Should the AC Button Be Turned On for Hill Starts?

[DiMason]

It is not necessary to turn on the AC button for hill starts. Moreover, for some small cars with weaker power, turning on the AC during a hill start can have a noticeable impact on the vehicle's performance. Additional details are as follows: 1. The AC button in a car's air conditioning system is the cooling switch: Pressing the AC button activates the car's air conditioning to cool. The car's air conditioning is a crucial comfort feature, capable of both cooling and heating. When cooling, the compressor clutch engages, allowing the engine to drive the compressor. The compressor continuously compresses the refrigerant and delivers it to the evaporator. Inside the evaporator, the refrigerant expands and absorbs heat, thereby cooling the evaporator. The cooled evaporator then cools the air blown by the blower, allowing the car's air vents to emit cold air. 2. The refrigerant used in car air conditioning is R134a: The car's air conditioning system requires periodic refrigerant replenishment. If refrigerant is not added for a long time, it can lead to reduced cooling efficiency and slower cooling speeds. Therefore, it is essential to regularly replenish the refrigerant during routine vehicle use. When the car's air conditioning is heating, the high-temperature antifreeze from the engine flows through the heater core, and the air blown by the blower may also pass through the heater core, allowing the car's air vents to emit warm air. The heating function of the car's air conditioning relies on the engine's heat.