Should the AC be turned on for car heating in winter?
2 Answers
In winter, you don't need to turn on the AC when using the car's heating system. Pressing the AC button activates the compressor, which provides cold air, while the heating system doesn't require it. This is because the heating system transfers part of the heat originally dissipated through the radiator into the cabin. Therefore, using cold air will offset some of the engine's power, whereas heating won't affect the power. Here is some information about the AC: 1. The AC button starts the compressor, which pressurizes the refrigerant (Freon). To use the heating, you don't need to turn on the AC; simply adjust the air volume button to blow warm air. The warm air at this time utilizes the car's internal heat cycle, transferring the heat dissipated through the radiator into the cabin without increasing fuel consumption. The heating needs to be preheated; when the car is just started, the coolant temperature is low, and it takes some time for the blower to deliver warm air. 2. The AC is the cooling button, which is the most energy-consuming and fuel-intensive function of the air conditioning system. The heating function of the air conditioner doesn't require 'cooling' at all; the car can fully operate the air conditioning using the heat generated by the engine.
Should you turn on the AC when using the heater in winter? I think the key is the anti-fogging effect. In winter, the car interior tends to fog up, especially after rain or snow, when the windshield suddenly becomes misty, making driving particularly dangerous. I've always made it a habit to press the AC button while using the heater in winter because it helps dehumidify and defog, clearing the view faster. Cars with automatic air conditioning are more convenient—just press the AUTO button, and the system adjusts whether the AC is on or off. If you only blow hot air without the AC, the moisture can't be expelled, and fogging will recur. If visibility suddenly drops on the highway, the consequences could be severe. I usually check the cabin air filter more often to keep it clean for better performance. Overall, safety comes first—turn on the AC when needed, and don't skimp on this.
