OK peeps, its that time of year when the fucking windows get misted up all the time......I am someone who HATES people wiping the windows on the inside, i would rather sit there for 10 minutes while they clear

Some people say put the Air con on cold so it matches the outside temps--That will clear it quick

Others say

Put the heater on hot and flat out and it will de-mist it.......

Or drive with the windows slightly open......

Ect ECt

What do you do....as it is pissing down where i am and i had a right old game trying to de-mist the car earlier

 

turn heater on full blast and open window

 

buy a bloody ford you losers! heated front screens.

they own the patent on it so no-one else has it.

 

personally for me, windows shut and fan blowing luke warm on the whole journey. I found if its too hot it doesnt de-mist as well. Sod letting the rain in or using the aircon.

 

I agree.
I hate wiping the windows, but seeing as the heaters bust I dont have much choice.

 

air con will clear it in seconds.

 

didnt know that!

 

Jaguars had them for a bit, but they were owne by Ford.

 

It expired recently anyone can use the idea.

.

 

i hate it when the little one draws on the window

i have air con on luke warm

 

air con on luke warm?

Air con is freezing cold, if its not its called a fan

 

Prevention is better than cure - so...

Garage with a radiator?

 

It mists up when the car leaves the garage...............

 

Air con on hot or cold will demist, as it dries the air removing the moisture in it.
Indeed the patent did expire for ford, and a lot of cars can be got with heated font now, even get one for me other halfs mk3 astra(Ł165).
I don't get much misting as before I come to a stop the night before I open all the windows etc put heater on full cold and chill the interior as much as possible, works a treat, not 100% effective but not far off.
tabetha

 

Tiff, in me VRS I press the "Front Screen" button on the air con and it clears within 30secs when the car is warm or I open the window and it clears in about 1min. Keeping the rear window demisted is very hard tho, unless you constantly have the heated rear screen on all the time.

 

Is that true neil ?

 

Air con can be used with FULLY HOT setting as well as cold, air con only has one heat ability/temp so hotter air can be added if too cold, you cannot blow cold, it works by removing heat already there.
tabetha

 

Not if you take the glass out

Might be a bit nippy tho

 

i found in my old mk5 if it was damp outside it would mist windows open or not. The best way i found was air con on and windows open. Murdered my fuel economy (what little i had with a piperx induction kit lol) but did the job!

 

Ill stick to my fan/air con i think

 

i stand corrected then, i always associated air con with cold

 

use a dehumidifier from woolworths,4 quid. its a white tray of chrystals that take water out of the air

 

LOL

I bought an advent calendar from there, all the windows were boarded up and there was fook all inside!

 

On the Mondeo we have i just turn the heated windscreen on then press the max button on the dash that turns all the heating controls to maxium heat then wait a few seconds then drive off i didnt even scrape the windows the other night when they had ice on just done the above then after a few minutes it was clear


Brian

 

it always was.as said above maybe the patent ahs expired now.but ive not seen any other makes since

 

Mondeo Ghia X

Get in, turn on engine, hit heated front and rear screens, use the clear front screen control on the climate control and drive away with a clear view inside a minute.

Ace

 

1) Keep the inside of the screen clean then! Reduces misting up, and glare.
2) Maybe you have water ingress under the carpets, so the inside is never as dry as it could be which isn't helping
3) Put the heater on full chat. And blowing at the screen only
4) Worry about something else PLEASE!

 

yup

all i do is leave the climate on after the screens demisted and it's either est to 22 degrees or 19.5 when it's hot

 

It is a pet hate of mine with people who drive while demisting their windows using only a 'port hole'.

 

the answer to your question mark is to constantly refresh the air in the cabin. the blower sucks air in to pressurise the cabin and it is vented out the back. if you turn off the blower, or only have it on a low speed with a lot of people on the car, the air volume in their will not be exchanged enough and the humidity builds up and condenses on the cold windows.

you should never switch off the blower (in fact some cars, especially fords, don't let you and the fan speed zero position has a very low fan speed) and use it as high as possible at all times. also make sure that you are in fresh air mode and not recirculating. keeping the air blowing over the screen and foot position is good as it drys out the carpets from wet feet.

basically, most car manuals tell you how to use the HVAC, why can't people read them properly?

as you rightly say tabetha, a/c works in demisting by effectively drying the air passing through the cooling coil (the evaporator) as the moisture in the air is condensed there. it then drips offf onto a drip tray and out of the car down a drain tube.

the problem is, when you then switch off the a/c or stop the car, the air is still going through the evaporator coil and any remaining moisture will make it's way back up to the windows where it will again condense.

you are not right that a/c only has one temperature. that is how it worked in cars in the past, but rarely any more. it used to be that the compressor would be on until the evaporator was about to freeze up at which point the thermostat would switch it off and then on again a couple of degrees higher. the temperature was effectively controlled by that cycling action, and then you could also add hot air to it as you say if you didn't want air that cold blowing by either air blending off the heater coil or controlling the amount of coolant flow through the heater.

however, in more recent times the cooling capacity of the compressor (which obviously increases as engine speed increases) can be controlled. that is so that the compressor can be large enough to give sufficient performance at idle, but not too big so that the evaporator would freeze too quickly. this has been internally within the compressor for years (known as internally controlled variable displacement) and typically means that the compressor can have a displacement of anywhere between 5cc per revolution giving a cooling performance of only a few Watts to 160cc per revolution giving a potential of over 10kW at high speed.

that was all well and good, but it worked by controlling the pressure in the evaporator so that the temperature always remained just above freezing point, meaning that hot air still had to be added when maximum cooling was not needed and for demisting.

what's the problem with that you ask? we all know that car manufacturers are under increasing pressure to meet emmissions and fuel consumption targets, and cooling air to 0 deg C using a/c and then heating it again to 20 deg. C wastes power and hence fuel.

nowadays the displacement of the compressor can be controlled electronically so that the exact cooling demand can be met without over cooling and then adding heat. all good stuff.

in building air conditioning systems, the compressor capacity is not dependant on engine speed like in a vehicle. it was common practice to have large compressors and then cycle them on and off like in a car, but that industry is now more energy concious and the speed of the compressor is now normally controlled by an inverter to match the cooling demand as cycling on and off causes high current consumption.

 

we have air con thats adjustable from 17 degrees to 31 or is that climate control

 

All i do is start my van up, put on the air con and blowers on warmish, lock it up and go back inside for 5 mins then come back out and drive off!

Job done!

 

Do what?? Air con is air con, the temperature is irrelevant! Air con on warm demists considerably faster than 'normal' hot air!

 

Lick them?

 

that's climate control. read my large post above and you might understand how it works a bit more

 

yeah thats another thing i didnt like about my escort gti, when the fan IS NOT on theres no air what so ever coming from the top/side dash vents, same on my dads escort estate but on my beemer theres always abit of air coming through, so even if i dont have it on i can still see out of all the windows, but having the blower on makes them clear quicker/ stay clear

 

Thanks for that nick, most interesting, a lot there about more modern stuff I didn't know, think I'm a bit behind!!
tabetha

 

One thing I must admit I am amused at is people with aircon on and windows open

The evap is doing its best to remove all the moisture from the air, and your letting it straight back in through the windows - complete waste of effort & fuel!

 

air con takes the moisture out of the air - or says it sayd in my dads subaru booklet thingy

 

i normally wipe some soap or bubble bath on the window with a damp cloth. stops the windows misting up in the first place. i do it on the lorrys at work & it works a treat. also use it on the bathroom mirror to stop that misting up