Should You Use Recirculation Mode When Turning on AC in Summer?
2 Answers
When using the car's air conditioning in summer, activating the recirculation mode can achieve better cooling effects. The cooling process involves lowering the temperature of hot air through the compressor before circulating it into the car. If recirculation mode is on, the already relatively cool air inside the car is further cooled down. In contrast, the fresh air mode requires cooling the hot air from outside each time, which has limited cooling efficiency per cycle. Therefore, it's evident that recirculation mode provides superior cooling performance. The differences between car recirculation and fresh air modes are as follows: 1. Different air circulation methods: Recirculation mode circulates the air inside the car in a closed loop, while fresh air mode draws outside air into the car. 2. Different air circulation states: In recirculation mode, the interior air is reheated or recooled before being sent back into the cabin. Fresh air mode heats or cools outside air before introducing it into the car. 3. Different working principles: Recirculation mode promotes air circulation within the car. Fresh air mode uses a fan to bring outside air into the vehicle while expelling interior air through another fan, achieving ventilation without opening windows.
When I first studied car air conditioning, I also struggled with this issue. To cool down quickly after being exposed to the sun, you need to turn on the internal circulation! Here's what I do every time: right after starting the car, I immediately turn on the AC and internal circulation. The cold air circulates directly inside the cabin, which is much more effective than drawing in hot air. After driving for half an hour, I switch to external circulation to ventilate, as high concentrations of carbon dioxide from exhaling can make you drowsy. You need to be even more careful on rainy days—keeping the internal circulation on when the windshield fogs up actually slows down defogging. The most intuitive way is to look at the dashboard button lights—a red light means internal circulation is on, and a green light means external circulation is on. When the red light is on, the cooling efficiency is at its highest.
