Heavy condensation on inside of windows

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discv
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Heavy condensation on inside of windows

Post by discv »

This problem has been an ongoing problem on my C4GP 1.6 Hdi. 2008. VF7**************[VIN obfuscated, can be read by forum staff]
The draining from the windscreen air intake and then out behind the front wheel arch liners are clear and working properly.

I feel that the solution has something to do with the air con drainage. I have never seen so much as 1 drop of water under the vehicle. A/C works fine.

Prior to my health taking a dive, I looked everywhere under the car for signs of an outlet- without luck.
I yanked out the driver seat, then the floor. But no water marking or anything looking like a vent tube.

So maybe the vent tube is under the passenger floor. But to have a look/see would need the services of a 'mechanic'. Scary stuff :(

I'm hoping that someone might know where the condensate vent is located- or if a keen eye on the parts listing gives a clue.
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GiveMeABreak
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Re: Heavy condensation on inside of windows

Post by GiveMeABreak »

The A/C generally has a tube that is in the engine bay (outside of the vehicle cabin) that allows water to drain onto the road - here is the water evacuation pipe (8) and box (9). You may not see a pipe as looking at it, on your C4 Picasso it seems to go into a separate box.
C4 Pic AC Pipe.PNG
I don't know how you operate your A/C, but the recommendation is to leave it the Climate Control on AUTO and ensure all the vents are open, which will allow full air distribution and remove the moisture from the vehicle. Turning the A/C off just allows the warm air to condensate on the windows again.

I leave mine on AUTO all the time and never have a bit of condensation so far this year. I expect there will be when the temperature drops, but it soon clears when the car is running. I know some people are paranoid and turn their A/C on and off all the time or close the vents up which pretty much stops correct operation.
admiral51
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Re: Heavy condensation on inside of windows

Post by admiral51 »

Just as long shot but the car is nearly 13 years old, have you checked the drainage on all the doors.
It was a while ago maybe 3-4 years but over time the window seals allow water to get into the doors and there is a drain hole for it to escape outside of the vehicle.
If the drain hole is restricted you may get a build up of water which will give you the problems you have.
I think there is a rubber bung on the underside of each door but i got lucky and just by shaking the door i could hear the water that had built up inside it.

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Re: Heavy condensation on inside of windows

Post by GiveMeABreak »

Yes, good point Colin ^
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Re: Heavy condensation on inside of windows

Post by Dormouse »

I have a poor fitting seal on the drivers door top - due to using a door held windscreen cover. This let water into the cabin and down to the floor. First sign was heavy condensation on the windows in the morning. Next sign was slight damp on the underneath of the rubber floor mat. A drying session with a fan heater cured the condensation problem until the next driving rain on the driver's door. That's when I discovered that the rain was getting in the top A post seal.
discv
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Re: Heavy condensation on inside of windows

Post by discv »

Thanks guys- lots of food for thought.
One thing sticks though- even though the A/C pumps out ice cold air, how is it possible that never so much as one drop of water has been seen on the road?
Peter.N.
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Re: Heavy condensation on inside of windows

Post by Peter.N. »

You haven't got the airflow set to 'recirculate' have you? - that will steam the windows up.

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Re: Heavy condensation on inside of windows

Post by discv »

GiveMeABreak wrote:
16 Dec 2021, 19:05
The A/C generally has a tube that is in the engine bay (outside of the vehicle cabin) that allows water to drain onto the road - here is the water evacuation pipe (8) and box (9). You may not see a pipe as looking at it, on your C4 Picasso it seems to go into a separate box.
I wonder what that 'box' [9] is all about- and where it is.
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GiveMeABreak
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Re: Heavy condensation on inside of windows

Post by GiveMeABreak »

Well the evaporator box is inside the car behind the dash. The pipe connects as shown below and then onto that box (9). From there - I couldn't tell you - here's the location on the evaporator box and secondly a close up of the unit (9). So whether there is some voodoo going on inside the box I couldn't tell you or maybe a second pipe that goes from the box - but if there is it isn't shown.

Maybe the box gets heated and the water evaporates - like all the water in a container on the back of a domestic fridge that gets evaporated by the compressor heat?
evac pipe.PNG
evac pipe b.PNG
evac pipe b.PNG (57.2 KiB) Viewed 46 times