Why should the car's air conditioning be recirculated?

As every year, the month of June marks the start of the hottest weeks, and car air conditioning systems become indispensable elements when traveling by car, especially during the central hours of the day. Curiously, however, the air conditioning system is one of the great unknowns for most car owners in our country, as are the basic functionalities needed to optimize its performance.

Now it's been a while we already explained some tricks and tips for efficiently using the car's air conditioning during the summer months, such as parking in the shade whenever possible, opening the windows and doors before starting the engine to dissipate the heat inside the vehicle, waiting a few seconds to turn on the cooling system, or driving at a temperature equal to or higher than 21 degrees Celsius, as below this figure fuel consumption increases by 30%.

Having the cooling system in good condition is a key road safety element during the summer months, as with temperatures above 35 degrees our brain suffers effects similar to driving under the influence of alcohol: our reaction capacity decreases by more than 20%.

Surprisingly, not everyone is aware of a feature of their vehicle's cooling and air conditioning system, such as the air recirculation button, which allows for more comfortable travel, protects us from particles and bad smells, and also allows us to increase energy efficiency.

The operation of the vehicle's cooling or heating system is simple: when we turn it on, the car absorbs air from the outside, filters it, and cools (or heats) it before allowing it to enter the cabin. Once we feel comfortable inside the cabin, it is advisable to activate the air recirculation function, which will allow the air from the cabin itself to be reabsorbed, filtered again, and used to circulate it again inside the car. With this function activated, we will also prevent the entry of bad smells or particles when passing through industrial areas, for example, while also making it possible for the car to cool down more quickly and for fuel consumption to be lower, thanks to the fact that we relieve the vehicle of having to take in air from the outside, which is always warmer, and cool it down to the desired temperature.

However, this recirculation system requires some precautions. Firstly, the filters of the ventilation system must be clean, as the presence of bacteria can contaminate the interior of the car. Likewise, it is not at all advisable to smoke inside a vehicle with the cooling system activated, for obvious reasons. Finally, it is worth noting that this recirculation system can cause drowsiness while driving, as it forces us to breathe the same air many times, and can ultimately cause the car windows to fog up, especially during the winter months.