I have water damage from consendation on the inside of the windows.

My spouse wants this fixed before I then seal the picture window what had considerable consendation on the outside but the two adjacent windows had none.

So I think there is an air leak that is making out outter pane colder that the others. Maybe everything is sealed but here are the pictures anyway.

The oak seat has some type of finish the pine windows were water based stained and never finished. When wiped with distilled water and the rag turned brown.

Obiously I need to strip the oak assumed to be plywood vener. I tried DNA with no results so no shellac. I tried mineral spirits and lacq thinner and they just seem to clean were the oak has finish.

How best to resolve this issue? I do have one place where oxy acid is requried but do I strip the oak and pine with citric based stripper? I only want to strip the affected areas because a total strip job is too large.

Then some help on how blend then stains so that you do not notice were old and new is.

Thanks all

We have a similar problem on a "garden window" in our dining room. That room also has a small unvented propane fireplace. In the winter, condensation occurs and stained the birch veneer on the floor of the window. I custom fitted a piece of thin birch ply over the original.