Interior condensation - Xantiargh!
Hi all

My car suffers from ridiculous levels of condensation on all windows with the current weather conditions. Its beyond just turning on the fan and waiting a few minutes, I have to wipe with a duster and wring it out, then wait for the fan to do its job.

I tried an anti-fogging liquid, but I don't think its up to the job.

What can I do to reduce the condensation, and what is causing this level of it? I have checked the carpets and nothing is damp.

Would putting a cover (window level, not whole car) reduce it? Its a pain first thing in the morning, specially when its frozen inside and out...

Ta muchly
Interior condensation - solara
Try turning your vent control to the OFF (closed) position overnight, or point it down to the footwell. I suspect your windscreen drainage vents are blocked up, hence causing the condensation.
Interior condensation - nick
Surely it would be better to clear the vents?

Are you sure there is no leak into the interior? Or the boot/hatchback?

It could just be wet feet when you get in.... what you need is a nice set of mats (carpet of course) :D
Interior condensation - Xantiargh!
I'll have another scout round for leaks, but there's no damp smell, and I haven't noticed anything when I've been cleaning it.

Where are the vents likely to be? Back of the engine bay by the windscreen wipers? Probably should ask this on a Xantia specific site.

Treated car to shiny new carpet mats when I got it (worth almost as much as the car!).
Interior condensation - RichardW
Check the passenger footwell carefully. If the scuttle panel (the plastic jobby the windscreen wiper spindles poke through) is not fully bonded to the windscreen, water gets underneath it and runs straight through the heater fan. Also, if the heater matrix is leaking this drops water into the same place - I think it can also end up only under the carpet, and it appears dry to the touch!

Check also under the rear seat - blocked sunroof drain lines tend to end up with the water accumulating here. The boot lid can also leak around the wiper spindle.

You don't need much water to make a lot of condensation!


Is it illogical? It must be Citroen....
Interior condensation - Rdw
I wouldn't worry too much, it is the weather conditions at the moment, cold with high humidity, even with aircon on mine will not clear. Just ride it out and wait for the summer!
Interior condensation - M.M
Spot on Richard as usual!

One extra thing though...have you got aircon? Not a blocked pollen/cabin filter that no-one has ever found to change? That will make demisting very poor.

Interior condensation - M.M
My Xantia clears pretty easily and stays clear.

Rob you've got aircon so how about your cabin filter?

Interior condensation - xantmark
have you got the air flow lever on the heater control swithed to recirculate or fresh air if its on recirculate it wont clear found this out when we had snow at begining of year
Interior condensation - Xantiargh!
No air con. Used to love the air-con on my last car, cleared the screen in no time.

This is different though, not foggy, but full-on Victoria Falls.

I'll have a sniff around under the carpets to look for leaks.

The drainage channels, am I looking for a hole, or a tube, or what?

Ta so far.
Interior condensation - Xantiargh!
Come to think of it, the rear screen wash has never worked. It makes all the right noises but no water comes out. Is it possible this is leaking into the rear door/boot somewhere? Anyone know the route the pipe takes?
Interior condensation - billy25
this should be easily checked, by filling the resovoir and operating the rear wash/wipe, if the level drops,and it's not going on the screen, then it's going somewhere else,possibly into the cabin area by the route you suggest.

Interior condensation - PhilW
Two thoughts
1. How long are your journeys? Short journeys without car warming up thoroughly will result in lots of condensation from your breath/wet coat/nightime cooling (worst time of year for that 'cos air is still relatively warm with lots of water vapour, yet nights cold so lots of condensation) A good long journey with with heater on might do the trick.
2. Rear washer - had same problem with two Xantias and solved it by
a) Taking off tube at rear wiper and using a piece of thin, plastic coated garden wire down the spigot in wiper spindle (is yours the Xantia with this arrangement?)
b) Detaching tube from roof mounted jet (later Xantias) and affixing foot pump with "lilo" attachment and blowing down tube - cleared it and it worked perfectly
Interior condensation - Andrew-T
Assuming rear wash is fed from the front supply tank, it probably runs above the doors to the back, but may take a lower route. Either way I don't think it will leak into the cabin without you spotting it. Certainly get a hand under the carpets in the door openings to feel for damp.
Interior condensation - Xantiargh!
Ok, had a more in depth hunt...

The sunroof seal (foam bit around the glass) is green and s**den, so i guess that is where my moisture problem probably is.

Maybe it hasn't been closed properly, or has just given up the ghost.

As for the rear wiper. i disconnected the hose from the wiper arm and triggered the washer. No water from the hose. Suppose it must be blocked or severed somewhere between the pump and the boot lid. I'll hae to wait til the weekend and daylight before investigating further.

