Can the air conditioning be left on while the car is running?
4 Answers
It is possible to keep the air conditioning on while the car is running, but it is not recommended to do so frequently. On one hand, it leads to higher fuel consumption, and on the other hand, idling can cause the engine to accumulate carbon deposits more easily, which may degrade engine performance over time. Tips for using air conditioning: After the car has been exposed to the sun for a long time, you should first open all four doors and the sunroof to allow air to circulate inside the car for about 3 minutes. This will quickly lower the interior temperature, making the air conditioning more effective when turned on. Using the recirculation mode blocks hot outside air, creating a sealed space inside the car, allowing the air to circulate rapidly under the effect of the air conditioning for faster 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 about 5 minutes before parking to protect the engine and save fuel. Hazards of prolonged idling: When the 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 carbon monoxide levels inside the car, which can lead to carbon monoxide poisoning or even death if passengers are present, potentially causing safety accidents. Therefore, it is important not to keep the windows completely closed. Instead, open them slightly to maintain air circulation between the inside and outside of the car.
I often drive with the air conditioning on, especially in the summer. It's fine to keep the AC running while the car is on, but there are some details to note. Prolonged idling with the AC on can lead to carbon buildup in the engine, and fuel consumption will noticeably increase—burning an extra one or two liters per hour. Additionally, it puts a heavy load on the battery, especially in older cars, which may drain the battery prematurely. I recommend turning off the engine if waiting for more than ten minutes, opening the windows for ventilation every half hour when using the AC, and regularly cleaning the AC filter. Never keep it running for long in tunnels or underground garages, as exhaust fumes may enter the cabin.
From a technical perspective, it is feasible to turn on the air conditioning after starting the engine, but continuous operation puts a burden on the compressor. The compressor is driven by the engine belt, and prolonged operation may cause excessive belt wear. The condenser is also prone to frosting under long-term high load, reducing cooling efficiency. It is recommended to use it intermittently, such as turning off the air conditioning for ten minutes after running it for half an hour, allowing the system to rest. At the same time, pay attention to the coolant temperature to avoid overheating. During regular maintenance, remember to check the refrigerant pressure, as leaks can lead to insufficient cooling.
Running the air conditioner continuously increases fuel consumption significantly, with an additional 1.5-2 liters of gasoline consumed per hour while idling. This not only costs more money but also leads to higher exhaust emissions, which is less environmentally friendly. I choose to use the air conditioner only when necessary, opting to open the windows for ventilation when the temperature is not too high. If prolonged use is unavoidable, switching to recirculation mode can save 20% on energy consumption. If I have to wait in the car for more than five minutes, I turn off the engine and step out to avoid unnecessary fuel waste. This habit helps me save a considerable amount on fuel costs each month.
