What to Do When Fogging Occurs with AC On?

[OAlaina]

Generally, the front windshield defrosting function is used to treat the front windshield based on the driving environment. It is recommended to direct airflow to the front windshield and central vents, and activate the rear windshield heating function. Activate both the front windshield defrosting and rear windshield heating functions. If fogging occurs on the side windows, slightly opening them at an angle can help.

[CharlotteLynn]

Turning on the AC often causes fogging, a common issue mainly due to low interior temperature, high exterior humidity, and condensation on the windows. The solution is simple: avoid using recirculation mode continuously when the AC is on—switch to fresh air intake instead; increase the fan speed or avoid setting the temperature too low; press the defrost button and direct airflow to the windshield to quickly clear the fog. If heavy fog severely obstructs visibility, pull over to address it—safety first. Additionally, clean the AC vents, as dust buildup can block airflow and worsen fogging. Remember to maintain the AC system regularly and start cooling early in summer to prevent moisture buildup. Though fogging seems minor, obscured vision while driving is dangerous—adjust promptly and don’t cut corners.

[JulietteDella]

To deal with air conditioning fogging, here are some quick tips: When turning on the AC, immediately switch to the external circulation mode to avoid stuffy air inside the car; turn the fan up a notch and increase the temperature by a degree or two; press the defrost button or adjust the air vent to the front windshield. If that doesn't work, briefly open the window to let out the warm air. After the fog clears, don't turn off the AC too soon—keep the air circulating. Keeping an anti-fog spray in the car for quick fixes is also helpful. When driving normally, avoid using overly cold air in humid weather, and replace the AC filter annually to prevent moisture buildup. These small tricks are effective, ensuring clear visibility and safe driving.

[McElias]

It's quite troublesome when fog appears as soon as the air conditioning is turned on, mainly due to the large temperature difference between inside and outside causing condensation on the glass. The quick solution is to immediately increase the fan speed or press the defrost button to direct airflow to the windshield; at the same time, check if the air conditioning is in recirculation mode, as switching to fresh air mode is better. If the fog obstructs visibility, pull over instead of driving blindly. To prevent air stagnation in the car, crack a window for ventilation or use fresh air mode to introduce dry air. During humid weather when using cold air for dehumidification, avoid setting the temperature too low—moderate fan strength is usually sufficient. Pay attention to the cleanliness of the air filter and ventilation ducts to reduce the risk of humidity buildup.

[MacPaul]

Turning on the AC causes fogging, which I believe is mainly due to the imbalance of humidity inside and outside the car, leading to condensation from temperature differences. Solutions: Immediately increase the fan speed to defog the windshield; ensure the AC is set to fresh air mode instead of recirculation to avoid trapping moisture; adjust the temperature slightly higher to reduce the temperature difference on cold surfaces. In the long term: park in dry areas; in summer, open the windows for a few minutes to reduce humidity before turning on the AC; regularly check and replace the cabin air filter if it's dirty or damp; keep dehumidifiers or anti-fog sprays in the car for emergencies. These small habits help prevent fogging, enhancing driving comfort and safety.