Constant Steamed Up Windows!

[daxilic]

OK so it's winter time now and my windows keep steaming up, no problem...turn the demister on for a few seconds and it clears, but after I turn the heater back on the windows immediately steam up again, like literally 5 seconds after I just cleared them. The only way to keep the windows clear all the time is to have the demister/aircon on all the time while driving, but having to drive all through winter with the aircon on full blast and getting hyperthermia isn't something you should have to do. I've never had this problem in any other car, normally after demisting it wont steam up again. Is this some kind of design flaw or is there a problem with my car? its extremely annoying.

thanks.

[Rory]

its the other button on the middle (?) dial, make sure its bringing air from outside instead of recirculating, that'll reduce steaming

so the button has 2 lights on, one is the car with the arrow fully in, and the other is a car with the arrow going into it, thats the one u need lit

[sparkystav]

Having air con on wont make the air cold, you can have the aircon on with the heating.

in fact id suggest doing this as it helps dry the air and so creates less condensation

[ROYT]

its the other button on the middle (?) dial, make sure its bringing air from outside instead of recirculating, that'll reduce steaming

so the button has 2 lights on, one is the car with the arrow fully in, and the other is a car with the arrow going into it, thats the one u need lit

Also check for damp carpets or any water getting inside the car

[daxilic]

yea I use that button and the other one for air circulation inside the cabin only. doesn't make any difference :duh:

[daxilic]

where would water be getting into the car?

[lexynik]

water can get in down the bottom of the windscreen i believe - if yours is misting up that badly it would imply that it is indeed damp inside

[The Transporter]

Check that the cabin filer (Pollen filter) is clean and is passing air freely, it may need changing

[JollyRoger]

The air recirculation button allows already moisture laden air to constantly travel around the inside of your car and condense on the cold windows thus steaming occurs.

the air replenisher button brings fresh air into the cabin that may not be as humid, i.e not containing as much moisture.

Air con/ climate control doesn't cool the air but in fact removes the moisture from it which makes the air cooler,

example, stand out in a really hot day and feel the heat of the sun,and the move into the shade and feel the relief and feel cooler because your out of the sunlight?

example, in Malaysia its really humid i.e lots of moisture in the air, so step out of the sunlight into the shade and you cant escape the humidity.

so with the heater on, air replenisher button pressed and the air-con active will heat the cabin whilst removing the moisture and the windows steaming will clear.

Obviously the faster the fan speed and the air direction controls directed the right way the quicker the windows will clear.

[The Transporter]

Roger, I'm afraid that you need to learn what an air conditioner does and how it works... When the aircon is switched on, it cools the air. The humidity in the air condenses on the condenser, the result of which the realative humidity (RH) of the air reduces. once the air is cooled to approximately 6 centigrade, the air is then either passed through to the air vents or directed to pass through the heater matrix, or blends the air to maintain the required cabin temperature as set on the dial and sensed by the cabin temperature sensor.

[Jimxms]

I'm interested to hear how you manage to resolve this. Do you by any chance have full leather seats?

Reason I ask is that when i had a half leather IS200 i had no condensation problems at all, but with my full leather IS300 the windows steam up ALL the time. After lots of messing around I've come to the conclusion that the fabric seats helped a lot with absorbing moisture in the air, where as leather does not.

[Kelscot30]

I'm having the same problem, full leather interior, its driving me mad! Also, I've had the car 7 wks but putting on air con or any heat features lets out an awful smell! I thought it was the previous owner as I've found a few dog hairs and smells like he might have been a smoker but now I'm not so sure...Had it valeted etc and have left it on for some time to try and let it run through but it still smells really bad. Called the garage but they advised as it was not an electrical or mechanical fault there is not much they can do! Any advice?

[lexynik]

smells like that can be bacteria in the ac system - a full service on the ac by a specialist (not just a regas) should sort it out - a few diy methods available not sure how well they work - im sure the transporter can explain it all as its his specialist area i believe

[scudney]

I'm having the same problem, full leather interior, its driving me mad! Also, I've had the car 7 wks but putting on air con or any heat features lets out an awful smell! I thought it was the previous owner as I've found a few dog hairs and smells like he might have been a smoker but now I'm not so sure...Had it valeted etc and have left it on for some time to try and let it run through but it still smells really bad. Called the garage but they advised as it was not an electrical or mechanical fault there is not much they can do! Any advice?

hi have you tried changing the pollen filter behind the glove compartment,bet this solves the awful pong problem.

[Jimxms]

I think there's filters and sprays you can use to get rid of the smells. My aircon has a bit of a damp smell that I need to sort out when I can be bothered.

I'll definitely be trying some of the previous posts though. If all else fails, you could always shove these under your seats http://www.airandwatercentre.com/store/SEURLF/ASP/SFS/CID.42/PID.459/SFE/productdetails.htm

:P

[Parthiban]

Have you tried cleaning the window? You can also get products when applied to the screen stop them from misting up.

