What is the car heating symbol?

[LylaLee]

Some cars use a red zone to represent heating, where turning the knob gradually increases the temperature in the red area. Other cars use a "small sun" symbol to indicate heating. The methods and precautions for using the heating system are as follows: How to use the heating system: Adjust the air vents to the front windshield, turn on the air conditioning cooling, and activate the external circulation mode. Using the maximum fan speed, it usually takes only about ten seconds to quickly remove fog from the glass. Precautions for using the heating system: Do not turn on the heating immediately after starting a cold engine in winter. This not only fails to provide warmth but also increases the engine's burden because the water temperature has not yet risen when the car is just started. First, warm up the engine and simultaneously turn on the external circulation mode. If the heating system is used for a long time, it is necessary to ventilate the car appropriately. You can open the window slightly to maintain air circulation inside and outside the car. Relying solely on external circulation is not enough; you must open the window.