Should the AC be turned on when using the car heater?

[StHarley]

It is not necessary to turn on the AC button when using the heater. Here is some relevant knowledge about the AC button: 1. Function: The AC button is used for air conditioning adjustment. It can be turned on when using the cold air to activate the air conditioning compressor for cooling. However, it is not recommended to turn on this button when using the heater, as it will not activate the air conditioning compressor for heating. 2. Principle of car heater operation: The heater utilizes the heat generated by the engine during operation. After the engine's cooling system dissipates heat from the engine, a fan directs this heat into the car's interior, creating warm air.

[LaMaddox]

When using the heater in winter, I usually don't need to turn on the AC switch because the warm air mainly comes from the engine's heat. Simply adjusting the temperature level and airflow through the climate control panel is sufficient. The AC activates the compressor for cooling and dehumidification, which consumes extra fuel—unnecessary if there's no fogging issue. However, if heavy condensation obstructs visibility, such as on rainy days or due to excessive breath fogging, turning on the AC for a few minutes to quickly dehumidify and clear the fog is both safe and effective. Afterward, turning off the AC and continuing with the heater alone is enough. I've noticed many mistakenly believe the AC makes the heater warmer, but this is purely a misconception—the heater's temperature depends on the coolant circulation system. Regular maintenance checks of antifreeze and cabin air filters ensure efficient heating, saving money and providing peace of mind. In short, warming the car is straightforward without complex switching; only use the AC as a safety aid in specific situations.

[DiValeria]

From a daily driving perspective, I usually don't need to press the AC button when turning on the heater. The warm air comes from the engine's waste heat circulation - just adjust the temperature knob and fan speed for cozy warmth. The AC is for summer cooling or dehumidifying to clear fogged windows, which activates the compressor and consumes extra fuel. If you're just heating, don't waste gas especially when fuel prices rise. However, remember to briefly turn on AC for quick defogging during poor visibility in foggy conditions before switching it off for safety. Developing the habit of distinguishing these functions makes your AC system last longer. Keeping a small towel in the car to wipe windows occasionally also helps prevent fogging effortlessly.

[VonJonathan]

From an energy-saving and eco-friendly perspective, I strongly recommend not turning on the AC. The AC compressor consumes fuel and increases emissions, which is not green. The heater utilizes free heat by directly harnessing waste heat from the engine, making it environmentally friendly, fuel-efficient, and reducing carbon footprint. Only turn on the AC when absolutely necessary, such as in extreme cold or when fog obstructs visibility to prevent accidents. This driving habit contributes to sustainable development while saving money and being considerate.