Should the AC be turned on when using the car's air conditioning?
3 Answers
To use the cold air function, you must press the AC button; otherwise, the air conditioning system will only blow air at normal temperature. This is because the AC button controls the compressor, a key component of the cooling system. When using the cold air function, try to avoid prolonged use. Keeping the air conditioning at a low temperature for too long can create a significant temperature difference between the inside and outside of the car and increase fuel consumption. The car's air conditioning cooling system consists of a compressor, condenser, receiver-drier, expansion valve, evaporator, and blower. These components are connected by copper (or aluminum) pipes and high-pressure rubber hoses to form a sealed system. When the cooling system operates, the refrigerant circulates through this sealed system in different states, achieving the purpose of lowering the temperature of the air around the evaporator. Compression process: The compressor draws in low-temperature, low-pressure refrigerant gas from the evaporator outlet and compresses it into high-temperature, high-pressure gas, which is then discharged from the compressor. Heat dissipation process: The high-temperature, high-pressure superheated refrigerant gas enters the condenser. Due to the drop in pressure and temperature, the refrigerant gas condenses into a liquid, releasing a large amount of heat. Throttling process: The higher-temperature and higher-pressure refrigerant liquid passes through the expansion device, where its volume increases, and its pressure and temperature drop sharply, exiting the expansion device as a mist (fine droplets). Heat absorption process: The mist-like refrigerant liquid enters the evaporator. Since the boiling point of the refrigerant is much lower than the temperature inside the evaporator, the refrigerant liquid evaporates into a gas. During this process, it absorbs a large amount of heat from the surroundings, and the low-temperature, low-pressure refrigerant vapor then re-enters the compressor. Precautions for using the air conditioning in the car: Do not set the air conditioning temperature too low. A large temperature difference between the inside and outside of the car can easily cause the driver to catch a cold, and excessively low temperatures may also increase the risk of arthritis for passengers. Control the direction of the air vents. Based on the principle that cold air sinks and hot air rises, when using the air conditioning, set the vents to face upward when cooling and downward when heating. Do not turn on the air conditioning immediately after the car has been exposed to the sun. After prolonged exposure, the temperature inside the car will be very high. First, open the windows to ventilate and allow the hot air to escape before turning on the air conditioning.
When I first bought my car, I didn’t really understand whether to turn on the AC when using the cooling system. After trying a few times, I realized that without the AC, the fan alone couldn’t blow cold air—the car remained just as stuffy and hot. The AC switch controls the compressor for cooling; you must turn it on to lower the temperature. Otherwise, the fan just blows in hot air from outside, making it feel like driving in an oven. I remember one summer business trip when I forgot to turn on the AC, and my clothes were soaked with sweat, which really distracted me while driving. Since then, I’ve made it a habit to check if the AC light is on. Using the AC also helps defog the windows, which is especially useful on rainy days to avoid obscured visibility. I’d recommend friends regularly clean the AC filter to prevent clogging, as a dirty filter can reduce cooling efficiency and waste fuel. A more comfortable drive means a better mood and safer driving.
As someone who frequently goes on road trips, I know very well that turning on the AC is necessary for cool air. The AC is the switch for the air conditioning compressor, and without it, the car will only blow natural air, which isn't refreshing. The compressor cools hot air into cold air, and in summer, not turning on the AC can cause the car's interior temperature to soar to 40 degrees, making people drowsy and creating a dangerous situation. I've found that after starting the car, opening the windows first to let out the hot air before turning on the AC and switching to recirculation mode cools the car faster, making the AC more efficient and saving fuel. It's also important to maintain the AC system regularly, such as changing the filter annually to prevent dust buildup from affecting performance. In short, if you want cool air, don't be lazy—press the AC button for a more comfortable and enduring drive.
