Should the AC be turned on when using the heater?

[IkerMarie]

There is no need to turn on the AC when using the heater. The AC button is used for air conditioning adjustment. In summer, when turning on the cold air, you can press the AC button to start the air conditioning compressor for cooling. In winter, when using the heater, there is no need to turn on this button. The AC will not operate the air conditioning compressor for heating, as the heater does not rely on the compressor for warmth. Instead, it transfers the heat from the engine to the interior of the car. Additional information: 1. Using the heater does not consume fuel: The reason the heater does not consume fuel is that it transfers the heat generated by the engine to the car's interior. Even if the heater is not used, the engine will still produce heat, which will be expelled outside the car. Therefore, there is no correlation between using the heater and fuel consumption. 2. Precautions when using the heater: Since the heat from the heater comes from the engine, prolonged use can produce toxic gases such as carbon monoxide, which can be dangerous for passengers inside the car. If you notice any unusual air quality inside the car, immediately open the windows and doors to ventilate and expel the toxic gases. Additionally, when there is frost or fog on the car windows, the heater can also be used to remove it.

[KadenDella]

I've been driving for twenty years and often encounter the question of whether to turn on the AC when using the heater. Based on experience, in damp and cold weather such as rain or fog, turning on the AC is crucial because it can dehumidify and prevent window fogging, ensuring clear visibility and safe driving. However, on dry winter days, the AC can be turned off to save fuel and reduce emissions. My approach is to observe the weather: if the humidity is high, turn on the AC along with the heater for quick dehumidification; if the air is dry, turn off the AC and just use the heater, increasing the fan speed can also prevent fogging. Additionally, I regularly check the air conditioning system to ensure the compressor and fan are working properly, preventing issues before they arise. Overall, the suggestion is to adjust flexibly based on the actual environment for both environmental friendliness and safety.

[DeCollin]

As an ordinary driver, my habit is to always turn on the AC when using the heater, especially during humid seasons. I remember one rainy day last month when I didn't turn on the AC, and the windows quickly fogged up, making it hard to see the road—I almost had a collision. Turning on the AC instantly cleared the windows, giving me peace of mind. So now, when humidity is high, I definitely use the AC for dehumidification to avoid danger. There's a slight increase in fuel consumption, but I think it's worth it—comfort and safety come first. On sunny days, I can turn it off and just enjoy the warm air to save a bit on fuel. I recommend everyone make simple adjustments based on humidity levels for a more worry-free driving experience.

[StGenevieve]

From an energy-saving perspective, I prefer using the heater without AC unless absolutely necessary. The AC consumes more fuel and increases pollution. In dry winters, simply using the heater with high fan speed to blow on the windshield can effectively prevent fogging, saving time and fuel. Only in extremely humid conditions would I briefly turn on the AC for dehumidification before promptly turning it off, as protecting the environment is paramount. This is how I balance daily needs to minimize energy waste.

[SanJoel]

As a beginner driver unfamiliar with the functions, I initially thought turning on the heater with AC would make it colder, but it's actually a dehumidifying lifesaver. Always turn it on during rainy or foggy weather to prevent dangerous fogging. After a few operations, it becomes natural with practice and learning.