Do you know that too: Just got into the car and the windows are already fogging up. But why actually? This is due to your warm breath, which condenses on the cold window glass due to strong temperature differences. But what if the car windows are already fogged up before you get in the vehicle? The assumption here is that there is too much residual moisture in your car. In both cases, a dehumidifier is supposed to help, but what exactly is that? And how can moisture in the car be avoided or at least reduced? We’ll tell you.

A vehicle dehumidifier is a type of cushion filled with special granules or leak-proof gel. You place this in the car (e.g. on the dashboard) to pull the moisture out of the air. This should not only reduce fogged windows and bad smells, but also prevent mold, rust and mold stains. Depending on the manufacturer, the duration of action is between several weeks and up to three months – it always depends on the size of the vehicle interior. What is particularly practical about this type of dehumidifier is that it can not only be used in the car: the cushions serve the same purpose in caravans or mobile homes, in (closed) garages or even inside a boat.

And the best thing about it is that once the pillow is soaked and no longer absorbs moisture, it only needs to be dried in the microwave (or on the heater) for a few minutes – and then it’s ready for use again.

If the windows in your car fog up as soon as you drive off, the first thing you should do is turn on the fan and aim it at the windshield. It is also helpful to briefly turn the heating up to full power so that the outflowing air warms up more quickly. If, on the other hand, the windows gradually mist up while driving, this may be due to the air recirculation switch – here it is advisable to turn it off and switch on the air conditioning system (if one is available) instead. It transports the humid air from the vehicle interior directly to the outside.

In addition to the dehumidifier for cars described above, you can also use other aids to prevent fogged windows: such as an anti-fog spray for glass and plastic panes, which must be applied every one to two weeks to be effective . Alternatively, you can also use a microfibre window sponge in the vehicle – or a special anti-fog sponge. In any case, it is important that you only use clean rags or towels, as dirty windows tend to fog up faster than clean ones due to the film of dirt.

According to the ADAC, you can take a number of preventive measures to prevent moisture from collecting inside the vehicle and promoting fogged windows and mold:

Sources: ADAC, Autobild

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