But as above keep the A/C on and keep the system on fresh air and mine never mists up (and as above don't need to keep it cold just turn the temp up!)

[Irish IS 200]

If the heater matrix is leaking the windows will mist up and only the air-con or open windows will clear them.

As regards the leather situation, I have full leather but no misting problems; if the air flow control is on "Auto", it will be more concerned with cabin temperature than clear windows. Try setting it to "Windscreen/Feet" beacuase the small amount of airflow to the screen will flow all over the car and keep the other windows mist free.

Mike

[JollyRoger]

Roger, I'm afraid that you need to learn what an air conditioner does and how it works... When the aircon is switched on, it cools the air. The humidity in the air condenses on the condenser, the result of which the realative humidity (RH) of the air reduces. once the air is cooled to approximately 6 centigrade, the air is then either passed through to the air vents or directed to pass through the heater matrix, or blends the air to maintain the required cabin temperature as set on the dial and sensed by the cabin temperature sensor.

Looks like you've proved my point, other than the air condenseness on the evaporator, as the condenser sits in front of the Radiator.

By condensing on the evaporator it is effectively removing the moisture from the circulating air, the moisture collected on the evaporator drips off into a drip tray and runs out via a tube onto the road, which is why if you have your air-con active on a hot day at a standstill, there will nearly always be a puddle of water under your car.

My post was rather simplified for those who may not understand the fundamentals of Air-conditioning without the need to give a Physics Lesson.

And i'm afraid that i know very well how Air-Conditioning works.

[daxilic]

thank you for all the advice, I've found using the air replenish button on with A/C on but heater on too does seem to stop the windows steaming up. If only there was a way to clear the rear side windows with vents lol.

I've got no leather or half leather seats there entirely fabric, dont think I've ever had a car with full leather seats so cant comment on that.

as for the bad smell kelscot I had the same problem over the summer, seemed to only smell when I put the aircon on. I sprayed loads of febreeze in the intake vents (where the windscreen wipers are) and it pretty much got rid of the smell, it's not completely gone but definately helped a lot :) failing that you could see if theres any blockages in the drip pipe from the evaporator.

where would I find the heating matrix?

[The Transporter]

Air con/ climate control doesn't cool the air but in fact removes the moisture from it which makes the air cooler,

Thanks for pointing out my Typo.... However the moisture condensing on the EVAPORATOR is a function of the air being cooled, If you didn't cool the air, then you wouldn't be able to dehumidify the air would you?. The cooled and dehumidified air is then reheated to give the desired cabin temperature. The fact that you feel cooler in an atmosphere of low humidity than you do in a high humidity atmosphere where the temperature is the same for both cases is because the sweat on your body can evaporate at a higher rate, absorbing energy in the form of heat as it changes from liquid to vapour...

None of this has helped the guy with condensation in the inside of his windows and so I shall suggest that he has a close look at his cabin filter as if it is clogged, then air could be pulled from round the recirc flap, essentially the heating system is in recirc mode. It is also possible that the recirc flap is jammed, press the recirc button and listen if you can hear a change in tone in the heater air flow, if it is drawing fresh air, then it will be noticably quieter than on recirc.. Another option is that the condensate pipe is clogged and there is water sloshing around in the drip tray under the Evaporator and moisture is being drawn back into the airflow making the air more humid again.

As for smelly evaporators, remove the cabin filter and spray evaporator cleaner into the evaporator box and leave over night. I use a product called Frionett Germ but since it is hard to find if you are not in the trade then some folk use plain old fashioned Dettol disinfectant spray, they say that it works well.

Try not to spray perfumes or air freshioner into the air conditioning as after a few days it can cause the smell to become worse, akin to cat pee

[Enda IRL]

Ive been havin the same problem! Comin home on a nite out i hada leave the 2 front windows down and the heat on full...dono how it worked but it did.lol

Read thru the convo an tink u's hav come up wif a slightly mor practical way of doin it!

cheers:)

[04AAA]

where would water be getting into the car?

Your breath and wet shoes/clothes.

[fjcfarrar]

Ive been havin the same problem! Comin home on a nite out i hada leave the 2 front windows down and the heat on full...dono how it worked but it did.lol

Read thru the convo an tink u's hav come up wif a slightly mor practical way of doin it!

cheers:)

When you drive in the winter, as the car warms up, all the moisture in seating, carpets and clothes vapourises. The IS 200/300 is not the best at venting all this out and the model steams up worse than many other cars as it cools and the moisture condenses on the coolest surfaces - like the windscreen. It helps to crack a window open when driving to let the vapour escape a bit better. Also if you park in the daytime where what sunlight there is shines into it, this heat will also vapourise moisture which then settles on the screen etc as it cools down when it gets dark; so it is better to park where the sun doesn't shine if you can. Heater set to screen at max speed with aircon ON clears it quickest, but you will often have to clean the screen before you can drive off. A blade is best for this.