much more info needed. is this a new problem? all windows? thermopane or single glass? lots of boiling, cooking location? any changes to heating system or inside reconstruction?
condensation is a dew point problem. warm moist air in contact with a cooler surface (below the dew point temperature ) will cause condensation on the cooler surface. If this is a new situation, either there is to much moisture in the air or there has been a breakdown in the insulation value of the effected surface. for example if a thermopane window seal fails, the insulation value of the glass is reduced and the inside temp on the glass in now lower (below the dew point ) and you have condensation.
Moisture on the windows comes from the glass and/or the frame getting cold enough to be below the dew point of the homes humidity. The location of a return will not matter for this problem. Supply air having enough throw to "wash" the windows with warm air will help. The other fixes would be get better windows or add fresh air to lower the RH of the home.
Far more likly causes would be air leaks around the windows, humidity to high in the home.
Which could be from new constrution, using a non vented gas fireplace, no exhost fan in the bathroom or it's not being run long enough, range hood not venting outside, ECT.
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