Does Air Conditioner Affect Car Performance?

Does Air Conditioner Affect Car Performance?

Nowadays, most cars come with AC as a standard feature. In the past, people used to get it installed in their cars, and it was expensive.

The HVAC system is a good addition to new cars because it helps to stay cool when it’s hot outside. One thing should be clear that like other accessories alternator, power steering pump, and water pump, AC also gets power from the engine by using a serpentine belt. Now, the question is, does air conditioner affect car performance? 

The simple answer to this question is, yes, air conditioner puts an inevitable pressure on the car’s engine, so, it affects car performance. In some countries, the car must be switched off during idle mode to minimize pollution.

How Does Air Con Draws Power?

An air conditioner isn’t different from other accessories; it will take power from the same source your whole car takes, and that source is the engine.

However, the additional load of AC puts a significant load on the engine. When the energy is used for cooling, it divides the engine power into two parts. It affects the throttle of the car. 

How Much Pressure Does AC Put on the Engine?

The air conditioner is powered by the engine, and when it takes power from the engine, the energy is divided into two parts. Now the question is how much pressure AC puts on the engine? The amount of effect of AC on the engine and car’s performance depends on:

  • Condition of the engine
  • The manufacturing date of your car
  • Power of the vehicles air conditioning system 

When the car is new, it will have less effect on the engine. Moreover, all the conditions mentioned above have an inverse relationship to the amount of effect on the car’s engine.

How to Minimize the Performance Issues Due to HVAC?  

AC will definitely affect a car’s performance, but you can minimize these issues by the following practices:

  • Use the AC feature when it’s too hot outside. Please turn it off when there is no need. 
  • Set the AC temperature according to the heat outside of the vehicle. 
  • When you are turning the ignition on, keep your AC switched off. 

In these ways, you can minimize the impacts of AC on the performance of the cars. 

How the Air Conditioning System Affects the Engine?

Your engine powers the HVAC system, and it drives power from it during operation. So, it can affect the engine performance. You can notice a significant increase in RPM of a car when the compressor kicks on. So, the question was, does air conditioner affect car performance? Yes, it affects. Another question that arises in mind is how much power it draws? There is no straightforward answer to this question. Answer to this question depends on the condition of the engine, make and model of the vehicle, condition of the HVAC system, and many more. 

Vehicles that have smaller engines will have a noticeable impact of AC on them. A four-cylinder engine will be affected more as compared to the V8 engine, even the identical amount of power is drawn by the AC between the two cars. 

Factors Affecting the AC Load on the Engine

There can be lots of factors that affect the AC load on the engine, so let’s have a look at these factors.  

  • Climatic conditions
  • Climatic conditions are all about outside environmental conditions such as temperature, relative humidity, and pressure. These climatic conditions have a significant impact on determining the AC load on the engine. Lots of other parameters, such as solar incidence angles, surrounding radiant heat, glazing properties, and air velocity affect the performance of the HVAC system. When the difference between these factors is greater, there will be more loads on the engine. When the temperature difference between outside and inside is more, the compressor will have to do more work. When it takes more power, it means it will have a severe effect on the engine and vice versa. 

  • Cabin conditions
  • Cabin conditions also play a major role in determining load on the engine. The load is affected by the number of passengers in the vehicle. There can be other parameters, such as clothing, metabolism rate, and thermal sensation of the passengers. So, all the factors will have some effect on the engine’s performance. 

  • Compressor speed
  • Most of the compressors are mechanically driven. Compressor speed has a direct relation to the engine’s performance. When the speed is high, it will put more loads on the engine. 

  • Difference between outside and inside conditions
  • When there is a large difference between the inside and outside conditions, the compressor has to do more work to isolate the cabin from the outside environment. If the difference is smaller, the compressor will have to do less work and will draw less power from engine for cooling purposes. 

  • The overall efficiency of the AC system
  • Lots of factors affect the overall efficiency of the air conditioning system, such as:

    • Types of compressor used
    • Type of condenser used
    • Type of evaporator used
    • Type of refrigerant used
    • Vehicle speed

    All these factors affect the overall efficiency of the air conditioning system and engine performance. 


    Does air conditioner affect car performance? So a simple answer is yes. AC affects car performance, but impacts of AC on the car’s performance will be different. You might have listened that no good comes without any loss. As temperatures are increasing globally, so the HVAC system in cars becomes crucial. Most people don’t drive their cars until they don’t turn on the AC. 

    People want to remain cool, but at the same time, they also want to know does air conditioner affect car performance? Yes, it drives power from the engine so that it will impact the engine’s performance. The effects of AC on engine depend on lots of other factors as well. Inside and outside temperature difference plays a major role. Climatic conditions are also important. Compressor speed also has a significant impact on the engine’s performance. So, yes, we can say that the air conditioner affects car performance.  

    Efforts have been made to get the information as accurate and updated as possible. If you found any incorrect information with credible source, please send it via the contact us form
    Author: Sky Hoon
    He loved the future of self driving car and cannot wait for one. In the meantime, he loved to read up all about car and components like a computer.
    Read His Personal Blog
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