Can the air conditioning be left on while the car is running?
3 Answers
It is possible to keep the air conditioning on while the car is running, but it is generally not recommended to do so frequently. This is because it can increase fuel consumption and may also lead to carbon buildup in the engine. Tips for using the air conditioning: After the car has been exposed to the sun for a long time, open all four doors and the sunroof to allow air to circulate inside the car for 3 minutes. This will quickly lower the interior temperature, making the air conditioning more effective. Using the recirculation mode blocks hot outside air, creating a sealed space inside the car where air can circulate quickly under the influence of the air conditioning, leading to rapid cooling. Once the interior temperature has dropped, it is recommended to switch to the fresh air mode every 30 minutes to purify the air inside the car, then switch back to recirculation mode after 5 minutes. Turn off the air conditioning 5 minutes before parking to protect the engine and save fuel. Hazards of prolonged idling: When a car is idling, incomplete combustion of gasoline produces a significant amount of carbon monoxide. The longer the idling time, the higher the concentration of carbon monoxide around the vehicle. Prolonged idling can result in extremely high levels of carbon monoxide inside the car, which can lead to carbon monoxide poisoning or even death if someone is inside, potentially causing a safety incident. Therefore, it is crucial not to keep the windows completely closed; instead, leave a small gap to ensure proper air circulation between the inside and outside of the car.
I usually keep the air conditioning on and idle while waiting for someone in the car during summer, which feels very comfortable and convenient, especially when the temperature exceeds 30 degrees and I have to wait for a friend by the roadside for more than ten minutes. However, doing so will increase fuel consumption. Once, I waited with the air conditioning on for half an hour at the entrance of a shopping mall, and the fuel gauge dropped significantly, costing me an extra few dozen yuan in fuel expenses. Although the impact is not significant, my wallet can't handle it in the long run. It's recommended to use it only when necessary, such as to avoid heatstroke, and never leave it on for too long in a garage or enclosed space to prevent the accumulation of carbon monoxide, which poses a safety hazard.
From a technical perspective, it is entirely feasible for the car's air conditioning to run continuously while the engine is on, as the compressor is driven by the engine. However, prolonged idling increases fuel consumption and may accelerate engine carbon buildup, leading to performance degradation. I have repaired some older car models where frequent and prolonged use of the air conditioning also affected battery life due to the continuous power draw from the fans. Modern cars are designed to be more durable, but it is still advisable to use the air conditioning moderately and manage its runtime properly to ensure vehicle health.
