Replacing window glass in wooden frames ?

[BARCUD]

Hi all, I know zilch about windows and window frames so maybe you can help me out ?
We moved into our bungalow last year and took the house 'as seen' with obvious jobs needed doing. One job was doing something about the windows.
Basically they are wooden framed, the frames are in not too bad condition, but the double glazing has, I am to understand, 'blown'. There is moisture in between the 2 plates of glass, a right mess !
My wife seems to recall the previous owner saying that they had used the wrong sealer on the windows, hence the mess. Does this sound plausible ? Can using the wrong sealer have caused this condensation/moisture in between the glass ?
I want to replace the glass and I don't want to make the same mistake as the previous owners.
many thanks.

 

[foxhole]

Unlikely , one cause can be failing to put in the spacers under each panel which prevent it sitting in water should rain get under it and allows water to drain out thru drain holes [check these are clear]

 

[God]

But the windows are timber

 

[BARCUD]

Hi and thanks.
So the problem could be the panes are absorbing moisture through the bottom because of a lack of spacers ?
The reference to the wooden frames, are you implying that because they are wooden frames that they wouldn't have spacers ?