Can You Turn on the Air Conditioning When the Car is Powered but Not Started?
3 Answers
You cannot turn on the air conditioning when the car is not started, because the operation of the car air conditioning's cooling compressor relies on the engine running, and the energy for warm air (hot water) is generated by the engine heating up. Hazards of turning on the air conditioning without starting the car: If the air conditioning is turned on for a long time without starting the car, the car battery will be depleted. In mild cases, the car may not start, and in severe cases, it can cause the battery to remain in a state of undercharge for a long time. However, this does not occur in new energy vehicles. Not turning off the air conditioning after the car is turned off has a significant impact on the car. Function of the car air conditioning system: It is designed to cool, heat, ventilate, and purify the air inside the car. It provides a comfortable environment for passengers, reduces driver fatigue, and improves driving safety. The air conditioning system has become one of the indicators of whether a car is fully equipped. It generally includes a cooling device, a heating device, and a ventilation device. This combined system makes full use of the limited space inside the car, has a simple structure, and is easy to operate, making it a popular modern car air conditioning system internationally.
I've tried this operation before while waiting for a friend in the garage. In the state where the car is powered on but not started, the air conditioning blower function can actually be used, but there are several key points to note. The compressor won't activate in this state, so you can't get cold air - only natural airflow. However, the blower motor runs on battery power, and keeping it on for extended periods will drain the battery. Once when I was waiting in the car with the blower on, the car struggled to start after half an hour. In winter, the heating system also requires the engine to be running so the coolant can warm up and provide heat. It's recommended to limit ventilation to 15 minutes max in this situation. If you need it for longer periods, it's safer to start the engine, otherwise you might end up stranded with a dead battery.
I remember last summer when I took my child to extracurricular classes, I tried turning on the air conditioning in the parking lot with just the electrical power on. The blower indeed blew air, but pressing the AC button produced no cold air at all. Later, the mechanic told me that this is like plugging a phone into a charger without turning on the power. The compressor doesn't work unless the engine is running, and only the electric blower is consuming the battery's power. The battery can probably last only half an hour to an hour, and it would be a big loss if you couldn't start the car because of this. The heater also requires the engine's heat, so there's no warmth with just the electrical power on. You can use it for short-term ventilation in emergencies, but for prolonged use, you need to start the vehicle.
