If your windows gets foggy you need to turn up the heat as that lowers the relative humidity and direct the air towards the windshield, also check below the floor mats for water. If your car is a swimming pool your windows will be foggy forever.
Life is hard
Submitted 1 month ago by ickplant@lemmy.world to [deleted]
https://lemmy.world/pictrs/image/bf4c47f6-4dda-4f98-9498-f074856efac3.jpeg
Comments
Junkers_Klunker@feddit.dk 1 month ago
SchmidtGenetics@lemmy.world 1 month ago
Counter intuitively, you want to turn the a/c on as that pulls the moisture out of the car.
During winter when a vehicle is defrosting, it runs a combination of ac and heat to defrost windows and condition the air.
Junkers_Klunker@feddit.dk 1 month ago
If your car has that, then yes.
AspieEgg@lemmy.blahaj.zone 1 month ago
When I press the defrost button in my car, it turns both the heat and AC on at the same time. I assume this is to remove water from the air with the AC, then warm up the air increasing its capacity to hold water with the heat.
marretics@discuss.tchncs.de 1 month ago
Your assumption is correct Also your car automatically calculates the condensation point and keeps the temperature and air moisture low enough not to cause any fogging on your windshield. Source: I’ve been programming AC unit controls for cars for the last 10 years
ayyy@sh.itjust.works 1 month ago
How upset do you get when your buddy disables auto and proceeds to slam back and forth between full heat and full ac while claiming their shitty dial dj set is somehow waaaaay better than the computer?
MML@sh.itjust.works 1 month ago
They only do this with the automatic controls not basic knobs right? Apparently affected what filter I had to get.
weps@lemmy.world 1 month ago
thank you for your service
nova@lemmy.wtf 1 month ago
in a lot of newer cars they can actually use the A/C to heat and cool the car, rather than using excess engine heat or an electric heater which is especially helpful when it’s cold and you’ve only just started the engine!
takeda@lemmy.dbzer0.com 1 month ago
Fun fact (well, I suspect you know this already, but some didn’t, I had discussion with someone arguing with me that this is not true):
AC and a heat pump are basically the same thing, AC is just pumping the heat outside instead of inside.
Also when you say modern cars I am assuming you might be talking about EVs. Using a heat pump requires less energy than using resistive heating so it could be energy saving measure.
ICE cars on the other hand can get the heat from engine “for free” (not really, but since the heat will be produced anyway whether you use it or not, so why not use it?) so a heat pump might make a bit less sense in them.
boonhet@sopuli.xyz 1 month ago
I assume you mean EVs with heat pumps? I don’t know of any ICE vehicles that do this, seems inefficient to waste mechanical or electrical energy when you have perfectly good waste heat to use upon reaching operating temperature (though you may need to use an aux heater before reaching that, particularly on diesels)
MissingGhost@lemmy.ml 1 month ago
My car is a diesel so it takes a long time to warm up in the winter. They added an electric auxiliary heater to compensate. The air is really hot within seconds.
AspieEgg@lemmy.blahaj.zone 1 month ago
My car is an EV, so it definitely does this because there’s no excessive engine heat to use.
LotrOrc@lemmy.world 1 month ago
Yall have a defrost button?
kestrel7_7@lemmy.world 1 month ago
It’s not about temperature is about condensation and humidity. Turn on the AC regardless of temp (e.g. even if it’s cooler out and you’re blasting the heat) and the defog too.
Source: I fucking live in Seattle and it fucking rains all the time
QuinnyCoded@sh.itjust.works 1 month ago
but if I leave the AC on for too long I get mini fogs where the air blows
deaconblackhorse@lemmy.world 1 month ago
Always use heat. Anytime you have a fogged up window heat will cause that moisture to evaporate. Cold will always make the window cooler which causes more condensation.
chiliedogg@lemmy.world 1 month ago
It depends. The air conditioning will remove moisture from the air while cooling th cab, so the condensation can only form on the outside, where you have wind and windshield wipers to wipe off the condensation.
ayyy@sh.itjust.works 1 month ago
Nope
over_clox@lemmy.world 1 month ago
People in comments assume the heat or air conditioning even work.
