Facing hazy windscreens during monsoon; How to get rid of it?

My friends with Creta, Ertiga and Innova are also reporting the same.

BHPian 2000rpm recently shared this with other enthusiasts.

Guys,

Me and a lot of my friends with cars of multiple manufacturers and vintage are facing a unique issue in the Mumbai Rains.

The windshield during rain always seems to be hazy. Even while using the wiper, the windshield doesn't seem to become clear. (Check video attached).

Things I have tried:

1. Wiper usage, Normal AC usage with AC blower on passengers - Doesn't clear the window.
2. Wiper usage, AC on max with the blower on windshield - doesn't clear the window.
3. Wiper usage, AC on the Heater and blower on the windshield (the windows clear up when heated but the car becomes undriveable, especially since we can't open the windows.)
4. Wiper usage with washer fluid, Normal AC usage with AC blower on passengers - doesn't clear the window.

My friends with Creta, Ertiga and Innova are also reporting the same.

Can our experienced Mumbai Veterans please help?

Here's what BHPian Jeroen had to say on the matter:

You seem to mixing problems on the inside and the outside of the window.

First, you need to check where the haze is. If is it inside, then it is a wiper problem. Difficult to see on the video, but I think the wiper is definitely leaving some haze.

Irrespective, it is always a good idea to clean the in- and outside of the windshield regularly with a proper cleaning agent. It could be just a simple household fluid, e.g. some vinegar in warm water. Or use some of the spray-on cans.

Using the window wiper washers won't really clean the glass properly.

I use special car glass polish stuff and a special car glass wipe, which I have found to make a huge difference.

Old wipers can leave smears and haze too.

Haze/condensation on the inside is usually a problem with the ventilation system. Check as Bsilver suggested the recirculation. Check you are getting sufficient airflow from the various vents, especially the ones at the front of the dash near the edge of the windshield. Without sufficient airflow, nothing is gonna happen. It might be an indication of a clogged-up cabin filter (if installed) or a stuck ventilation valve.

But again, I emphasise the need for squeaky clean windows on the inside too. If the car is smoked in, you're in for it. Almost impossible to keep the windows from getting steamed up, and haze.

So my advice, check in versus outside problems. But start with a proper cleaning in and outside.

Here's what BHPian alpha1 had to say on the matter:

1. You need to add soap/shampoo to your washer fluid. Also while cleaning the glass areas - place special importance on using soapy fluid to clean and don't RINSE off with plain water.

This is important because you need to understand what haze/fog on the glass is: it is millions of tiny, condensed droplets on the glass. This makes it optically equivalent to a glass surface with a million tiny, bumps making it opaque.

Soap/shampoo reduces surface tension, in less fancy words that means it doesn't allow water to form spherical droplets when it condenses. In fact, all the tiny droplets will merge with each other forming a thin, flat, water surface through which one can easily see across.

2. You need to keep the AC temperature as high as comfortably possible but do ensure that the AC compressor is running all the time. (In some cars, the AC may cut off at higher temperatures). Also preferably DO NOT direct the AC draft onto any glass surface.

To understand why, you need to understand that fog = tiny droplet condensation. This happens on any surface that is cold but is exposed to moist air (e.g. a tumbler with cold water/ice).

First, this happens on the inside surface. The rainy weather has already cooled the glass surface on the inside as well as outside. The introduction of breathing human beings inside the car suddenly increases moisture. This starts condensing on the inside surface. After the AC has had its proper run (say 2-5 minutes), it has removed sufficient moisture, and the fog will vanish from the inside surface.

Now because the AC continues cooling, the temperature may fall lower than the outside temperature (that's why I asked you to keep it as high as possible). In such a situation, the outside surface of the glass starts dropping, and this invites condensation and haze on the outside surface.

This is aggravated when you direct the AC draft onto the glass surface (therefore I asked not to point the vents at the glass).

Now from the video, it is not clear, but could you further elaborate if you have haze issues on the inside surface of the glass or the outside surface? (It appears to be on the outside)

Here's what BHPian Kosfactor had to say on the matter:

Weather is very humid and if the temperature drops outside, then your vehicle`s windshield is a good place for water vapor to condense.

Spray a glass cleaner generously on the windshield and run the wiper, you may have to do this every day if the route you travel has plenty of standing water on the road, there will be oil residues that would reach your windshield, causing smearing in the night.

Just use the wiper to clear the condensation and you should be good. In our cities it's not that easy to use outside air mode \ heater etc due to smoke and other fragrances from outside, so heating up the windshield may not always be possible.

Check out BHPian comments for more insights and information.