Thanks for your help guys (and gals?). Is the sunroof likely to be cause, or should I keep looking. Didn't find any damp carpets.
There are leaves under the plastic shield over the front wiper arms. Had an unsuccessful attempt to fish them out with a coat hanger. Not much success, again going to wait for weekend and daylight. Blooming commuting.
Interior condensation - terryb
I reckon you've found it. While you're up around the open sun roof, check the drainage holes and channels are clear. Had the problem on one of my Cits (a Visa I think) and the blockage was right at the bottom (rear of a wheel arch IIRC) where the drain tube discharged. Silly place to put it!

Interior condensation - PhilW
I think I'd be a bit careful before assuming it's the sunroof. When ours leaked it literally flooded the rear footwells - water was swilling around and carpets were soaked to the extent that when it happened in France my explanation to the garage bloke was that we had a swimming pool in the car!. A simple test is to open the sunroof and (gently) pour some water into each corner. Water should drain out behind each front and rear wheel. If it doesn't then one or more drain holes/tubes is blocked or has become detached from the tray - but I am sure you too would have a swimming pool if that was the case!. Note that the sunroof itself is not designed to be waterproof so a bit of gunge on the rubber round the glass is expected -water is supposed to drain into a tray behind headlining then via tubes in the A and C pillars. So I would check suggestions above from RichardW and others first.
I suspect that your rear washer problem is unrelated - try blowing up/sucking (careful!) the tube to clear it. I think that if tube had become detached you would see water emerging somewhere! Sounds like it is just blocked with algae or something.
Interior condensation - PhilW
Try these links also
Interior condensation - Xantiargh!
The foam around the sunroof was green and algae-fied, so I'm assuming that water has been collecting there. I will check the drainage channels at the weekend, however, since squeezing the water out of the foam seal and shutting the sunroof again I have had more normal levels of condensation, i.e. light misting, not running water.

It could just be that the weather is not producing the same amount of condensation as a couple of days ago, but I'm hoping I just hadn't shut the sunroof properly.

I'll update after weekend...

Cheers all
Interior condensation - Andrew-T
Green algae will build up on any horizontal rubber surface, especially if the car lives outdoors. Cars which are only ever superficially cleaned often develop green 'windowsills' within a year or two, so a sunroof seal is an obvious candidate as it may be looked at less often than a window seal. Could well become less efficient at excluding water in that condition.
Interior condensation - terryb
"When ours leaked it literally flooded the rear footwells -
water was swilling around and carpets were soaked to the extent
that when it happened in France my explanation to the garage
bloke was that we had a swimming pool in the car!."

He actually mis-interpreted what you said as "piscine voiture". Close, but no cigar :o)

Interior condensation - Cyd

It doesn't have to be a bad water leak - it only needs to be letting in a dribble to cause the condensation you describe.

Check: sunroof drain channel & drain tubes (if you can, check their condition along their length looking for kinks or splits); around all windows (including bonded glass - there could be a tiny break in the bonding); door seals; bonded in plugs (for paint drainage during manufacture) in the main & boot floor pan; boot seals; heater matrix; around wiper spindles; anywhere where harnessing passes through the body panels (water can track up tightly wound harnesses); the paint seal around door & bonnet & boot hinges; fixings holding in any scuttle trim; roof aerial base; door mirror base; any where else you can think of.

Small water leaks can be VERY VERY VERY DIFFICULT to find (there aren't really enough verys there). We use water with a UV tracer at the oems so we can trace even the smallest leak. Of course, we can take cars completely to bits (in the preproduction phases) to find these leaks - something I dare say you won't want to do!!
Interior condensation - Xantiargh!
What a difference daylight makes...

Pulled up rear seats and had a feel around, the carpets felt dry, but then I noticed condensation on the metal seat base. Pulled the carpet up and low and behold water.

Moved on to testing the sunroof drains. Passenger side rear drain block with mud where it exits in the wheel arch. The water was running down the interior trim and collecting under the passenger side rear seat. Unblocked the drain with a coathanger, hopefully the water will evaporate and problem solved...

Sage advice as always, thanks alot everyone..

Interior condensation - PhilW
Did you find /fix problem with rear washer as well ?
Rear wash/wipe - Xantiargh!
Hi Phil

By disconnecting hoses at various points, I traced the problem to the point at which the water is passed through the boot panel to the wiper via the black bit in the center of the washer nut.

I tried blowing air through the joint but that didn't clear it.

Looking back through this thread I've just noticed the garden wire suggestion. I think that might sort it... again update to follow.

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