Does idling with the AC on harm the car?
3 Answers
Yes; The air conditioning compressor is driven by the engine, while the blower fan is powered by the battery. When the car is idling, it may not necessarily charge the battery. Excessive power consumption by the blower fan can lead to long-term battery depletion. Hazards of idling with the AC on: 1. Engine damage: Starting the AC immediately after the engine starts increases the engine load, which can damage the engine over time. Turning on the AC when the interior temperature is very high makes it difficult to cool down quickly. Instead, open the doors and windows, turn on the external circulation to release the hot air inside. Once the interior and exterior temperatures are similar, close the windows and doors, turn on the AC and switch to internal circulation. This method lubricates the engine and improves AC cooling efficiency. 2. Carbon monoxide poisoning: During prolonged traffic jams or waiting, if the AC is left on, the engine remains in idle mode, which also places a heavy burden on it. Moreover, incomplete fuel combustion during idling produces high concentrations of carbon monoxide. If the surrounding air circulation is poor (e.g., in a garage), the carbon monoxide emitted by the engine can enter the car and cause poisoning to the occupants.
Leaving the air conditioning on while the car is idling can indeed harm the vehicle. When the engine is idling, it struggles to power the air conditioning compressor, and prolonged operation increases mechanical load, potentially causing abnormal engine temperature rise and premature wear of piston rings or cylinder walls. Additionally, the battery is heavily drained by the fan. If the car is old or the battery is in poor condition, it can easily deplete energy, making the next start difficult. I've seen many similar cases at work, with batteries failing after just one summer. It's best to avoid this, especially on hot days—turn off the engine if parked for more than a few minutes, opting to open windows or rest in a shaded area instead. This protects the car and saves fuel and money. If air conditioning is absolutely necessary, checking the cooling system and battery status within a minute or two after starting is safer.
Every time I park and turn on the air conditioning, my beloved car seems to complain. I used to ignore it, but it resulted in severe battery drain and costly repairs. The air conditioning relies on the engine, and when parked, the engine runs at low RPM, making the compressor work harder, significantly increasing fuel consumption, and allowing exhaust fumes to accumulate nearby. If the car interior is sealed, it's easy to inhale harmful gases. A friend of mine even faced the risk of fainting. Now, I only dare to use it briefly, like waiting for someone for a minute or two, otherwise, I get out to rest or lower the fan speed. Remember, prolonged use of air conditioning also negatively affects engine maintenance, accelerating issues like rubber hose aging and fluid leaks. Regularly checking the air filter can provide slight relief, but it's still not as healthy as turning off the engine.
