Fog outside the windows of a double glazing?

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Fog outside the windows of a double glazing?




by the middle » 10/09/11, 10:03

Hello,
Since I have new double glazed windows made in Poland,
I notice that a lot of mornings, I have steam outside my windows.
This is not the case on an old window that is 20 years old.
Is that a good sign, or a bad sign?
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by rpsantina » 10/09/11, 10:44

This means that your outside window is cooler than the outside air ...

: Arrow: so it condenses.

As the gas in the double glazing is free of water vapor, you cannot see anything in the thickness of your tile.

If you don't condense inside, it's because it's well insulated. : Lol:

The cold does not come in, and the heat does not come out.

We would have to find out why this surface becomes colder than the air outside.

Do you have shutters to complete your window insulation?
If yes, try with closed shutter if it changes something.

:?: :?:
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by Christophe » 10/09/11, 11:12

rpsantina wrote:We would have to find out why this surface becomes colder than the air outside.


The inertia of glazing on a cold night which, in the shade, would heat up less quickly than air on a sunny day, right?

In any case, it is a sign of very good insulation! That's good.

ps: Lejuste, I suppose it's on the outside of the outside window? If it's on the inside you have to worry ...
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by dedeleco » 10/09/11, 13:33

This double glazing is screwed up !!
Insufficient quality.
Basic physicist reaction !!
Either it was filled with usual humid air not dry enough at 50 75% humidity !!
Either it leaks because it is not waterproof, and the air in the house enters it (thermal contraction) and does not come out, so that its humidity condenses on the cold wall !!

The only solution to dry this air by circulating it and then sealing it, which is very difficult if the sealing is poorly designed !!!
We put in a moisture absorber, which is quickly saturated if the seal is poor.

As we age, all double glazing will eventually leak and will have this problem !!
Quality determines the number of decades to have this problem.

The insulation is less good because the circulation of water vapor as in a heat pipe transports cold or heat well and it can be worse than a simple window, if not lucky !!!!!


http://fr.wikipedia.org/wiki/Caloduc
A heat pipe comes in the form of a hermetic enclosure which contains a fluid in equilibrium with its gas phase and its liquid phase, in the absence of any other gas.
At one end of the heat pipe, the one near the element to be cooled, le liquid heats up and vaporizes by storing energy from the heat emitted by this element. This gas then diffuses through the heat pipe to the level of a heat sink (or other cooling system) where it will be cooled, until it condenses to become a liquid again, and transfer energy to the ambient air in the form of heat.
The liquid must then return to its starting point, but gravity is not always usable (for example because of the position of the heat pipe), and we prefer to use capillarity

The air slows down the heat pipe which nevertheless remains quite effective, because gravity works well !!
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by Christophe » 10/09/11, 13:35

dedeleco before igniting you should be on what we are talking about: humidity on the inside or outside of the exterior glass.

If it's on the outside like Santina and I think, the glazing is excellent and you got it all wrong! Otherwise, there is a sealing / humidity problem inside the glazing (but I don't think that is it) ...
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by the middle » 10/09/11, 15:42

ps: Lejuste, I suppose it's on the outside of the outside window? If it's on the inside you have to worry.

It's on the garden side, not in the house : Cheesy:
For me too, this is a good sign, but the question is relevant, and allows us to directly recognize a good quality of glazing.
This phenomenon appears between 6 and 9 a.m.
It's new to me ... (new windows, or glazing)
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by dedeleco » 10/09/11, 16:13

The sentence was not precise and clear enough:
It's on the garden side, not in the house

There are 4 surfaces in double glazing !!!
2 internal windows and one outside and one also outside in the house.
So it's not between the windows on the inner side of the outer pane of double glazing, as sometimes on some double glazing with leaks, too old ??? ?
It is on the outside of the outside glass ??,
So just wipe with a cloth and that's okay.
It can be this window which keeps the cold at night and which condenses the humidity outside as long as it is not heated by the sun directly ???
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by Christophe » 10/09/11, 16:31

dedeleco is not trying to catch up with you, you caught fire (again?) too quickly !! He hadn't specified anything at all so there were 2 possibilities ...

lejustemilieu wrote:This phenomenon appears between 6 and 9 a.m.


Correct, this confirms my hypothesis of inertia (cold night = cold glass which heats up less quickly than air and which can therefore pass under the dew point). This is only seen with good quality glazing and provided that it does not heat like a patient (otherwise the exterior glass will be heated by losses despite the good insulation which is never perfect)

We observe the same phenomenon when it is cold and we open a bay window or a window whose outside glass is therefore found inside: it stays cooler than the inside air and quickly fogging appears ...

All wearers of glasses also notice this in winter when entering a heated place. : Idea:

ps: since I put double curtains on double glazing, on a cold night, I have the reverse: fogging inside (which I had not before), which proves that the glazing becomes colder than 'with simple curtains and therefore that double curtains insulate much better than a simple curtain ... (despite the contrary opinion of some ... see little controversy on this subject: https://www.econologie.com/forums/ameliorer- ... t8696.html et https://www.econologie.com/forums/conseil-is ... 10254.html )

I feel that dede will still ignite but it is better to have a little condensation inside (which goes away quickly in the morning) rather than calories which leak all night outside ... : Cheesy:
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by Did67 » 11/09/11, 17:58

Indeed, typical in autumn on quality double glazing or Velux windows.

Ditto to condensation on plants or on the car: these bodies cool more than air by radiation (air mixes), dew point reached, condensation ...

So if it's good on the outer face of the outer glass: it's very good! This window is cold while it is good inside! No "thermal communication" ...
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by Did67 » 11/09/11, 18:04

dedeleco wrote:The sentence was not precise and clear enough:
It's on the garden side, not in the house



The sentence was: "I have steam outside of my glazing "

[everyone can check: it's in the first post, 3rd line]
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