Why Can Sleeping in a Car with the Air Conditioner On Be Deadly?

[AxelFitz]

Sleeping in a car with the air conditioner on can lead to carbon monoxide poisoning. Below is an introduction to car air conditioning systems: 1. Introduction to Car Air Conditioning: A car air conditioning system consists of a compressor, condenser, throttle element, evaporator, fan, and necessary control components. It is used to regulate the temperature and humidity inside the car, providing a comfortable environment for the driver. 2. Working Principle: When the compressor operates, it sucks in low-temperature, low-pressure gaseous refrigerant from the evaporator. After compression, the temperature and pressure of the refrigerant increase, and it is sent to the condenser. Inside the condenser, the high-temperature, high-pressure gaseous refrigerant transfers heat to the outside air passing through the condenser and liquefies, turning into a liquid. When the liquid refrigerant flows through the throttle device, its temperature and pressure decrease, and it enters the evaporator. Inside the evaporator, the low-temperature, low-pressure liquid refrigerant absorbs heat from the air inside the car passing through the evaporator and evaporates, turning into a gas. The gas is then sucked back into the compressor to start the next cycle.

[StEllie]

I've been driving for over 30 years and heard many tragic stories. The main reason people die from sleeping in cars with AC on is carbon monoxide poisoning. When the engine runs, the exhaust pipe emits this gas – colorless, odorless, but deadly. If the car is tightly sealed or the AC is set to recirculate, CO gas gradually seeps into the cabin. At high concentrations, it causes unconsciousness or fatal suffocation. I remember a friend in the 2000s who rested in a garage with the engine and AC running – when found, it was too late. Now I always warn people: never sleep too long in a running car, especially at night or in enclosed spaces. For safety, either turn off the engine and open windows, or park in ventilated areas using fresh air mode. Regular exhaust system checks also reduce risks.

[Faunus]

As an enthusiast who often ponders about cars, the main reason for fatal incidents when sleeping with the air conditioning on is carbon monoxide leakage. The exhaust system at the rear of the car is designed to expel waste gases, but if you're in an enclosed space like a garage or under shade, these gases can flow back into the car. Coupled with the air conditioning's recirculation mode, it becomes easier for CO to accumulate. Once inhaled, CO displaces oxygen, causing dizziness or even fatal consequences. I recommend always using the fresh air mode or resting with the air conditioning on in open areas. Additionally, older cars or those with faulty exhaust pipes pose higher risks, so timely maintenance is crucial. It's best to avoid this practice altogether. If absolutely necessary, crack the window open for a short while to ensure air quality and safety.

[SanDaniela]

As a parent of two kids, I'm particularly concerned about this risk. Sleeping in a car with the air conditioning on can be fatal due to carbon monoxide poisoning. The gas is emitted from the engine and accumulates in the enclosed cabin, which is then inhaled into the lungs, causing rapid unconsciousness and suffocation. Many cases involve parents who, after getting tired from playing with their kids, fall asleep in the car, leading to tragic outcomes. Safety first—I never let my children sleep in a running car. If they really need to rest, I turn off the engine and open the windows for ventilation. Checking the car's condition is also crucial, such as ensuring the exhaust pipe isn't leaking or blocked. Regular maintenance can prevent accidents. Protecting yourself and your family is vital—even small precautions can save lives.