if the inner sides are not stained then they are possible to repair however i know that this is more expensive than fitting new ones
levilewy
June 2010
The inner rails around the edges of the pane contain absorbent silica balls like in those little packets you get in packing to absorb damp.
When they get overloaded your pane mists. A specialist can drill a tiny hole in the outside pane at the bottom to release the damp.
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