What to Do When Fogging Occurs with Air Conditioning in Summer?

[OWillow]

While driving, you can slightly open the windows to ensure air circulation inside the car, balancing the interior temperature with the outside temperature. In case of window fogging, you can apply a defogging spray to eliminate the fog on the glass. Spray a small amount of defogging agent onto the car window and then wipe it clean. Alternatively, you can use soapy water, dishwashing liquid, or alcohol as substitutes for defogging agents. These can prevent fogging on the car windows for several days and also help remove existing fog.

[AndresLynn]

I've got quite some experience dealing with fogging up when using AC in summer. It mainly happens because of the big temperature difference between hot outside and cold inside, plus high humidity, which causes condensation on the inner side of the windshield. My usual approach is to first open the windows for ventilation to reduce the temperature difference, then turn on the AC without setting it too low, direct the vents towards the windshield, and press the front defogger button with higher fan speed to quickly remove moisture with cold air. Also, remember to use the external air circulation to bring in dry air, and switch to internal circulation only after the fog clears. Additionally, I keep an anti-fog spray in my car and apply it to the glass periodically to effectively reduce fogging. Another handy tip is to use diluted soapy water to wipe the glass, which is economical and practical.

[McIker]

Solving the issue of air conditioning fogging is actually not difficult. I usually start by turning on the external circulation as soon as I get in the car, while setting the air conditioning temperature to around 20-24 degrees Celsius with the fan speed at maximum. Adjust the air vent direction to blow upward toward the windshield, using the cold air from the AC to disperse the fog on the glass. During this process, it's also important to press the A/C button because the compressor not only cools but also effectively dehumidifies, which is the key to defogging. After a few minutes, when the fog has mostly cleared, reduce the fan speed for comfort. Additionally, remember to regularly clean the oily film on the inside of the front windshield, as this is often overlooked. A buildup of oily film makes fog more likely to condense. Another tip is to avoid leaving wet items in the car, as they can increase interior humidity.

[VanClara]

I have two go-to methods for defogging. First, immediately turn on the front windshield defogger with the fan at maximum speed, while ensuring the A/C is on for dehumidification. If the fogging is light, cracking the window slightly can quickly balance the temperature difference inside and out. Cold air defogs quickly but tends to recur, so I sometimes switch to warm air defogging mode—though it initially worsens the fog, the effect lasts longer once the warm, dry air circulates. Placing moisture absorbers inside the car or regularly wiping the interior glass with a dry towel also helps prevent fogging.

[AmeliaAnn]

The principle of fogging in air conditioning is quite simple—it's caused by a large temperature difference between the inside and outside of the car combined with high humidity. My approach is to first turn on the A/C, which is key for dehumidification. Then, switch to external air circulation to draw in dry air, direct the airflow toward the windshield, and set the fan speed to about two-thirds to quickly form a layer of cold air on the glass surface. If the fogging is severe, it's advisable to also activate the rear windshield heating function to assist in defogging. For routine maintenance, keeping the air filter clean is crucial, as a dirty filter can reduce dehumidification efficiency. Additionally, try to park in shaded areas to avoid sudden temperature differences caused by turning on the air conditioning after the car has been exposed to intense sunlight.

[DiEmmanuel]

I usually solve fogging issues by pressing the front defrost button, but it's important to follow the correct steps: First, start the engine, then turn on the A/C switch, press the front defrost button with the fan and wave symbol, adjust the fan speed to medium-high, and maintain it for a minute or two. A special reminder: avoid directing the airflow at people immediately to prevent catching a cold. Also, check if the car windows and doors are tightly closed, as air leaks can reduce defrosting effectiveness. For prevention, I use a dedicated glass cleaner to wipe the inner windshield once a month to minimize oil film buildup. A handy life hack is to rub the glass with a potato slice—the starch film it leaves can prevent fogging. Additionally, it's best to clean the air conditioning ducts annually to prevent mold growth and excess moisture.