Best routine for making a frozen car driveable

Question

With temperatures below zero it's always difficult to get going even if the engine itself starts without hiccups and I'd like to know what to do better so that I don't need to wait ten minutes before the car is somewhat safe to drive.

It takes ten to fifteen minutes before the car is driveable in winter. I follow my father's routine of starting the car, opening front doors or windows at least a bit, cranking up the air blower to full power for windshield (with AC on), than get out and scrape off ice from windshield and windows.

After this, it takes about ten to fifteen minutes, before I can drive safely - actually see through the windscreen and windows. It seems as though a new thin layer of ice forms on my windshield and without the blower set to full, condensation from my breath forms ice buildup on the inside as well. Having front windows open helps a bit the icing problem at the price of freezing me some more. The problem is made wors when there is any light source directed at the windshield (sun, street lamps, other cars), because otherwise transparent winshield becomes somewhat opaque. Applying windshield washer is no option, since the liquid available here is non-freeze for storage only and freezes as soon as it hits the frozen glass.

Other problems are that the user manual of the car strongly advises to get going right after starting the engine (as opposed to leaving the car to heat up, as was usual in the olden days), and I hear that local laws actually forbit leaving a car idling (you don't get actually fined, but I don't want to set ground for neigborhood complaints).

Usual temperature in my location doesn't fall below -10 °C, I have a 10 year old diesel car without dedicated electrical windshield heater or electrical air heater (only engine coolant heating).

Is there something I can do to shorten the time needed to get the car to safe-to-drive state?

Answer 1

Get an insulating blanket for at least your windshield. You place this over the windshield at night, and it prevents frost from forming. The windscreen is the most difficult to get ice-free, so this usually reduces the time to get the car ice-free by half. These can be bought in auto supply shops.

There are also blankets that go over all windows.

Edit: There is one thing to keep in mind when you use a blanket. Don't use one when it rains and then freezes (e.g. temperature just above freezing during the day, and below freezing at night). Dry snow is okay, but when rain gets between the blanket and windshield and then freezes up, you have to start the car and wait until it warms up enough to defrost the entire windshield, and that takes a long time.

Having the engine running while you're out scraping the windows is only necessary in extreme weather. A diesel will take a very long time to warm up when it's idling at no load, so you usually finish scraping before the air gets noticeably warm. It's better to scrape first, then start the engine and drive off (better for the engine, which will reach operating temperature faster, and better for the neighbours).

You indicate that you can't get windscreen washing fluid with antifreeze in it, otherwise that would be an option. In my country I can get spray bottles with antifreeze agent. When I spray that on the frosted-over window, it becomes much easier to remove the ice. It's still not as good as using a blanket though.

If cost is no object, there are heaters you can install in your car, these run either on petrol/diesel or electric power. The petrol/diesel versions are spliced into the engine coolant circuit and can heat up both the engine and the interior of the car. The electric versions are usually only for heating up the engine oil (and are popular in countries with real winters).

If you can, park your car as close as possible to a building. I live in an apartment building, and when I park the car next to it, the car windows don't freeze until it's -5 °C. The car's sheltered from the wind, and the air just outside the building is heated up by the heat leaking from the apartments.

Answer 2

Most diesel engines have block heaters for cold weather starting. This helps ease of starting, but also keeps the coolant at a higher than ambient temperature which helps reduce time to warm the interior of the car. If your car does not have one, it is something that can be added.

In cold weather conditions it is also important to have the interior of the windows clean. Dirty windows tend to fog or glaze over easily. Also, make sure you are using fresh air to the cabin during heating. Not recirculating which can also cause fogging and make it difficult to keep the windshield clear.

Answer 3

Ensure that your washer fluid is filled with appropriate temperature rated screen wash so that it does not freeze.

What I find helps is to decant a small amount of this screenwash into a Trigger Spray Bottle / Mister Trigger Bottle and keep it handy. Instead of trying to scrape the ice from the outside of the windows, mist it with a liberal spray from this bottle. This softens the ice considerably which significantly reduces the amount of scraping required.

Another trick is to, when the vehicle is warm, thoroughly clean the inside of the windscreen and finish by wiping the inside of the glass down with old news paper. This removes deposits from the glass which can mist up (when you subsequently breathe on it when it is cold).

One final tip is to try and absorb as much condensation from the inside of the car as possible. I have an old sock filled with silicone cat litter in the car which I position on the top of the dashboard overnight. This has almost completely removed the need to demist the inside of the glass as it traps moisture which otherwise would attach itself to the inside of the glass.

Answer 4

I do pretty much what you do, but I also make sure that I am pulling in fresh air from the outside and not recirculating air, which seems to help a lot with regards to mist & condensation forming inside the windshield. My guess is that my breath, and snow or ice on your shoes melting next to where the recirculation in-duct is, both increase internal humidity and make the cold windshield fog up more easily.