Can You Get Poisoned by Running the Car Air Conditioner While Parked?
2 Answers
Running the air conditioner while the car is parked can lead to carbon monoxide poisoning. The principles of using the car's heating and cooling system and their impact on fuel consumption are as follows: 1. Using the air conditioner while idling: This only increases fuel consumption, with significant differences in fuel usage between cooling and heating modes. 2. Fuel consumption for heating: The heating system relies on the engine's operation to heat the coolant, which then heats the heater core. The blower then sends natural air through the heated core into the car. Strictly speaking, car heating is a form of waste heat utilization and does not add any extra energy consumption—it only involves the normal idling fuel consumption. 3. Fuel consumption for cooling: The cooling system relies on the engine to drive the compressor. The compressor pushes the refrigerant through the condenser, dryer, expansion valve, and evaporator, causing the refrigerant to change between liquid and gaseous states. The cooling effect is achieved by the evaporation process lowering the temperature of the evaporator, after which the blower sends cooled air into the car. Cooling requires an additional compressor compared to heating, and since the compressor has a high power demand and is driven by the engine, using the cooling system while idling results in higher fuel consumption. A fixed-displacement compressor increases fuel consumption by about 1L/h compared to normal idling, while a variable-displacement compressor increases fuel consumption by approximately 0.5L/h after the temperature is set.
A few days ago, a friend told me a scary story about a driver who fell asleep in a garage with the air conditioning on and never woke up. In fact, carbon monoxide poisoning from idling with the AC running is a real risk! When a car idles in place, incomplete combustion of gasoline produces carbon monoxide, which is heavier than air and can seep into the cabin through gaps like the trunk. The scariest part is that it's colorless and odorless—by the time you feel dizzy or nauseous, it's often too late. So never do this in an enclosed garage, and even outdoors, avoid exceeding 20 minutes. I once encountered a car during repairs that had an exhaust leak during an inspection—such vehicles are especially dangerous with the AC on. If you must rest with the AC running, remember to crack the sunroof for ventilation to stay safe.
