Does Using Air Conditioning While Parked Damage the Car?

[StMadelyn]

Using air conditioning while parked can indeed harm the vehicle. Keeping the car idling with the AC on for extended periods leads to several issues: it increases fuel consumption, accelerates engine carbon buildup, and in poorly ventilated areas or garages, may cause carbon monoxide poisoning for occupants. Below are the specific hazards of leaving the air conditioning on while the car is parked: 1. Carbon Monoxide Production: When the engine runs, incomplete combustion in the cylinders can produce high concentrations of carbon monoxide. While driving, air flow through the AC system ensures low CO levels inside. However, when parked with AC on and windows closed, stagnant air allows CO from the exhaust to accumulate, potentially leading to poisoning or fatalities. 2. Battery Drainage: Although the AC compressor is engine-powered, the blower fan relies on the battery. During idling, the alternator may not sufficiently recharge the battery, causing prolonged power depletion from continuous blower operation. 3. Engine Carbon Deposits: Extended AC use while idling increases fuel consumption and significantly contributes to carbon buildup within the engine components.

[Jade]

Does running the AC while parked harm the car? I've been driving for over 20 years and often turn on the AC to cool down during red lights or while waiting in summer. Actually, it doesn’t harm the car much because the AC compressor is driven by the engine—as long as the engine is running, it works fine. Of course, it consumes extra fuel, roughly half a liter more every 10 minutes, which is noticeable on my fuel gauge. But mechanically, there’s no major issue—my car’s cooling system and battery can handle it. I’d suggest not running it too long; 15 minutes is fine, and opening windows can save money. If you turn off the engine and only use the fan, it might drain the battery and cause starting issues, so keeping the engine running is safer. Overall, comfort comes first, but use it wisely to avoid wasting fuel.