Does Running the Air Conditioner While Idling for a Long Time Affect the Car?

[DelConnor]

Running the air conditioner while idling for a long time does affect the car. Using the air conditioner increases fuel consumption, and prolonged operation can lead to carbon buildup in the engine. When the engine is running, if the gasoline in the cylinders does not burn completely, it produces high concentrations of carbon monoxide. If this carbon monoxide leaks into the car's cabin, it can gradually accumulate and reach dangerous levels, potentially causing poisoning and, in severe cases, even suffocation and death. The air conditioning system is designed to ventilate, purify, cool, and heat the air inside the vehicle. It provides a comfortable environment for passengers, reduces driver fatigue, and enhances driving safety. However, prolonged idling with the air conditioner on not only accelerates engine wear but also keeps the air conditioning system in recirculation mode, which can lead to increasingly stale air inside the car, raising the levels of harmful gases and posing risks to human health.

[VanAnthony]

When I drive myself, I often encounter situations where I idle the car to wait for friends or take a break with the air conditioning on. This habit is actually not good for the car, especially affecting the health of the engine. In idle state, the engine operates at low efficiency, and turning on the air conditioning increases its load, causing the oil temperature to rise. Prolonged idling with the AC on may lead to increased wear on parts and more carbon buildup. Once, during a hot summer day, I idled with the air conditioning on for half an hour and found the hood extremely hot when I got out. Later, a minor issue was detected in the cooling system, reminding me to regularly check the temperature sensor and oil change intervals. It's best not to idle with the air conditioning on for more than 15 minutes. If you must wait for a long time, driving a short distance to allow air circulation can protect the engine's lifespan and save some fuel costs. For maintenance, I recommend cleaning the air conditioning system every six months to avoid dust accumulation affecting cooling performance.

[ClaireLynn]

From the perspective of the battery, idling with the air conditioning on for too long is indeed a problem. This is because the alternator's output is limited at idle, while the air conditioning compressor, headlight fans, and other components consume a significant amount of power, causing the battery to undergo repeated charging and discharging cycles. For older vehicles or during winter, the battery is more prone to draining or damage, which can shorten its lifespan.

I once had an experience while camping outdoors where I left the air conditioning and music on for less than an hour, and the car wouldn't start afterward. I ended up spending a few hundred dollars to replace the battery. The lesson learned is that it's best to limit idling with the air conditioning on to no more than 20 minutes, or to turn off the air conditioning before shutting off the engine.

As an additional note, if your car has USB charging devices, be cautious not to overload the battery. For daily use, it's recommended to let the engine run for about 10 minutes to recharge the battery before idling or resting, to maintain the battery's health.

[Hall]

Keeping the air conditioning on while idling for long periods can significantly increase expenses. I've observed the fuel consumption, and idling may use about 0.5 liters more fuel per hour, leading to a noticeable rise in costs. For example, during summer traffic jams when I often keep the AC running while stationary, my monthly fuel expenses increase by several dozen yuan. This doesn’t even account for the hidden wear on the engine—if overheating leads to repairs, the additional costs could be much higher. It’s best to use the AC only when absolutely necessary and for short durations. Alternatively, consider rolling down the windows slightly for natural airflow to cool down. From an environmental perspective, idling produces more exhaust pollution, so reducing usage helps both personal savings and minor eco-friendly efforts.