Should the AC be turned on when using the heater?

[LeGiselle]

There is no need to turn on the AC when using the heater, because the AC button is only the cooling switch for the car's air conditioning. When the air conditioning is turned on, pressing this button activates the air conditioning compressor, which then blows cold air. Therefore, the AC button should not be pressed when using the heater. The correct way to use the heater is to first warm up the engine, wait for the engine's water temperature to rise, and then turn on the heater. At the same time, set the air conditioning to external circulation, wait for 3 minutes to expel the cold air inside the car, and then switch to internal circulation. This can quickly increase the temperature inside the car. The car air conditioning is used to adjust and control the temperature, humidity, air cleanliness, and air flow inside the car cabin to a suitable state.