Air conditioning also rapidly reduces humidity, so that tends to be the ideal option.
But if neither heat nor air conditioner work, well tough it out and roll the windows down…
Lemmyoutofhere@lemmy.ca 1 month ago
If neither the heat or A/C work, you shouldn’t be driving that POS on the road.
Gerudo@lemmy.zip 1 month ago
Just because the ac/heat don’t work it’s automatically a POS that’s not road worthy?
over_clox@lemmy.world 1 month ago
Our heater does work, just no blower motor, so if we need heat, just open the vents and drive for airflow.
Our air conditioner unfortunately does not work, but we have manual windows that roll down by hand for airflow.
And today I just happened to install a fan on the dashboard.
Yes it’s a piece of shit truck, but ignoring the ‘luxury’ features that cost more than the truck itself to fix, it’s pretty darn reliable.
See my previous posts regarding Kermit the 96 Sonoma for reference. More reliable than new model Ford trucks that brick themselves because rainwater got into the taillight assembly…
boonhet@sopuli.xyz 1 month ago
Buy them a new car then?
kestrel7_7@lemmy.world 1 month ago
My truck doesn’t have working heat and never had AC, and I will never stop driving that POS.
Mac@mander.xyz 1 month ago
Clean your window.
Boozilla@sh.itjust.works 1 month ago
Yup. The inside of the windshield gradually gets cloudy from all the plastics inside the vehicle slowly off-gassing. Soapy water, a squegee, and a microfiber do wonders.
NathanDerWeise@feddit.org 1 month ago
Huh, that makes sense. I was wondering what caused that buildup slowly over time.
arotrios@lemmy.world 1 month ago
Lemmyoutofhere@lemmy.ca 1 month ago
That’s REAR defrost.
arotrios@lemmy.world 1 month ago
Umm, no shit Sherlock? It’s literally in the picture I lifted from wikihow - just happened the rear one is circled.
Here, let me provide a version suitable for your comprehension level:
Meron35@lemmy.world 1 month ago
Useful mnemonic: Rectangle for Rear defroster, Fan for Front defroster
Bahnd@lemmy.world 1 month ago
They make cars with buttons? I thought ever car made after 2020 had an tablet taped to the dashboard …
Imgonnatrythis@sh.itjust.works 1 month ago
If you have a fancy new car without one just yell at your on board AI system until you start crying and then the tears are more blurring than the fog and you just don’t care anymore.
ChicoSuave@lemmy.world 1 month ago
Defrost turns on the AC and blows cold air. That temporarily removes the fog and keeps the cabin cold. The alternative is to use max heat and let the hot air raise the cabin temperature which will help clear the fog.
And it stays gone too. Using cold causes the fogging to return if hot air or the heater is used in the cold car. The defrost button is a myopic solution which ignores user comfort.
HeyThisIsntTheYMCA@lemmy.world 1 month ago
the fuck. that’s a white circle, not a red circle. i’m so confused.
Grostleton@lemmy.dbzer0.com 1 month ago
Humid and warm: use heat
Cold and dry: turn on a/c
over_clox@lemmy.world 1 month ago
I think you got the right idea, just backwards…
Assuming your heater, air conditioner, and blower motor all work correctly, you should use your heater defroster in cold weather, and your air conditioner defogger in warm weather.
Note the difference in environmental control terms…
- DEFROSTER > Used for cold climate, heater, to melt the frost off your windshield.
- DEFOGGER > Used for warm humid climate, air conditioner, to dehumidify the air.
Failing either heater or air conditioner, welp, just do what we do and roll the windows down.
Lemmyoutofhere@lemmy.ca 1 month ago
Both of those settings turn on the A/C to remove moisture.
rumba@lemmy.zip 1 month ago
Trick question:
Dew point is the exact temperature at which the current level of humidity forms. Heat is good because it makes the air at the surface stop condensing. AC is good because it dries the air out forming the condensate in your air box. Cracking the window is generally enough warmth to interrupt the process. Most new cars have a defrost mode that turns on both heat and ac to dry the air out.
