There are two conditions for window fog
High humidity
In the case of a certain air humidity, when the window temperature is lower than the dew point temperature, dew will form on the window surface, which is the phenomenon that we often see in the front windshield fog.
Too low temperature
There is a certain temperature difference on both sides of the window, and when the saturated steam of the surface water with low temperature is lower than the steam pressure of the surrounding environment, the water vapor accumulates on the surface of the glass and forms fog steam in the form of tiny water droplets.
If the dew point temperature is higher than zero degrees Celsius, fog formation phenomenon; If the dew point temperature is below zero degrees Celsius, it becomes frost.
Ways to avoid window fog:
1. Use the car air conditioning system.
The most common way is to open the fan and the cooling switch in the car, and the cold air will blow to the windshield and quickly “sweep away the fog.” The effect of this move is very quick and direct, but the biggest drawback also follows, that is, the car will feel cold. In fact, in addition to air conditioning refrigeration in addition to fog, the use of hot air can also play a role in removing fog.
The operation method is to park the car, start the air conditioner, turn the temperature adjustment button of the air conditioner to the direction of the hot air, and then select the fog control, and dry the fog with the hot air. In addition to fog, the air conditioning can be converted to an external cycle, so that fresh air outside the cab. The initial effect of this method is general, and when it is just opened, it will even make the fog inside the glass become larger, because the temperature difference between the inside and outside is larger, but it can cure the root cause, and the water vapor in the car can be dried after a few minutes, and the fog will not be repeated, and the temperature in the car is more pleasant.
In addition to the front windshield, the side Windows will also fog, and the fog on the front side window will affect the driver’s view of the rearview mirror. Today’s cars have a separate blow to the front side window of the small air outlet, if you want to make the side window more obvious fog effect, it is best to close the two central air outlet, so that the two sides of the air outlet to obtain greater air volume to blow the fog.
2. Open Windows to allow convection of hot and cold air.
If the fog is not large and the outside of the car is not very cold, the Windows on both sides can be opened a gap, so that the air in the car is convection, the temperature in the car is slowly close to the temperature outside the car, and the fog will disperse. This is a simple and convenient method in the case of no rain and the temperature outside the car is not very low, the disadvantage is that it is not suitable for use when running at high speed.
3. Use special anti-fog products.
Such products are available at auto supply stores and online. Spray and wipe evenly on the window before each use to form a transparent protective film on the glass to prevent the formation of fog. Spray once can prevent fog for ten days to half a month, the disadvantage is that the cost is higher.
4. Wash with dry cloth.
Mix dishwashing liquid with water (the ratio is 1:6), apply evenly on the glass of the car with a sponge, and wipe it off with a towel after drying, leaving no watermark. Under normal circumstances, it can effectively maintain no fog within 20 hours. Its principle is basically the same as spraying special antifogging agent, but the effect is slightly worse, which is a simple and economical method.
5. Don’t forget the rear windshield heating wire.
At present, the models sold on the market basically have the “rear windshield heating” function, and the instructions of the switch button are much the same. Turn on the “rear windshield heat” switch, and you can make the rear window bright in less than a minute.
