Poor demisting? Any experience

[dagget]

Now the weather has got a little chilly I have noticed that the Octy seems a bit sluggish to demist.

Even with AC/fans and heater on it still takes a while to demist the screen, much longer than other newer cars I have had. Also noticed the inside of the rear screen stayed fogged up for long time as well.

Has anyone had similar experience, usually the AC would quickly clear the screen but this it didnt.

[dArK5HaD0w]

Mine demists pretty quickly, including the rear demister.
It gets very frosty & cold here in canberra!!

[candy_wagon]

I tend to find that if my windscreen is a bit dirty it fogs up easier and takes longer to demist. More so than in other cars I've had.

Run some Good quality glass cleaner like Meguiars over it and see if it makes a difference.

[zei20t]

mines fine! very fast

[gldgti]

the old taxi trick is to use a drop or two of dishwashing detergent on a paper towel, then clean the glass with that towel and methylated spirits.

I guess the other option is that you have some problem with your a/c. Certainly my octavia demists quickly enough.

I suppose its silly to ask if you had the airflow directed on the windscreen?

[dagget]

Thanks guys sounds like we might have an issue somewhere then. Everything is set to demist but it takes a while. Also get side windows fogging up.

Bit of context was last night it was damp and cold when I got the car from the station, took a good few mins of AC/demist before I could clear enough of the screen to start moving and there was still bits of fog on the screen 20mins later when we finally got home and the rear was still fogged except accross the demist lines.

However I will try simple things first and clean the screen - I have not done it since we got the car as it seemed pretty clean but who knows what was on it.

I also noticed my inner door seals don't seem as effective as they should be, with slight leaks so no doubt need an adjustment somewhere.

[deeps]

Mine de-mists fine - but then it mists up almost immediately after I turn it off. Might try the metho trick.

[dagget]

Mine de-mists fine - but then it mists up almost immediately after I turn it off. Might try the metho trick.

Had a look on Briskoda, lots of topics about condensation/ac/poor rear window efforts. Also reading that that AC does not work below 4 degrees! This would explain why it would not demist the window last night.

[Guest001]

Even cold air will demist a windscreen Have you got it on fresh or recirculate.

[zei20t]

you'll probably need to make sure the AC light is on. that will clear it in no time at all. dry air clears a window much faster

[PassatB6]

Had a look on Briskoda, lots of topics about condensation/ac/poor rear window efforts. Also reading that that AC does not work below 4 degrees! This would explain why it would not demist the window last night.

Press the demist Max button not just the ordinary demist. Mine works perfectly.

[wai]

Check the AC drain. If it is blocked, then you are going to be sending humid air against a cold screen.

[dagget]

Few things to check, sounds like something is amiss if everyone else has no problems will investigate to see whats what.

[Ocy_RS_TDi_Kombi]

I haven't driven my car for a few days and this morning I went out and it's was 0c with a totally frozen Ocy. The car fully demisted itself within a minute or so whist I was outside scraping ice off the windows/screen.

I set the fan to max, hottest temp and heat to the windscreen and hands. Oh I also set the mirrors to demist too. Works a treat.

[BottomScratcher]

Even cold air will demist a windscreen Have you got it on fresh or recirculate.

Many of the issues I had with the Climatronic in my Octy were from using it like all of the A/C units I had in other cars. It's different, and since following the recommendations in the manual I have been pretty happy with it. The book gives a table for optimum settings for varying conditions of use.

You mentioned cold and damp. Humidity is a big factor, and Hillbilly is spot on with the suggestion to use cold air and recirculate. And I mean cold, as in A/C cold.

Firstly, without going into what each function does in detail there are 2 settings on the recirc button indicated by two lights on the top of the button. One left, one right. Repeatedly pushing the button changes the setting and the lights. Make sure you've got it set correctly. Check the manual for the details. Unless its on recirc if it's cold and damp outside then you're drawing in cold damp air to dry an already moist surface. Won't work too well. Secondly, A/C cold air is often the quickest way to demist in damp, i.e. humid conditions. The cold and very dry air passes over the condensed moisture on the screen and pulls the moisture away leaving it dry and clear. Waiting for warmer air to do the job has a couple of added problems. As soon as your bum hits the seat extra moisture is being added to the cabin area due to your own body heat and your breathing lowering the dew point of the air inside the cabin. When the engine is cold try the cold air on recirc. Good luck.

Edit: I can't say for sure, but I'd wager a six pack that your side windows aren't demisting because your vents aren't angled towards them, so they're not getting enough, or any air flow from the system. The table I mentioned in the book is quite detailed. It not only lists control settings, but also which vents to open and which direction they should be angled for different conditions. If your outside dash vents are getting some air across the side windows they should be demisting.

I've found the rear compartment of my wagon demists very quickly. The filament glass heater system is of course very different to the air flow system from the Climatronic, so if it's working OK but not doing its job then it seems that it's struggling to dry the glass before more condensation is forming on it. That can only mean that there's too much moist air inside the cabin, which takes me back to the recirc button setting.