So the answer is do anything, except just turning the ac colder.
Sam_Bass@lemmy.world 1 month ago
crack a window
tigermountain@lemmy.world 1 month ago
Open the window.
funkless_eck@sh.itjust.works 1 month ago
match the temperature outside.
if it’s cold out you need to make it colder inside
if it’s hot out you need to make it hotter inside
the condensation is caused by difference in temperature.
yes, it may be inconvenient or uncomfortable
Kolanaki@pawb.social 1 month ago
If you have a defogger setting the temp doesn’t matter since it will basically just heat or cool the windshield on both sides. eliminating the differential that causes condensation.
FishFace@piefed.social 1 month ago
How will it being hotter outside cause condensation?
funkless_eck@sh.itjust.works 1 month ago
same as vice versa - water vapor in the air cooling and becoming liquid
if your AC has too much water vapor or you have dampness inside the car (sweat, water, damp clothing) it can exacerbate it
Malica@lemmy.zip 1 month ago
Temp isn’t as important as ac
Widdershins@lemmy.world 1 month ago
Remember to pull your sun visors down. My AC doesn’t stay charged so I have to rely on heat alone to defog windows. The visors trap the warm air.
kalkulat@lemmy.world 1 month ago
Just the other day I was listening to this song by the Grateful Dead:
"Sometimes the light’s all shining on me …
Sometimes I can barely see …
And lately it appears to me
What a long strange trip it’s been. "
some_guy@lemmy.sdf.org 1 month ago
Every time. And I’m halfway through life. I could do a web search, but who ever thinks of that except when this happens? Will I do a web search now? No. I have other stuff to think about. And so it goes.
MyVeryRealName@lemmy.world 1 month ago
Atleast you have a car
belsedar@slrpnk.net 1 month ago
The best situation is when you don’t need a car to simply exist. That should be the norm, not the exception.
MyVeryRealName@lemmy.world 1 month ago
I live in Asia and we don’t need cars to exist (unless you’re in Dubai)
Dyskolos@lemmy.zip 1 month ago
In the Netherlands I would switch to bike. Here (kraut), not so much. And public transport is a nasty nightmare. Nah, car it is!
DioramaOfShit@lemmy.world 1 month ago
Uhhh the defrost button? Arr people that dumb?
yucandu@lemmy.world 1 month ago
American cars: “This obviously requires the AC.”
quadrant5835@lemmy.zip 1 month ago
That’s when I just put the airflow on “feet”. Most cars will actually blow like 30% up on the windshield when set to the feet direction. This lets me avoid running the a/c if I don’t want to.
athatet@lemmy.zip 1 month ago
67^o^
blackberry28@sh.itjust.works 1 month ago
Bro turns his car into a sauna
boonhet@sopuli.xyz 1 month ago
67C is a pretty old sauna, I prefer it at like 80-100 myself
thethrilloftime69@feddit.online 1 month ago
Whichever of the AC/Heat is on, just switch it to the other one. Or turn it off. Or open the windows.
likebudda@reddthat.com 1 month ago
The fog is moisture condensing on the cold windshield surface. Use heat directed at the windshield with AC on. The AC dries out the moisture and the heater warms up the surface preventing additional condensation.
ceenote@lemmy.world 1 month ago
If it’s already cold, you don’t need to turn the AC on. The air will be dry once it gets warmer.
LORDSMEGMA@sh.itjust.works 1 month ago
Defrost setting uses the AC unit. Helps pull moisture out of the air
4am@lemmy.zip 1 month ago
This is wrong based on the assumption that it works the same in all areas of the world, but I’m not sure if this is -10 votes wrong.
Especially considering some of the other posts I’ve seen on here and how they get voted on
Reygle@lemmy.world 1 month ago
This can be correct in northern winters, with very high humidity this will only fog the windshield much worse.
JcbAzPx@lemmy.world 1 month ago
I’ve tried that. It only made things worse.