full mark. But if it is close to or below the low (L) mark, add more coolant until it reaches the (F) mark.

Simply put, to check your coolant level, allow the engine to cool down and then look at the reservoir tank; the coolant should be close or at the full (F) mark. If it is close to or below the low (L) mark, top it up, and reduce it if it is above the full (F) mark.

Final Words

If you have been reading to this point, you will no longer ask, is coolant used for AC, or does coolant affect AC performance?

To sum it up, your coolant can affect AC performance in several ways. It can affect your AC’s airflow, humidity, and temperature. The coolant in your car is essential in optimizing engine temperature and keeping the air conditioning system working as it should.

If you suspect you have a low engine coolant, you can easily check the coolant levels and top up or reduce it as needed, aided by the guidelines offered here. However, if you are unsure of what’s causing reduced AC performance in your car, consult a trained technician to diagnose and rectify the problem.

Osuagwu Solomon

Osuagwu Solomon is a certified mechanic with over a decade of experience in the mechanic garage, and he has over five years of experience in the writing industry. He started writing automotive articles to share his garage experience with car enthusiasts and armature mechanics. If he is not in the garage fixing challenging mechanical problems, he is writing automotive repair guides, buyer’s guides, and car and tools comparisons.

Recent Posts