Can I Keep the Air Conditioner Running While Parked?
3 Answers
It has an impact on the car. In the long run: It can easily damage the engine. And it is expensive. Essentially: Car air conditioners and ordinary household air conditioners use the heat pump principle, adjusting the air temperature inside the car based on changes in the refrigerant state and the conversion of latent and sensible heat. The working process is (starting from the compressor inlet): Low-temperature and low-pressure gas enters the compressor: Because the volume decreases, the pressure increases, the temperature rises, turning it into high-temperature and high-pressure gas. High-temperature and high-pressure gas enters the condenser: The condenser is a highly efficient heat exchanger that can use external air to heat the refrigerant and convert it into high-temperature and high-pressure liquid. High-temperature and high-pressure liquid passes through the expansion valve: Through the action of the throttle expansion valve, it is converted into low-temperature and low-pressure atomized liquid. Low-temperature and low-pressure liquid enters the evaporator: The evaporator has a similar structure to the condenser, but at this time, due to low pressure and low boiling point, it will absorb heat from the external air and evaporate into low-pressure and low-temperature gas.
This is something that really needs to be discussed carefully. Last time I parked and slept with the AC on, it almost caused an accident! When idling with the AC on, gasoline cars produce large amounts of carbon monoxide. If the garage or underground parking lot isn’t well-ventilated, levels can exceed safety limits in just half an hour, leading to poisoning. Even with the windows slightly open, exhaust fumes can easily seep in when the car isn’t moving. A friend of mine was waiting for their child after class with the heater on and fell asleep—they woke up dizzy and nauseous and had to be rushed to the hospital. With new energy vehicles, you don’t have to worry about exhaust fumes when running the AC, but the battery can’t last all night. Suddenly losing power in the middle of the night means waking up either scorching in summer or freezing in winter—which is even worse.
As a veteran taxi driver with 15 years of experience, I recommend not idling with the AC on for more than 20 minutes. Prolonged low-speed engine operation not only leads to carbon buildup but also consumes terrifying amounts of fuel. My old car was tested - idling with AC for one hour burns nearly 2 liters of gas, enough to drive 20-30 kilometers. Plus, the radiator cooling fan works overtime. I've personally seen several cars' radiators boil over with white smoke during summer traffic jams. If you really need to wait, it's better to turn off the engine and rest in the shade. If it's unbearably hot, start the engine for 10 minutes of cooling before shutting it off again.
