What is the correct operation of climate control and a/c

[rapport25]

I know I have asked a simular question before relating to a/c working in colder tempertures.

My problem is like today for example. Dont like using deicer. I use and have used since driving luke warm water froma tap poor over all windows to clear no scrapeing. Jump in and away you go. Air con is working as it should as Im told on and off with climate. It does not work all the time at low temp like -3 to 3 like this morning.

The thing that concerns me is the back window seems to steam up and back windows

I maybe wrong but I was sure my 406 would clear all windows in the cold and has done over previous years.

Can anyone suggest anything?

Im thinking water lying in the car somewhere? Have not found any yet!!! Pollen filter needs changing which is due in January with its service.

Or do I have an a/c issue? Any help please

[teamster1975]

Have you had a look under the carpets Rappy?
I remember Steve mentioning something about a drain hole in the cill getting blocked ...

[steve_earwig]

I don't think water in the sill would be able to enter the passenger compartment. I could be wrong of course. There's always the swimming pool in the boot thing.

[trem1]

my 406 used to do this check your rear seat at the base where it meets the backrest mine used to let water in somehow and would fill up under the rear seat i never did find out where the water got cos i drowned it before i could do you park facing downhill cos thats when mine let water in if i parked facing uphill it was fine thats as close to a remedy i got to,hope this helps in some way

[rapport25]

Water getting in great thats what I thought It might be. No sign of water getting in though and everywhere seems to be dry.

Once Its light I will try and get to have a good look around the back seats. And where the spare wheel sits.

Only happens first thing in the morning though. Driving home from work it does not steam up at all. It reminds me as if it steaming up though mmmm.

[rapport25]

Just been outside to have a feel and a look around in the dark

Have taken spare out and had a real good feel under all the carpets and all are bone dry until I got to the passenger side front that is .

Its not soaking wet just feels a bit damp and sticky and no I dont mean that kinda sticky .

Imk thinking oh sh*t heater matrix has a slight leak but surely It would steam the whole of the car up?

What are your suggestions? Buy some rad weld? Or Is a drainage hole simply blocked up? How easy it to remove the carpet to get underneath and have a good look around?

Also I park on a flat and wash the car on a flat.

[mjb]

The sticky could just be from the muck that gets rubbed into the carpet every time someone gets in... Does it smell of coolant?

[rapport25]

The problem is the a/c from what I can see. Carpet is just were the mat rides up and wet/muddy feet leave it a little wet as I found tonight.

I had been told previous the a/c will cycle on and off below 8 degrees have found today I can manually turn the a/c on and off at 2 degrees.

Which in turn aids the de misting process as this morning was a nightmare car was steamed up very badly.

Tonight stuck in traffic again!!! window down I can hear the a/c clicking on and off and its only 2 degrees?.

What is the best setting to clear the steamed up windows as mine has never had this problem and Im sick of very poor visibility

front screen a little steamed up and front side windows. Rear windows you cant see out off and rear the same unless you keep heated rear screen on all the time

For once the pug has got me playing a guessing game.

Getting very pissed off now

[steve_earwig]

Beats me, I always hit the de-ice/mist button and it clears up almost straight away. Maybe your air con is broke

[rapport25]

Pollen/ cabin filter change this first thats what my a/c guy suggets.

I shall be getting one at the w end and hopefully that will sort it. Along with a nice shinny new cambelt/ water pump and tensioner

[mjb]

What is the best setting to clear the steamed up windows as mine has never had this problem and Im sick of very poor visibility

'windscreen' vent selection, close all the dashboard vents, fan on max, a/c on, recirc off, stop breathing

When it's cleared I just select 'all vents' and hit 'auto'. In the cold, the cc has to use recirc as the outside air's too cold, but that'll trigger condensation so it uses the a/c to dry the recirculated air

[Welly]

Using your a/c at this time of year only adds to the moisture in the car as it condenses out in the evaporator box and then when you park up the sun may come out, then it may rain, then it goes really cold and the moisture in the cabin condenses as a mist inside your windows. In other words yes the a/c might clear the moisture but it comes back! your best to have the whole system/ducting dry.

I haven't got a/c now but then again the same applies as last year I never used it in winter.

My car does NOT steam up at all!

The recipe is simple:

Very clean inside windows.

Run the climate in auto with the a/c off and use the Up and Down symbols (windscreen and feet) then if the screen mists at all give it a 30 sec blast using the full sceen mode with a/c off.

At this time of year the humidity in the outside air is very low (around 45%) so it does a sterling job of clearing the screen anyway. Give me a rainy March day at 10 degrees and 4 wet occupants jump in then yes the a/c will clear quickest but on your own at this time of year it does very little.

When I said about the a/c cycling on/off I mean that I observed it cycling like this below about 8 deg's whereas above 10 deg's it appears to run continually with no cycling so yours is dong the right thing. It won't run at all at 0 deg as a safegaurd (this is also why I never use it in the cold).

I'd say some excess moisture is in your car and maybe the pollen filter is soaked - check the splashguard is in place at the bulkhead/screen and check that the foam backing here hasn't fallen onto the pollen filter like mine was once.

You need to dry the interior over a few days using heating only then keep it dry with a/c off.

You're not running it on recirc are you? or has the recirc flap stuck closed?

[mjb]

At this time of year the humidity in the outside air is very low (around 45%) so it does a sterling job of clearing the screen anyway.
...
You need to dry the interior over a few days using heating only then keep it dry with a/c off.

You're not running it on recirc are you? or has the recirc flap stuck closed?

The trouble with this time of the year is the outside air, while nice and dry, is freezing cold and won't heat up that much from its brief encounter with the heater matrix. If you want warmth, you need recirc+aircon a.k.a. "auto".

I think the biggest cause of misty windscreens when sub-zero is a clogged up drainage pipe (where the condensation from the a/c heat exchanger drips down onto the road) and dirty windcreens

[Gurdin]

From my experience it was caused by th ere-circulation being on in the demist cycle.

I was told that it has a higher humidity level when in re-circulation mode hence the nisting up.

Once i had turned it off the problem was solved.

Stu

[rapport25]

Have just been checking over old service records I have not changed the cabin/pollen filter since march 2007 car has coverd around 25k since it was last changed Im guessing that must be the issue. Also I will try what has been said above.

Many thanks,

Rappy