Do You Need to Turn on AC in Car Air Conditioning During Winter?

[DiJames]

You do not need to turn on AC in car air conditioning during winter. The reason why the car air conditioner does not use the compressor for heating is that the heat generated by the engine operation is absorbed by the coolant outside the cylinder. The heated coolant then flows to the heat exchanger, where the heat carried by the coolant is released, heating the cold air entering the car. This heated air is then sent into the car to provide warmth. The only time you need to use AC when using the heater is to defog the windows. In winter, the ambient temperature is low, and it is common to close all windows and turn on the internal circulation while driving. The downside is that the humidity inside the car will increase, leading to fogging on the windows. Turning on AC will quickly remove the fog.