How common is this scenario? You come out to your car on a cold winter’s morning, and find that it is covered in frost. So you clear the outside of your car windows – using possibly the labour-intensive method of a plastic scraper, or the lazy person’s way, by either spraying on a proprietary de-icing fluid, or pouring warm water over it to melt the ice.
You then get into your car – and promptly find that insides of the car windows, too, are covered in a layer of ice. What do you next?
Inside AND Out
The answer is certainly not drive off immediately, hoping that your car’s internal heating or air conditioning system will soon kick in, and demist the windows for you.
The misting up of the interior surfaces of a car in cold weather is due to their rapid heating up when you climb into your car, and the sudden difference in humidity between the cold outside and the rapidly warming-up interior. This causes condensation, and requires certain steps in order to clear it, not to mention a little time.
The quickest way of dealing with this is to try to equalise the temperature inside and outside the vehicle as quickly as possible. Winding down the windows will help, but more effective is to turn the vehicle’s ventilation fan on to maximum power, while turning the temperature control down to its lowest setting.
But this isn’t very comfortable for the occupants of the vehicle. So the easiest way of clearing a fogged windscreen is – if you’re lucky enough to have it fitted in your car – use its air-conditioning system.
Air conditioning + engine heat = a quicker clearing screen
The advantage of having an air conditioning system in your car is principally that it cools incoming warm air by passing it through the car’s cooling system. Yet on cold mornings, it effectively works in reverse.
Condensation on the inside of the car’s windows means that the freezing air from outside the car has met the slightly warmer air inside the car, and this in turn has collected on your windows, and caused them to mist up.
So to dissipate the heat which has arrived in the car – chiefly via your and your passengers’ no doubt well wrapped-up bodies – you need to mitigate the effects of that sudden change of temperature.
You can do this by switching on your car’s air conditioning, and turning the fan up to maximum. Again, this might lead to some temporary discomfort for you and your passengers, but it is likely to be a quicker and more effective way of clearing your windows than wiping them with your hands or a cloth, and smearing them.
It works as a dehumidifier, and when used in conjunction with the heater, clears away condensation reasonably quickly.
Clean car windows at all times save time
Everyone is always busy, and it can be a a struggle to find time to keep your car clean. However, if your car windows are covered in grease or are streaky as a result of not having been cleaned for a while, then the air conditioning will have to work that much harder to clear the glass. So in winter in particular, try to always keep your windscreen clean on the inside, as you’ll then have to spend less time dealing with the effects of colder weather. And rather than using your own energy, you can let the power of the car’s heating and cooling system do the hard work for you.