Steamy Windows

CiaranMcKeown

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This morning when i got into my car there was a LOT of condensation n the inside of the front windscreen. So heavy infact no amount of hot air blowing on it was going to shift it. It seemed to be concentrated in the centre of the screen so im wondering, does the heating vent in the centre of the dash allow a stream of cold air in during the night? or is there some other reason for this happening and if so...how do i prevent it?

I have a few pics that i will post soon.
 

Brian WH

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This morning when i got into my car there was a LOT of condensation n the inside of the front windscreen. So heavy infact no amount of hot air blowing on it was going to shift it. It seemed to be concentrated in the centre of the screen so im wondering, does the heating vent in the centre of the dash allow a stream of cold air in during the night? or is there some other reason for this happening and if so...how do i prevent it?

I have a few pics that i will post soon.

The two centre vents are certainly fresh/cold air from outside. My immediate reaction anyway to your problem was to suggest that the centre vents were closed at night, before I read your whole post.
 

Mudster

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Maybe the steamy windows are "Oooooo, coming from the body heat"?

I also thought this was a tribute thread to Tina Turner:crazy:
 

television

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The outside air is more dense than that in the car.

Keep the glass clean
Turn the aircon temp down low and demist on
Sit well back from the glass (body heat)
Stop breathing till the glass is clear
 

recycled

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if you park up after using the heater, the hot air in your car will be reduced to its dew point by the cold windscreen and cold air hitting the windscreen,. the temperature of the hot air in your car is reduced to its dew point in effect until it can no longer hold its water and the water gets dumped on the screen and the side glasses.
Same effect if you take a bottle of bear out of the freezer . the cold bottle will reduce the temperature of the air around it and water will be deposited on the bottle as air consits of water vapour as well.the opposite is the steam oozing off your bonnet on a cold/wet day where the heat of the engine boils the surounding water into vapour.

prevent it by covering the screen with tarpaulin preventing contact with cold air or when you park up, put down your windows and let cold air rush in until the temperature inside is the same as outside called thermal equilibrium. or like i do, just keep a hand towel in the car for wiping the screen

Similar to osmosis and diffusion
 
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TheGrocer

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if you park up after using the heater, the hot air in your car will be reduced to its dew point by the cold windscreen and cold air hitting the windscreen,. the temperature of the hot air in your car is reduced to its dew point in effect until it can no longer hold its water and the water gets dumped on the screen and the side glasses.
Same effect if you take a bottle of bear out of the freezer . the cold bottle will reduce the temperature of the air around it and water will be deposited on the bottle as air consits of water vapour as well.the opposite is the steam oozing off your bonnet on a cold/wet day where the heat of the engine boils the surounding water into vapour.

prevent it by covering the screen with tarpaulin preventing contact with cold air or when you park up, put down your windows and let cold air rush in until the temperature inside is the same as outside called thermal equilibrium. or like i do, just keep a hand towel in the car for wiping the screen

Similar to osmosis and diffusion

Is bottled BEAR nice then, and how do you get it into the bottle?i
 

Dieter

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Hi,

'Similar to osmosis and diffusion' Eh....No!

The precipitation of water onto a cold surface is due to condensation i.e. a change in state of water from vapour to liquid (on a cold (temp =< dew point) surface) as was stated but....

Osmosis is the movement of water down it's concentration gradient (through a semi-permeable membrane) and diffusion leads to an equilibrium concentration (of solutes) i.e. neither involves a change in state of water.

Cheers,
 

glojo

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Are you certain you haven't got a leak? Could the carpets have been wet.

If the car's a rockin' then don't come a knockin'

This has also been known to cause 'steamy windows' Allegedly :)

John
 

recycled

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Hi,

'Similar to osmosis and diffusion' Eh....No!

The precipitation of water onto a cold surface is due to condensation i.e. a change in state of water from vapour to liquid (on a cold (temp =< dew point) surface) as was stated but....

Osmosis is the movement of water down it's concentration gradient (through a semi-permeable membrane) and diffusion leads to an equilibrium concentration (of solutes) i.e. neither involves a change in state of water.

Cheers,


thanks. that is why i said similar not the same. the glass being the semi permeable membrane.
diffusion is he movement from higher concentration to lower concentration until the state of equilibriun is reached. it is the opposite of osmosis.
i was just trying to find a real life term hence the word even though it is not exactly like for like.
 
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gl boy

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does misses ciaranMckeown know what you get up to in your car at night?:D ...as already said try the air con on for a few minutes first,got the same problem with my amg if not used for a few day in this cold weather:mad:
 

Sudesh

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Are you certain you haven't got a leak? Could the carpets have been wet.

I was thinking the same! I have an X5 that had this problem,there was a small leak and the water that was comming in was making the windows steam up, once I got that fixed its been fine since!!
 

glojo

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I was thinking the same! I have an X5 that had this problem,there was a small leak and the water that was comming in was making the windows steam up, once I got that fixed its been fine since!!
With my serious hat on..... If the condensation is excessive then this would definitely be my first suspicion.

John
 

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