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Does Coolant Affect Air Conditioning? (Read This First!)

Apart from our homes, our vehicles are the place of our comfort and long residence. Our homes are equipped with appliances and facilities that provide us with the utmost comfort hence we look for similar comfort in our vehicles as well.

But similar to our homes, our vehicles need maintenance as well – we will cover that information in the sections below.

Does coolant affect air conditioning?

Air conditioners are indirectly affected by a chemical called the coolant. The coolant functions by absorbing the excess heat from the interior of the vehicle and transferring it to the outside, thus keeping the interior cool. Any change in this coolant will affect how the air conditioning performs.

A heat transfer fluid called the coolant is an essential component of the air conditioning system which circulates throughout the car engine and prevents the engine and the other components of the vehicle from overheating.

The coolant achieves this feat by absorbing the excess generated inside the car and then discharging this energy to the outside. This keeps the vehicle from overheating and protects its internal components as well as helps the air conditioner to cool.

However, the variation in the coolant temperature can alter how the air conditioner controls the air temperature.

If the temperature outside is hotter, then the coolant has to flush out the excess heat but if there has been a change in the coolant such as coolant flushing, then this difference will show significant performance changes in the air conditioner and the extent of heat reduction.

The coolant is a fluid that is usually green, orange, or blue in color that is poured into the car radiator. The radiator allows the coolant to circulate to and from the engine – keeping the temperature constant.

During the summer, the engine heats up more and causes bad boiling, which is why the coolant is often mixed with water when poured in.

You can notice how a coolant affects air conditioning when there is a radiator leak. These leaks lead to loss of coolant and their level gets lowered when using the air conditioner which prevents the air conditioner from drawing out the heat from the inside.

Will low coolant or antifreeze affect AC?

Coolants are a mixture of 50:50 water and antifreeze which serves to maintain the balanced temperature of the engine and the passenger cabin. A low level of coolant or antifreeze will show several symptoms and one of them is a dysfunctional AC.

If you notice that the AC’s Auto mode is failing to detect the cabin temperature and adjust it then it is a probable sign. Another sign is during winter when you turn on the heater, you will only get cool air blown out.

This is because low levels of coolant or antifreeze are not in sufficient amounts to be circulated around and distribute heat.

Does the coolant level affect ac temperature? Will coolant make my ac colder?

The effect on the AC temperature depends on the extent of the coolant’s level. Since the radiator functions by circulating the coolant mixture throughout the system and transferring heat, the lack of this coolant will definitely cause some fluctuations in the AC temperature.

Low coolant levels will cause the AC temperature to remain high during summer or cold during winter – since the distribution of heat will fail to occur. However, normal to high levels of coolant will have no change and will not even contribute towards making the AC colder.

Does adding engine coolant help or fix ac?

A common misconception people have is that an engine coolant is a direct reason behind the functioning of an AC. But in reality, they are just remotely connected, and adding or changing the engine coolant will have little to no effect on fixing your AC.

The coolant helps in heat loss of the engine but not the passenger cabinet. Although having an engine coolant does aid the AC in keeping the cabinet cool, it does not directly impact the AC. This is why flushing your coolants or changing them will not help fix your AC.

Can low engine coolant or antifreeze affect air conditioning?

Low levels of engine coolant or antifreeze will not stop air conditioning but will result in inconsistent temperature variations. The engine coolant cools the engine down from overheating but does not run directly into the air conditioning components.

Whereas the air conditioning of the passenger cabinet is controlled by a separate unit. Therefore, with low engine coolant or antifreeze in the radiator, the AC in the cabinet will still function but the sensors will no longer function properly.

And so you will experience a change in the AC temperature but it will still function.

Does coolant affect the heater in a car?

A coolant drives the heat away from the engine towards the radiator to blow the heat into the cabinet when the heater is turned on. During summer, this fluid dissipates the heat outside, but in winter you can dissipate the heat into the cabinet.

The coolant acts as a medium of heat transfer and therefore if your car has low levels of coolant then your heater will not blow hot air.

Can low engine coolant cause the heater not to work?

You might notice that your heater is blowing cool air to which low engine coolant might be the cause. During winter when you turn up the car heater, the coolant mixture gets transferred away from the engine and towards the heating core.

The heating core warms up and heats up the coolant around it. Initially, you will feel cool air getting blown at you since the heating core is not hot enough, but a few moments later you will feel hot air flowing in.

However, if the cool air still flows after a good 10 minutes then there is a problem with the heating mechanism – there is insufficient engine coolant to heat up the air.

How do you know if your AC is low on coolant?

Other than explicitly checking the radiator reservoir, there are several symptoms you may notice that could signify that there is a low coolant level. One of the most obvious things you will notice is that your vehicle is overheating.

Since a coolant keeps the temperature low, your AC will not cool as much as it used to.

You will also notice that your AC behaves strangely when you activate auto cooling mode as it fails to detect the cabinet temperature properly.

As the coolant is responsible for detecting temperatures, the low coolant level will also cause the temperature sensor to be faulty and the AC to malfunction.

How to check the AC coolant level in a car?

If you notice the symptoms of having low levels of AC coolant you should check the AC coolant level first since it is the easiest to test. The coolant is a mixture of water and antifreeze that is fed to the radiator.

So you should check for the location of the radiator reservoir usually located to the side under the car hood.

First, you should open and check the radiator for the coolant, if not visible then head to the radiator reservoir. The translucent reservoir has markings on its body thus you can tell if the level is low or not.

How often to change the coolant in a car?

If you notice abnormalities in the heater or air conditioner then it is the ideal time for you to change the coolant of a car. However, it is recommended that you check the coolant level once every two weeks or before a long trip if the coolant needs changing.

The coolant often does not require change unless it has gone bad from mineral deposits or rust or if the level is low.

You can visually assess the contamination of the coolant by using a syringe to take out some of it from the radiator reservoir and compare it with its original color.

Does the coolant temp sensor affect ac?

The coolant temperature sensor is responsible for detecting changes in temperature and sending signals to the system for temperature adjustment. However, faulty coolant temperature sensors will affect how the AC operates.

The Auto mode of an AC sets the internal temperature by assessing the initial temperature. The faulty temperature sensor will fail to take the readings correctly and the Auto mode will not work.

Another problem similar to this will arise is that the AC will be unable to provide consistent cooling and have consistent temperature fluctuations.

Besides that, the temperature sensor will fail to take accurate temperature readings and display incorrect readings on the temperature gauge.

Final thoughts

The coolant plays a significant role in affecting the air conditioner. The coolant mixture absorbs the surplus heat from the engine and the interior and flushes it out through the radiator. Therefore, any changes to the coolant will prevent the radiator from proper air conditioning.