Ideal settings to reduce fog

[toolman335]

I tried searching this forum for my answer but I didn't find what I'm looking for. This is my first winter with my Model 3.

Since the temperatures dropped into the 30's a week ago, I haven't been able to find the ideal settings to both heat and get the excessive amount of fog off the windshield.
I've messed around with all types of settings and can heat the cabin without issue, but the fog issue is unreal. The only way I've been able to get the fog off is to have the car royally blasting heat/defrost. It can't be like this all winter, can it?

I'd be so appreciative if anyone can tell me what they do!

What temperature setting will comfortably heat the car and keep fog away?
What fan and defrost setting do you set it on?

I tried just the seat warmers and no heat/defrost. That was comical. Within minutes I couldn't see out the window.

 

[ewoodrick]

The best solution is to keep the windows cracked to release the additional moisture that your body adds.

But I believe that the A/C default is cold on windshield and hot on occupants, which is a better long term solution.

Although I'm a fan of lots of warm air on the windshield to start with.

I just keep the system on Auto and let it solve the problem.

I know that a lot of people hate Auto, but while on auto, I don't have to worry about it and rarely hit any control.

 

[Petrlol]

First make sure your glass is clean. It takes like a year for everything to off-gas.

I find that manually setting the HVAC to 68+ towards the windshield (top left button in the HVAC menu) with a speed of 5 or 6 works pretty well and isn't obnoxiously loud.

 

[mreynolds767]

Had this problem last night in a cold rain. The combo of slow auto wipers was also a contributing factor.
When I had the Defrost on High it was fine and the wiper action seemed good, other than me melting of course and also I am sure wasting battery

Once I turned the Defrost on not high (blue setting or off) the windshield would become dangerous to drive.
Auto in the cabin did nothing, the car needed defrost on high to see clearly out the window.

After struggling with this for an hour of a 90 min drive and blaming the car defrost ; I switched the wipers to High manual not to Auto and was then able to see well enough with the defrost on the blue section, temp of 69 rest of the drive.

I am thinking someone else will have a better solution but in my case the auto wipers were too slow but was not a noticeable problem if the windshield was kept completely clear of fog so a combo of 2 issues in my case.

Still seems an issue to me the defrost only offers the blasting heat high option or a barely functioning low option. Need something in between.

 

[SVMike]

If you press the front windshield defrost icon/button you get cold air blowing on the windshield. This is supposed to dehumidify.
But if you press the button a second time it switches to heat. (illuminates red instead of blue). Try both.
I find that the defrost works pretty quickly, but a lot depends on the local weather.

Also, use the app to do this a few minutes before you get into the car.

 

[mreynolds767]

Yeah red defrost works great but also makes the cabin 1000 degrees of sauna like dry heat
I can only stand it for a minute or two

The blue setting barely works

 

[toolman335]

It sounds like this is an unsolved mystery lol. The red defrost icon sets it to 81 degrees, correct? As soon as I tried turning the temperature down the fans went quiet too. It's like playing whack a mole.
Totally agree that this car struggles to drive in the rain. I get the blindspot detection warnings, the auto wiper function is awful, and the windshield fogs up way too much.
At some point there will have to be an update with a middle ground to balance battery use, excessive heat, and the fog.

 

[Watts_Up]

To get a very fast defrost, I click on the special icon buton (there is one for the front and one for the rear), and put on red, instead of blue.
The defrost start after few seconds, with the fan blowing very high.
Works very well.

But after a minute or so, the fan is too strong and noisy. So I press on the central AC/Heat button to adjust the fan speed.

 

[hugh_jassol]

I just keep the system on Auto and let it solve the problem.

This is the correct answer

 

[toolman335]

If I leave mine on Auto I start to melt like the bad guys in Indiana Jones.

 

[ewoodrick]

If I leave mine on Auto I start to melt like the bad guys in Indiana Jones.

Then turn the temperature down.

 

[hugh_jassol]

Then turn the temperature down.

LOL!

 

[ChrisH]

So bizarre. I’ve never had to do anything and I’ve just left it on 69 degrees auto. I’ve had foggy windows once in 15 months of ownership. Tail light lenses and fog light lenses are another story lol.

 

[Jdee2wheels]

First make sure your glass is clean. It takes like a year for everything to off-gas.

This. I had really bad fogging issues last fall, and after cleaning the window really well, the problem was solved. Started getting fogging again with the weather change in the past few weeks and a good cleaning of the interior glass fixed issue again and I can just run HVAC on auto with no issues now.

 

[toolman335]

Then turn the temperature down.

Then I CAN'T SEE out of the window due to fog. That's why I started this thread.

 

[toolman335]

This. I had really bad fogging issues last fall, and after cleaning the window really well, the problem was solved. Started getting fogging again with the weather change in the past few weeks and a good cleaning of the interior glass fixed issue again and I can just run HVAC on auto with no issues now.

That sounds like a good idea to try. In 6 weeks of having the car I only cleaned the window once. Thank you.