Condensation problem

Rainbowsend

We have an old Fiat motorhome and the long window over the cab there is condensation forming inside the window. This suggests to me that the seal ie the seal that bonds the two panes together has broken down.
A replacement window is the bones of €200 is there anyway we can clear the condensation to avoid replacement. It doesn't bother me but the other half is fussy and would like. It sorted.
I suggested drilling a small hole in the under part to let the condensation dry out then it could be sealed up. Good idea or not?

Maytrix

I repaired a fractured window a month ago with a hair dryer and small gas soldering torch. The window cracked when closing it last year and it gradually fogged up over a number of months. The fracture formed a triangular section in the inner leaf about 6 x 4 x 2 cm which I was able to prize open with a knife just enough to blast in hot air from a hair dryer. It took about 30 minutes to dry it out completely. Then I aligned the segment and placed the flat edge of a paint scraper along one edge of the crack to minimise the extent of the weld area and used the small gas torch to heat along the crack seam just enough to melt both sides together sufficient to seal the crack all along the triangular piece.
It seem to have worked well enough so far. A small amount of condensation has reappeared but it's hardly noticeable.
As you don't have a cracked window it might be more difficult to dry out and unless you can seal the leak it will likely fog up again.