Intresting. 

I don't use aircon in the car as it generally sets me off sneezing  but when you hit the auto button to defog the windscreen it does put the aircon on and I do turn it off as soon as it's clear and go back to my usual settings si perhaps with only doing short journeys it could be down to the aircon being on and the moisture being trapped. 

Will try and remember on the next frosty morning not to press the auto button and individually select front and rear heated screen and see if that makes a difference. 

Here's a weird thing...

On Monday morning when I got into my Fiesta to make a journey I was faced with a windscreen covered in the usual large water droplets, as per the photo I posted a few days back. I was sitting in my driveway with the 'Max' button depressed for nearly ten minutes before I could set off safely.

About five minutes into the journey I decided that the screen was clear enough to cancel the 'Max' button, and when I did so all the vent settings returned to normal levels, but only for a minute or so.

After that minute of normality, I heard that the vent fan was winding up to maximum again, and it was blowing very hot air. However, the fan control knob had no amber lights around it to show it was on full, and nor did the temperature control knob show 'Hi'. They were both blank. It was as if the whole ventilation system had run out of control, entirely of its own volition...

To try to re-set this uncommanded state of full-fan and high temperature I turned both knobs fully anti-clockwise, and fortunately that did the trick. I was now able to use the knobs to re-adjust the levels back to what I wanted, and all was well again after that.

But... And here is the point of this post. When I got into my car yesterday morning the windscreen was crystal clear with not a drop of water, mist or moisture on it! This was the first time in weeks that I'd found it like that, and overnight weather conditions were not greatly different from those previous weeks of regular condensation.

And the same thing happened this morning; there was not a bit of fogging on my screen at all; crystal clear. (I was actually early for where I was going, because I've got into the habit of going out to the car five minutes early so as to allow time for the condensation to clear...)

I'm finding it very difficult not to suspect that what happened on Monday, when the ventilation system went out of control, hasn’t in some way got something to do with this remarkable change.

Has anyone any idea whether it might be possible for something in the vent system to remain active when the rest of the car is switched off overnight? I'd appreciate any advice so that I can point the dealer to a specific thing that might be faulty.

.

Having suffered with this issue last winter and starting to suffer with it again now I was determined to find the route cause. I discovered the front cawl had become unclipped from the front screen. This causes water to drain down the back and drip on to the sound deadening material. The warm engine causes evaporation and this makes its way through the vent to the wind screen.

To fix I removed the cowl. Unclipped the windscreen clip that runs the length of the cowl (it as only attached eather end but completely loose in the middle). Ran a bead of silicon along the clip to stop it coming unclipped again then clipped it back together then refitted to the car.  

.

Cjay,

Very much appreciate you're still working to solve this, but I can't quite picture what you mean by the 'cowl'.

Any chance of a photo to aid identification please?

Its the black trim along the bottom of the windscreen. Will post some pictures tomorrow when it's light.

Basically the water from the screen needs to run over the top of this black plastic and in to the internal gutter and Exit via the wheel arches. 

If it isn't properly fitted water runs underneath and down through the engine bay soaking  the padding fitted there  

.

It's not visible when fitted but basically there is a plastic strip that slides on to the bottom of the windscreen then the black trim that you see clicks in to it and holds it firmly against the glass. 

I need to carry out the same repair on a Mk7 so I'll post picture of correctly fitted and unclipped.

First picture shows correctly fitted cowl that cannot be lifted from the screen. Water runs over the top and in to the internal gutter.

Second picture shows loose cowl that allows water through. It can be Easily lifted off the screen 

Third picture loose cowl sitting slightly off the screen.

None of you have owned an Up! The damnned object needed wringing out every morning because it has no insulation at all. It gets cold and all the internal paintwork and the instrument cluster are wet. The mark eight has lots of different modes for the HVAC system. Reading and understanding the book helps but for those with misting issues: all on max,aircon and most importantly recirculation on clears the screen in two minutes.

.

 

 

 

22 minutes ago, anon said:

None of you have owned an Up! The damnned object needed wringing out every morning because it has no insulation at all. 

Lol. See my post on the first page of this thread:

"My Mrs's SEAT Mii used to suffer badly from the same thing. The heater plenum on those (and it's Up! and Citigo clones) is very prone to getting full of leaves which harbour damp which then finds its way inside when you use the heater. Thinking the Fiesta wouldn't suffer the same problem I started parking the Mii in the garage (after spending half a day cleaning/drying out the plenum), which seems to have solved that one, only to find it apparently happening on the Fiesta."

 

.

28 minutes ago, Chainsawcharlie said:

Don't get me started on toasters just now 🙂

Coincidentally we've just returned from a few days in a self catering apartment. Every time we tried to use the toaster it tripped the RCD in the fusebox!😃

59 minutes ago, Chainsawcharlie said:

Hi Cejay, many thanks for the photos.  I can't quite see from your photo, but when I checked my Cowell koint to windscreen, it appears to have like a silicon rubbery type of edging which butt's up to the windscreen, if I was to gently push the black plastic cowel in a little I can see how it would leave a thin gap upto the windscreen, but to me it doesn't actually look defective  I guess if there was a gap when I wasn't pushing the cowel in then maybe mine would be defective.

 

Does it sound like mine is unlike your faulty one was?

 

I would say my condensation is a light misting of the whole inside windscreen, not dripping but light misting, and only when really nippy outside.

 

I've edited this by adding photos of mine  particular attention to the line which is nearest to windscreen of course.

I opened the bonnet and had a feel of the fabric matting under the cowl, which feels dry

 

Cheers for the help mate.

Yours looks to be a  modified version perhaps to stop this issue. If water isn't going under the trim then I'd say your good to go.

1 hour ago, Eric Bloodaxe said:

Coincidentally we've just returned from a few days in a self catering apartment. Every time we tried to use the toaster it tripped the RCD in the fusebox!😃

I don't understand how it can be so hard to make a decent toaster with all the tech we have now.  I'm sure the control knob on mine isn't even connected at the back...seems to be a lottery regardless of where it's set! 

.

1 hour ago, Eric Bloodaxe said:

Coincidentally we've just returned from a few days in a self catering apartment. Every time we tried to use the toaster it tripped the RCD in the fusebox!😃

Ah .... was you digging out the toast with a knife or fork as it hadn't popped up properly....Once caught the daughter doing the exact thing 😮

4 minutes ago, Wino said:

Ah .... was you digging out the toast with a knife or fork as it hadn't popped up properly....Once caught the daughter doing the exact thing 😮

No, everything done correctly I can assure you! And we even cleaned out the crumb tray and checked carefully for any obstructions in the toaster.

Anyway, as we were in Scarborough it just gave us a good excuse to pop out for a good value breakfast at Cooplands which I'm sure you'll know.

Lord Rosebery was the venue for breakfast last time we was in Scarborough 😀

Condensation in toasters is to be avoided. Apart from the difficulty of replacing the cook, it makes the toast go soggy. My Up! was new and did not have leaves in the plenum. The engine was fantastic and it would do 90 mpg driven very gently but in every other respect you could think of, it was effing bad, so much so I could not in all conscience sell it so at eighteen months it was recycled as a tie down block for my aeroplane. Good Riddance to the hateful thing. 

Having now carried out the repair on 2 fiestas and now not suffering from misted up screens with the sound deadening material now bone dry. I can confirm the repair a success. 

.

It's so nice being able to jump in the car and go without having to demist the screen first for 10 minutes.